Trinidad and Tobago
The Committee, which has prepared this code, include the followings :
Mr. Fenrick De Four National Physical Planning Commission (Chairman)
Mr. Zanim Ali Ministry of Works
Mr. Burnell Austin Ministry of Local Government
Mr. Stephen Basdeo National Emergency Management Authority
Mr. Kenrick Bethelmy Trinidad and Tobago Fire Services
Mr. Mohan Bholasingh Public health inspector - Chairman of Association Mr. Robert Blache-Fraser Trinidad & Tobago Institute of Architects
Mr. Jack Bynoe Board of Architecture of Trinidad & Tobago
Mr. Peter Bynoe Trinidad & Tobago Institute of Architects
Dr. Richard Clarke Board of Engineering of Trinidad & Tobago
Mr. J. Holgar Hackshaw Land Settlements Agency
Mr. Abdul Latiff John Donaldson Technical Institute
Mr. Alan Lodwick Ministry of Housing and Settlements – Town and Country Planning division
Mr. Jameel Mohammed Ministry of Local Government
Mr. Graham Montano Ministry of Works
Dr. Jeffrey M. Phillips Board of Engineering of Trinidad & Tobago
Dr. Jean M. Picchiottino Board of Engineering of Trinidad & Tobago
Mr. Francis Pierre Ministry of Local Government, Sangre Grande Regional Corporation
Mr. Richard Sahadath Ministry of Works
Mr. Madan Singh Public health inspector – Ministry of Health
Mr. Edwin Yuk Low City Engineer, Port of Spain City Corporation
Mr. Errol Rampaul Trinidad & Tobago Bureau of Standards (Secretary 1) Mr. Ishmael A. Soobrattee Trinidad & Tobago Bureau of Standards (Secretary 2) Mr. Aleksandar Brkovic Trinidad & Tobago Bureau of Standards (Secretary 3)
Content
1 SCOPE ... 3
2 NORMATIVE REFERENCES ... 3
3 TERMS AND DEFINITIONS ... 3
4 GENERAL CONSTRUCTION... 3 4.1 PRINCIPLE... 3 4.1.1 Site preparation ... 3 4.1.2 Site clearance... 3 4.1.3 Material storage ... 3 4.1.4 Batter boards ... 3
4.1.5 Driveways and paving... 3
4.1.6 Earth works... 3
4.1.7 Earthquake considerations ... 3
4.1.8 Hurricane considerations ... 3
4.1.9 Roofs... 3
4.1.10 Windows and doors ... 3
4.2 DESIGN CRITERIA... 3 4.2.1 Conventional design... 3 4.2.2 Engineered design ... 3 4.2.3 Dead load... 3 4.2.4 Live load... 3 COASTAL/TIDAL... 3 4.2.5 Roof load... 3
4.2.6 Lateral load design... 3
4.2.7 Load factors ... 3 4.2.8 Deflection ... 3 4.3 MINIMAL REQUIREMENTS... 3 4.3.1 Site address ... 3 4.3.2 Light... 3 4.3.3 Ventilation... 3
4.3.4 Minimum room sizes... 3
4.3.5 Ceiling height... 3
4.3.6 Minimum passage... 3
4.3.7 Sanitation ... 3
4.3.8 Toilet, bath and shower spaces... 3
4.3.9 Glazing ... 3
4.3.10 Enclosed car ports... 3
4.3.11 Emergency escape and rescue openings... 3
4.3.12 Exits ... 3 4.3.13 Landings on stairways... 3 4.3.14 Pedestrian ramps... 3 4.3.15 Stairways... 3 4.3.16 Handrails ... 3 4.3.17 Guards... 3 4.3.18 Smoke detectors ... 3 4.3.19 Foam plastic ... 3
4.3.26 Flood resistant construction ... 3
4.3.27 Coastal high hazard areas... 3
4.4 BASIC MATERIALS... 3
4.4.1 Reinforced Concrete... 3
4.4.2 Timber ... 3
4.4.3 Metal... 3
4.5 ALTERNATE MATERIALS AND TYPES OF CONSTRUCTION... 3
4.5.1 General... 3
4.5.2 Standards ... 3
5 FOUNDATIONS ... 3
5.1 GENERAL... 3
5.1.1 Load bearing walls and columns... 3
5.1.2 Reinforcement ... 3
6 VERTICAL STRUCTURES... 3
6.1 CONCRETE AND MASONRY... 3
6.1.1 Masonry block walls ... 3
6.1.2 Columns, beams and shear panel structure... 3
6.1.3 Framed structure ... 3
6.2 TIMBER... 3
6.2.1 Identification and grade... 3
6.2.2 Exterior walls... 3
6.2.3 Interior load bearing walls ... 3
6.2.4 Interior non-bearing walls... 3
6.2.5 Drilling and notching-studs ... 3
6.2.6 Headers ... 3 6.2.7 Cripple walls... 3 6.2.8 Wall bracing... 3 6.2.9 Structure... 3 6.2.10 Cladding... 3 6.3 METAL... 3
6.3.1 MS beams and profiles ... 3
6.4 MIXED CONSTRUCTION... 3
7 FLOOR SYSTEMS... 3
7.1 CONCRETE FLOOR SLABS... 3
7.1.1 Layout... 3
7.1.2 Finishing ... 3
7.1.3 Services... 3
7.2 TIMBER... 3
7.2.1 Identification & Grade... 3
7.2.2 General... 3 7.2.3 Floor sheathing... 3 7.3 METAL... 3 7.3.1 MS steel beam ... 3 8 ROOF ASSEMBLIES ... 3 8.1 ROOF STRUCTURE... 3
8.1.1 Concrete roof structure ... 3
8.1.2 Timber ... 3
8.1.3 Metal... 3
8.2 ROOF COVERING... 3
8.2.1 Weather protection ... 3
8.2.2 Materials ... 3
8.2.3 Requirements for material roof covering... 3
ANNEX « A » ... 3
A.1.2 Form of application to build ... 3
A.1.3 Approval in part ... 3
A.2 APPROVALS... 3
A.3 INSPECTIONS... 3
A.3.1 Procedure ... 3
A.4 COMPLETION CERTIFICATE... 3
A.5 COMPLIANCE... 3
A.6 ALTERNATE MATERIALS AND TYPES OF CONSTRUCTION... 3
A.6.1 Application... 3
Note:
FOREWORD
The Trinidad & Tobago Small building Code was declared a National Standard on ---, 2004 After the draft finalized by the Small Building Committee had been approved by the Trinidad & Tobago Bureau of Standards.
The preparation of this code/standard arose out of the need to improve the quality of Trinidad and Tobago’s house while assuring that the safety of the structure is maintained.
In the preparation of this code, extensive use has been made of the Parts of the Caribbean Uniform Building Code (CUBIC) which deals with small buildings. The CUBIC is at this time being considered for revision and the management Committee for the revision project has elected to make use of the International Code Council Inc., of the U.S.A. in the provision of base documentation for the revision of CUBIC. In like manner for this code use has been made of the I.B.C. year 2000. International Residential Code Final Draft 1998.
The small Building Code is a document which has been put together by several public and private organisations in Trinidad and Tobago to streamline the approval and construction of small, non complex building structures and ensure that work is completed in a manner that conforms to acceptable standards.
The drafting of the code document has been managed by the Board of Engineering of Trinidad & Tobago, sponsored by the Joint Consultative Council in the Construction Industry and the Interim National Physical Planning Commission with the support and active participation of the Trinidad & Tobago Bureau of Standards.
The first edition of this code provides simple guidelines for the construction of small buildings (residential, office or light industrial) where use is made of concrete foundations, masonry block walls or timber and metal frame or wooden roofing system.
Future editions of this code will cover all types of small buildings constructed with concrete, masonry block walls, steels and timber, metal or any combination of these
Future editions of this code will cover also openings, floor, ceiling and wall finishing , burglar-proofing to make with the plumbing and the electrical codes of Trinidad and Tobago a complete collection to cover the Small Buildings.
1 Scope
1.1 These provisions shall be known as the “Trinidad and Tobago Small Building Code” and shell refer to
herein as “This Code”.
1.2 The provisions in this code shall apply to the construction, alteration, movement, enlargement, repair,
equipment, use occupancy, location, maintenance, removal and demolition of buildings, for single or multiple family residential or general purpose use of not more than two stories in height and with a gross floor area of three hundred square metres (300m2) or less.
1.3 This code is intended to provide minimum requirements to safeguard life, limb, health and public
welfare. It calls for minimum requirements for building materials in common use and takes into consideration the need for protection against wind and earthquake.
1.4 Sufficient detail is provided to allow for the adequate preparation of plans for buildings under normal
environmental conditions. Regulatory authorities would deal with approvals on the basis of adherence to the requirements of this code. (see Annex A – Administration and Enforcement)
1.5 The builder/designer is advised to seek assistance from registered professionals in the design and
construction of wind and earthquake resistant structures for buildings outside the scope of this code and/or for special application or other than normal environmental conditions.
2 Normative references
This chapter lists the standards that are referenced in various sections of this document.
ASTM
American Society for Testing and Materials 100 Barr Harbor Drive
West Conshohocken, PA 19428
Standard reference
number Title Code reference
ASTM A 755M - 94 Specification for steel sheet, metallic coated by the hot dip process and pre-painted by the coil-coating process for exterior exposed building products
Roof materials
ASTM B 101-96 Lead coated copper sheets Roof materials
ASTM C 34-96 Specification for structural clay
load-bearing wall tile. Hollow masonry blocks
ASTM C 406 - 89 Specification for roofing slate Roof materials ASTM C 652-95a Specification for hollow brick (Hollow
masonry units made from clay or shale)
Hollow masonry blocks
ASTM C 1167 - 94a Specification for clay roof tiles Roof materials ASTM D 224 - 89 Specification for smooth surfaced asphalt
roll roofing (Organic felt)
Roof materials
ASTM D 225-95 Asphalt shingles (Organic felt) surfaced
with mineral granules Roof materials
ASTM D 226-94 Specification for asphalt-saturated organic
felt used in roofing and water proofing Roof materials ASTM D 227-97a Coal tar saturated organic felt used in
roofing and waterproofing Roof materials
ASTM D 249-89 (96) Specification for coal tar saturated organic
felt used in roofing and water proofing Roof materials ASTM D 312-84 Specification for asphalt used in roofing Roof materials ASTM D 450-96 Coal tar pitch used in roofing,
ASTM D 1863-93 (96) Mineral aggregate used in built up roofs Roof materials ASTM D 2178-97a Asphalt glass felt used in roofing and
waterproofing Roof materials
ASTM D 2626-97a Asphalt saturated and coated organic felt
base sheet used in roofing Roof materials
ASTM D 3462-97a Asphalt shingles made from glass felt and
surfaced with mineral granules Roof materials
ASTM D 3909-97a Asphalt roll roofing (Glass felt) surfaced
with mineral granules Roof materials
ASTM D 4601-97a Asphalt coated glass fibre base sheet used in roofing
Roof materials
ASTM D 4869-88 Asphalt saturated organic felt underlay used in roofing
Roof materials
ASTM D 4897-97a Asphalt coated glass fibre venting base
sheet used in roofing Roof materials
ASTM D 4990-97a Coal tar glass felt used in roofing and
waterproofing Roof materials
ASTM E 84-91a Test method for surface burning
characteristics for building materials Foam plastic
Flame spread and smoke density
Insulation ASTM E 90-90 Test method for laboratory measurement
of airborne sound transmission loss of building partitions
Dwelling unit separation
ASTM E 96-92 Standard test methods for water vapour transmission of materials
Moisture vapour barriers
ASTM E 119-88 Test methods for fire tests of building
construction and materials Dwelling unit separation
ASTM E 492-90 (96) Test method for laboratory measurement of impact sound transmission through floor ceiling assemblies using the tapping machine
Dwelling unit separation
ASTM E 814-94b Test method for fire tests of through
penetration fire stops Dwelling unit separation
ASTM E 970-94a Standard test method for critical radiant
AWPA
American Wood-Preservers Association PO Box 5690
Granbury, Texas 76049
Standard reference
number Title Code reference
C1-90 All timber products- Preservative
treatment by pressure processes Protection against termites
C15-90 Wood for commercial-residential
construction- Preservative treatment by pressure processes
BS
British Standards
Standard reference
number Title Code reference
BS EN 490 : 1994 Concrete roofing tiles and fittings.
Product specifications. Roof materials
CPSC
Consumer Product Safety Commission 4330 East West Highway
Bethesda, MD 20814-4408
Standard reference
number Title Code reference
CPSC 16-CFR, part
1201-77 glazing Safety standard for architectural Glazing CPSC 16-CFR part
1209-79 cellulose insulation Interim safety standard for Insulation CPSC 16-CFR part
CUBIC
Standard reference number
Title Code reference
IRC
International Residential Code for One and Two Family Dwellings Doubletree Hotel
3050 Bristol Street Costa Mesa, CA 92626
Standard reference
number Title Code reference
ISO
Case postale 56 CH- 1211 Geneva, 20 Switzerland
Standard reference
number Title Code reference
STD Version 1 STD template for the preparation of normative-type documents.
Reference manual.
Presentation of the "Small building code".
TTS
Trinidad and Tobago Bureau of Standards Trincity Industrial Estate
TTS 16 80 400: 1991 Code of practice for the design and construction of septic tanks and associated secondary treatment and disposal system.
Sanitation
TTS 16 35 508 Specification for load bearing
masonry concrete units. Hollow masonry blocks
TTS 16 35 509 Specification for non load bearing
concrete masonry units. Hollow masonry blocks
TTS 587:2003 Hollow clay block –vertical core TTS 588:2003 Hollow clay block –horizontal core TTS 16 35 511: 1998 Specification for corrugated
galvanised and aluzinc coated steel sheets for roofing and general purpose.
Roof materials
TTS 171 Electrical code Dwelling unit separation
TTS 583:2000 Carbon steel bars for the
reinforcement of concrete - Specification
Basic materials
ULC
Underwriters Laboratories of Canada 7 Crouse Road
Scarborough, Ontario, Canada MIR 3A9
Standard
reference number Title Code reference
S102.2 - M88 Standard method of test for surface burning characteristics of flooring, floor covering and miscellaneous materials and assembly
3 Terms and definitions
3.1 Addition
An extension or increase in floor area or height of the building or structure.
3.2 Anchor
Metal rod, wire, or strap that secures masonry or any structure to its structural support.
3.3 Approved
Acceptable to the building official
3.4 Attic
The space between the ceiling beams of the top story and the roof rafters.
3.5 Balcony
An exterior floor projecting from and supported by a structure without additional independent supports.
3.6 Basement
That portion of a building, which is partly or completely below grade.
3.7 Building
Any structure used or intended for supporting or sheltering any use or occupancy
3.8 Cement plaster
A mixture of Portland or blended cement, and hydrated lime, masonry cement or plastic cement and aggregate and other approved materials as specified in the code.
3.9 Cladding
The exterior surface of the building envelope that is directly loaded by the wind.
3.10 Column
A member with a ratio of height to least lateral dimension exceeding 3, used primarily to support axial compressive load.
3.12 Construction documents
Written, graphic and pictorial documents prepared or assembled for describing the design, location and physical characteristics of the elements of the project necessary for obtaining a building permit. Construction drawings shall be drawn to an appropriate scale.
3.13 Dead loads
Consist of the weight of materials of construction incorporated into building, including but not limited to walls, floors, ceilings, stairways, built in partitions, finishes, cladding and other similarly incorporated architectural and structural items, and fixed service equipment, including the weight of cranes.
3.14 Diaphragm
A horizontal or nearly horizontal system acting to transmit lateral forces to the vertical resisting elements. When the term “diaphragm “ is used, it includes horizontal bracing systems.
3.15 Dwelling
A building, which contains one or two dwelling units used, intended or designed to be built, used, rented, leased, let or hired out to be occupied, or which are occupied for living purposes.
3.16 Dwelling unit
A single unit providing complete independent living facilities for one or more persons including permanent provisions for living, sleeping, eating, cooking and sanitation.
3.17 Emergency escape and rescue opening
An openable window, door, or other similar device that provides for a means of escape and access for rescue of and emergency.
3.18 Fibreboard
A fibrous, homogeneous panel made from lignocelluloses fibres (usually wood or cane) and having a density of less than 500kg/m3 and more than 160kg/m3.
3.19 Fire resistance
That property of material or their assemblies that prevents or retards the passage of excessive heat, hot gases or flames under conditions of use.
3.20 Fire resistance rating
The period of time a building or building component maintains the ability to confine a fire or continues to perform a given structural function or both.
3.21 Floor area (gross and net) a) Gross
The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridor, stairways, closets, the thickness of the interior
b) Net
The actual occupied area not including unoccupied accessory areas such as corridors, stairways and closets.
3.22 Guard
A building component or a system of building components located at or near the open sides of elevated walking surfaces that minimise the possibility of a fall from the walking surface to a lower level.
3.23 Gypsum board
Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, pre-decorated gypsum board, or water- resistant gypsum baking board.
3.24 Habitable space
A space in a building for living, sleeping, eating or cooking. Bathrooms, toilet rooms, closets, hall, storage or utility spaces and similar areas are not considered habitable spaces.
3.25 Handrail
A horizontal or sloping rail intended for grasping by the hand for guidance or support.
3.26 Header
A masonry unit that connect two or more adjacent withes of masonry.
3.27 Interior finish
Interior finish includes interior wall and ceiling finish and floor finish.
3.28 Interior floor finish
The exposed floor surfaces of buildings including coverings applied over a finished floor or stair, including risers.
3.29 Interlayment
A layer of felt or non-bituminous saturated felt not less than 450mm wide, shingled between each course of a wood shake roof covering.
3.30 Joint
The linear opening in or between adjacent fire resistance rated assemblies that is designed to allow independent movement of the building, in any plane, caused by thermal, seismic, wind or any other loading.
3.32 Load factor
A factor that accounts for deviations of the actual load from the nominal load, for uncertainties in the analysis that transforms the load into a load effect, and for the probability that more than one extreme load will occur simultaneously.
3.33 Lot
A portion or parcel of land considered as a unit.
3.34 Masonry
A built up construction of building units or materials of clay, shale, concrete, glass, gypsum, stone, or other approved units bonded together with or without mortar or grout or other accepted method of joining.
3.35 Garage
Enclosed carport.
3.36 Mortar
A plastic mixture of approved cementations materials, fine aggregate and water used to bond masonry or other structural units.
3.37 Owner
Any person, agent, firm or corporation having a legal or equitable interest in the property.
3.38 Panel (part of the structure)
The section of a floor, wall, or roof comprised between the supporting frame of two adjacent rows of columns and girder or column bands of floor or roof construction.
3.39 Permit
An official document or certificate issued by the authority having jurisdiction that authorizes performance of a specified activity.
3.40 Pile foundations
Pile foundations consist of concrete or steel structural elements either driven into the ground or cast in place. Piles are relatively slender in comparison to their length, with lengths exceeding 12 times the least horizontal dimension. Piles derive their load carrying capacity through skin friction, through end bearing or a combination of both.
3.41 Pier foundations
Pier foundations consist of isolated masonry or cast in place concrete structural elements extending into firm materials. Piers are relatively short in comparison to their width, with lengths less than or equal to 12 times the least horizontal dimension of the pier. Piers derive their load-carrying capacity through skin friction, through end bearing or a combination of both.
3.42 Plain concrete
Structural concrete with no reinforcement or with less reinforcement than the minimum amount specified for reinforced concrete.
3.43 Plain masonry
Masonry in which the tensile resistance of the masonry is taken into consideration and the effect of stresses in reinforcement are neglected.
3.44 Plywood
A wood structural panel comprised of plies of wood veneer arranged in cross-aligned layers. The plies are bonded with an adhesive that cures on application of heat and pressure.
3.45 Preservative (treated wood)
Wood including plywood impregnated under pressure with compounds, which reduce their susceptibility to flame, spread to deterioration caused by fungi, insects, or marine borers.
3.46 Ramp
A walking surface that has a running slope steeper than 5%.
3.47 Registered professional
An individual who is registered or licensed to practice their respective profession as defined by the statutory requirement of the professional registration laws of the country in which the project is to be constructed.
3.48 Reinforced concrete
Structural concrete reinforced with no less than the minimum amounts of pre-stressing tendons non-pre-stressed reinforcement.
3.49 Roof assembly
A system designed to provide weather protection and resistance to design loads.
3.50 Roof covering
The covering applied to the roof deck for weather resistance, fire classification or appearance.
3.51 Roof covering system
The system consists of a roof covering and roof deck or a single component serving as both the roof covering and the roof deck.
b) Wood
A wall designed to resist lateral forces parallel to the plane of the wall.
3.53 Stair
A change in elevation, consisting in one or more risers.
3.54 Stairway
One or more flights of stairs, either exterior or interior, with the necessary landings and platforms connecting them, to form a continuous and uninterrupted passage from one level to another.
3.55 Stirrup
Reinforcement used to resist shear and torsion stresses in a structural member; typically bars, wires or welded wire fabric either single leg or bent into L, U or rectangular shapes and located perpendicular to or at an angle to longitudinal reinforcement.
3.56 Story
That portion of the building included between the upper surface of the floor and the upper surface of the floor or roof next above.
3.57 Structure
That which is built or constructed.
3.58 Tile
A ceramic surface unit, relatively thin in relation to facial area, made from clay or a mixture of clay or other ceramic materials.
3.59 Treated wood
Wood impregnated under pressure with compounds, which reduce their susceptibility to flame, spread or to deterioration caused by fungi, insects or marine borers.
3.60 Underlayment
One or more layers of felt, sheathing paper, non-bituminous saturated felt, or other approved materials over which a steep-slope roof covering is applied
3.61 Vapour barrier
A material having a good permeance rating such as foil, plastic sheeting, or insulation facing installed to resist the transmission of water vapour through the exterior envelope.
3.62 Ventilation
The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from any space.
3.63 Wall (load bearing)
a) Any metal or wood stud that supports more than 1.50 kN/m of vertical load in addition to its own weight.
b) Any masonry or concrete wall that supports more than 3 kN/m of vertical load in addition to its own weight.
3.64 Wall (non load bearing)
4 General construction
4.1 Principle
4.1.1 Site preparation
4.1.1.1 Preliminary investigation
Before any construction work commences, it shall be determined whether planning permission and other approvals would be required from the competent (relevant) authorities. A preliminary inspection of the site shall be undertaken so that preparation may be made for any problems or difficulties that may arise. This time should also be used to plan how the site will be organised so that a logical layout may emerge.
4.1.1.2 Checklist for site conditions
Completion of the checklist below will provide enough information about the site and its conditions to permit construction to begin.
4.1.1.2.1 Forms and documents
a) Has planning permission been obtained?
b) Is there a surveyor's or topographical drawing of the site?
4.1.1.2.2 Site
c) The shape and sizes of plot conform to those shown on the layout plan d) Is easy access to the site available?
e) The site can be adequately drained?
f) Have the location of all boundary markers been found?
g) Are water, sewage disposal facilities and an electricity supply available on site?
h) Take note of the general topography of site and other physical conditions likely to cause hazards. i) Is there evidence of termite infestation in the soil or trees?
j) Will there be a need for the removal of large trees? k) Is the area normally subject to land slippage?
l) Is there adequate natural provision for the removal of storm water i.e. drainage of water as a result of heavy rains or flooding.
m) Will construction endanger any of the public utility services? n) Determine the height of the water table if appropriate.
o) Determine whether the soil is suitable for the construction of a soak-away pit. p) Determine the ground floor datum.
q) Determine the depth of the foundation stratum, if feasible. r) Select suitable areas for stockpiling aggregate.
s) Select an area for the location of a concrete mixer or for the hand-mixing of concrete. t) Select location of a materials storage shed.
u) Are there existing structures to be removed or altered?
Completion of the above checklist should highlight possible construction problems as well as the requirements of plant and materials. Where foundation problems are evident it is recommended that an engineer or any other appropriate professional be consulted.
4.1.2 Site clearance
4.1.2.1 Care should be taken to preserve any trees on the site. Where it is necessary to remove any
trees, special care shall be taken to remove, totally, all roots and stumps of the felled trees as well as any of the other remains from the site.
Note: There may be statutory limitations on the extent to which large trees may be removed. Consult with the Ministry of Agriculture for further clarification.
4.1.2.2 The area where the building will be situated shall be stripped of topsoil. This material should be
stock piled in a suitable area for later use during landscaping.
4.1.3 Material storage
4.1.3.1 Areas shall be allocated on the cleared site for the storage of materials. Coarse and fine
aggregate for the mixing of concrete and mortar shall be placed in separate heaps in a location near to the concrete mixer or concrete mixing area.
4.1.3.2 Cement, nails and finished materials (groove ply, PVC pipe, galvanised sheeting etc.) requiring
protected storage shall be stored in a shed, which is weather tight and has a wooden floor raised not less than four inches off the ground.
4.1.3.3 Reinforcement steel shall be stacked off the ground to reduce corrosion.
4.1.4 Batter boards
The building shall be properly set out on the site according to the building plan. Batter boards, which are horizontal boards parallel to the sides of the building and supported by vertical boards driven into the ground shall be erected in convenient locations near the four (or more) corners of the building, and to these boards should be transferred the building lines and levels for the project.
4.1.4.1 The floor level is usually marked on the batter boards and used as a permanent reference. All
wall lines and levels shall be referred to these boards. Periodic checks shall be made to ensure that these boards have not been shifted from their intended positions.
4.1.5 Driveways and paving
4.1.5.1 The driveways and paving dealt with in this section are those suitable for use as driveways and
parking areas for private cars and light goods vehicles only. Driveways shall be not less than 3m wide.
4.1.5.2 The choice of flexible (asphalt) or rigid (concrete) paving is largely influenced by the soil
conditions at the site and the cost of driveway. Gravel driveways and paving are acceptable if adequate drainage is available and if the gravel or crushed rock is reasonably hard, free from clay, and would not be easily crushed by the light traffic. Adequate provision for drainage shall be made.
4.1.5.3 Where firm soils or rocks are present, any type of paving previously mentioned may be used.
Where soft soils are present gravel or a flexible paving is recommended.
4.1.5.4 For all kinds of paving the topsoil shall be removed and replaced by a minimum of 150 mm of
compacted, granular material.
4.1.5.5 For rigid paving, a concrete slab with a minimum thickness of 100 mm is required, reinforced by
welded wire mesh of minimum 100 mm2/m wide in both directions, placed 25 mm below the top surface of the slab. Construction joints shall be created every 5 m.
Note: A98, A142 and 150x150X4.5 BRC are acceptable.
4.1.5.6 For flexible paving a minimum thickness of 50 mm of asphalt (cold or hot mix) shall be applied
and compacted by roller on an approved and adequate sub base.
4.1.6 Earth works 4.1.6.1 Site topography
4.1.6.1.1 The natural topography of the land should be maintained and any excavation or back filling
that must be carried out (and deemed as necessary) should be kept to a minimum. This is necessary to maintain the natural vegetation, prevent landslides and flooding and preserve in general the natural environment.
4.1.6.1.2 It is essential therefore those buildings should be constructed in such a manner to compliment
the natural topography of the site and not vice-versa.
4.1.6.2 Soil conditions
4.1.6.2.1 The characteristics of the site soil conditions shall be ascertained. If necessary, compaction
shall be carried out in order to improve the bearing value of the soil.
4.1.6.2.2 Where expansive clay is encountered or where problem conditions are present, professional
4.1.6.3 Excavations
4.1.6.3.1 Excavations for foundations shall be carried out along the building lines to the depth of the
foundation stratum identified as suitable.
4.1.6.3.2 Excavations not exceeding 1.2 m in depth may generally be without planking and strutting,
which is a system of braced timber walls erected against the faces of the excavation to prevent collapse. For excavations exceeding 1.2 m the extent of planking and strutting necessary shall be determined by the nature of the soil and the location of the water table.
4.1.6.3.3 Where collapse of the side of excavation is anticipated, all excavation in excess of 1.2 m in
depth shall be planked and strutted.
4.1.6.3.4 Where the foundation is in rock, it shall be excavated at least 50 mm to provide a key for the
foundations.
4.1.6.3.5 The bottom of all excavations shall be level and firm. Where loose materials are encountered,
foundation bottoms shall be compacted by ramming.
4.1.6.3.6 Where excavations have been carried beyond their generally required depth, either by
accident or design, the deep areas shall be back filled with compacted, adequate material or with Grade E concrete (see Table 6).
4.1.6.4 Back filling
4.1.6.4.1 Back filling shall not be carried out in dry rivers, natural drains, where water flows after heavy
rains and along thalwegs (lowest areas in valleys).
4.1.6.4.2 Back filling around foundation walls and under floor slabs shall be carried out using only
suitable, selected materials. Unless the floor slab is reinforced to act as a suspended slab, the depth of fill shall not exceed 1m.
4.1.6.4.3 Suitable fill material may be brought to the site or obtained from excavated material, provided
always that such material is free of substantial amounts of clay or organic matter.
4.1.6.4.4 All backfill shall be well compacted in layers not exceeding 150 mm in thickness where
compaction is by manual methods. Where mechanical compaction equipment is used, the thickness of layers may be increased to 225 mm.
4.1.6.4.5 Where back filling under floor slabs on grade has been effected using hard core, a 50 mm
layer of sand shall be applied to the top of the compacted hard core to protect damp proof membranes from puncture.
4.1.7 Earthquake considerations
4.1.7.1 Earthquake resistant construction
4.1.7.1.1 General
Trinidad and Tobago is in an earthquake zone and has experienced varying degrees of damage due to earthquakes. It is therefore essential that buildings are designed and constructed so that they have some resistance to the shaking or lateral forces produced by earthquakes.
4.1.7.1.2 Effect of soil type
a) The type of soil at the site may have a significant effect upon the resistance of the building to an earthquake. However for buildings within the scope of this code the effect of the soil type is not so significant provided that the building is not constructed on loose saturated sands, which may liquefy during an earthquake and cause collapse of the building.
b) The earthquake may also, due to shaking of the ground, compact loose sand or fill material, and if
a building is constructed on such material, the building will be damaged.
4.1.7.1.3 Effect of high seas
Buildings on coastal areas may suffer due to high waves produced by earthquakes, and therefore the sitting of the building in relation to the sea level needs to be considered. Professional advice shall therefore be sought in such cases.
4.1.7.1.4 Building shape
a) The success with which a building survives an earthquake is greatly affected by its shape in plan,
the way the building is tied together and the quality of construction.
b) Most buildings with a simple rectangular shape with no projections (or only short projections) perform well under earthquake conditions provided the construction is adequate.
c) Long narrow buildings should be avoided by limiting the length to three times the width. If the
building must be longer, then it should be divided into separate blocks with adequate separation. Figure 1 illustrates desirable and undesirable plan shapes.
d) Rectangular buildings with well inter-connected cross walls are inherently strong and therefore
Fig 1 - Plan of building proportion
Separation of Blgs
to improve resistance
Long undesirable plans
Fig 2 - Recommended location of wall openings
2 0 20 1 10 0 Floor level Floor level 1 0 00 400 4001 800mm min Shear panel
Not acceptable opening location
Too narow Too narow
Not enought shear panel
Ground level
First floor
60 0 m m m in im umFirst floor
Ground level
6 0 0 m m m in im um4.1.7.1.5 Appendages
Where buildings have decorative or functional additions or appendages such as window hoods, parapets and wall panels etc. extreme care must be taken to ensure that they are securely fixed, since many of such items tend to fall easily and may cause damage during an earthquake.
4.1.7.2 Rules for the construction of earthquake resistant buildings
It is recommended that the following rules be followed for the construction of buildings:
4.1.7.2.1 Masonry buildings
An important factor contributing to the earthquake resistance of masonry buildings is the detailing and placing of steel reinforcement. A registered professional should undertake the design of a reinforced concrete frame building. The reinforcing guide given in this section therefore must only be used for simple single storey buildings constructed of approved quality masonry blocks. For the minimum quantities of reinforcing steel to be used refer to SECTION 5 Vertical Structures.
4.1.7.2.2 Timber buildings
There are two additional areas of concern with respect to timber buildings: --- All corners and intersections must be adequately braced.
--- Earthquake and hurricane forces tend to remove timber buildings from their supports by shaking. Because of this, sills shall be securely fastened to foundations.
4.1.7.2.3 Steel buildings
The natural ductility of steel protects the frame from severe damage. However, in many cases masonry block walls are used and the precautions already listed for these walls will apply. The wall reinforcement must now be anchored by welding to the steel columns and beams, or the steel frame encased in concrete in which case the wall reinforcement can be tied into the concrete cage encasing the steel frame.
4.1.7.3 Location of openings
4.1.7.3.1 The location and size of openings in walls have a significant effect upon the strength of a wall
and its ability to resist earthquake forces.
4.1.7.3.2 Openings shall be located away from a corner by a clear distance of at least 1/4 of the height
of the opening. It is recommended that the minimum distance be 400 mm.
4.1.7.3.3 The total length of the openings should not exceed 1/2 the length of the wall between
con-secutive cross walls (see Figure 2).
4.1.7.3.4 The horizontal distance between two openings should not be less than 1/2 the height of the
shorter opening (see Figure 2).
4.1.7.3.5 For two storey buildings, the vertical distance from an opening to one directly above it shall
4.1.8 Hurricane considerations
4.1.8.1 Hurricane resistant construction 4.1.8.1.1 General
a) It is very important in Trinidad and Tobago to be ever conscious of the fact that the region lies in the hurricane belt. Because of this, hurricane resistant construction principles must be adhered to if safe buildings are to be erected. This section gives general principles for safe hurricane resistant design, and it is recommended that the details shown in these guidelines must be adhered in order to ensure safe construction.
b) For the buildings within the scope of this document the areas most vulnerable to hurricane forces
are the roofs, windows, walls and appendages.
c) The underlying objective of hurricane resistant construction is to produce a building that will not
collapse during a hurricane. The building must be standing and its occupants should be safe.
4.1.8.2 Rules for the construction of hurricane resistant buildings
4.1.8.2.1 Building site
a) Buildings sited in exposed areas (e.g. on the brow of a hill or near coastal areas) are most vulnerable, while those sheltered by natural topography are less vulnerable. Buildings sited in gullies or riverbeds are very vulnerable as they are subject to severe damage by floods caused by the heavy rains, which often accompany a hurricane.
b) In sitting the building, therefore, steep slopes and edge of cliffs should be avoided, as well as
other conditions such as steep sided valleys where exceptionally high wind speeds are found.
c) Tie beams should be constructed to reduce the untied height of the columns to a maximum of 3
meters as shown in Figure 5. It is advisable to seek professional assistance for such construction, unless otherwise designed for larger columns.
4.1.8.2.2 Timber buildings
a) Because of the relatively light nature of a timber building, extra precautions shall be taken to
prevent uplift. Care must therefore be taken to ensure that the entire structure is securely fastened to the foundations.
b) The spaces between the supporting columns or piers may be filled in to reduce the uplift forces
(see Figure 6).
c) As far as timber walls are concerned, in addition to bracing corners in both directions, diagonal
braces or steel straps must be installed at the level of the top plate to provide rigidity of the corners at that level (see Figures 7 and 8).
Fig 4 - Typical roof gable wall arrangement
frame of building concrete ring beam roof reinforced floor level roof level width of wall 50 m m min
Roof level
Reinforced concrete ring beam
Frame of building Floor level 200mm thk. r.c. blockwall r.c. strip footing 200x300 r.c. tie beam
Ground slopes should be less than 15 degrees
Existing grade 6 0 0 m m m in 9 0 0 m m m in
Steep slopes more than 15 degrees 300x300 mm min r.c. column r.c. footing frame of building 200x300 r.c. tie beam existing grade r.c. footing 3 0 0 0m m m a xi m um
and less than 30 degrees
Note: Those sketches don't show the shear panels
Reinforced concrete ring beam
Roof level
100 X 100 Timber sill
r.c. tie beam
150 mm thick blockwork
Grade
Colomn may be 200 x 200mm reinforced concrete or block work filled with concrete and 4 - 12mm bars 8mm links - 200mm centers
Horizontal bracing for corners at wall plate level
Wall plate
Uprights
Sheating
Wall sill Brace corners by diagonal bracings
Fig 7 - Timber framing showing bracing
Wall sill
Door opening
Window opening
Wall sill is fixed to foundation wall by anchor bolts
Wall plate must be fastened and strapped to the top of uprights
The uprights are fixed to Double uprights
Fig 9 - Rafter/wall plate connections
Fig 10 - Rafter/ ring beam connections
roof sheetingroof battens
ceiling material
fascia board metal hurricane tie
every other rafter
timber wall plate
r.c. ring beam 150 20 0 50 x 150 timber rafter at 600mm centers
roof eave 900mm (max)
50 x 100 timber wall plate
12mm anchor bolt at 1200mm centers (maximum) r.c. ring beam
10
0m
m
m
in
T 6mm stirrups @ 200 ctsTimber rafter
Infill concrete
r.c. ring beam
metal hurricane tie imbedded in ring beam
metal hurricane tie Timber wall plate
Timber wall plate
Metal strap
Timber upright
Timber wall plate
Timber upright Mortise
4.1.8.2.3 Steel buildings
The principles for the design and construction of hurricane resistant steel buildings are:
a) Ensure that there are adequate numbers and sizes of foundation holding down bolts, and that they are all in place and properly fixed.
b) Ensure that there is adequate lateral support provided by cross bracing or horizontal ties or by cast in place concrete or masonry walls.
c) Where concrete walls or concrete masonry is used, the connections between the steel frames and the walls shall be provided.
d) Ensure that the fabricator's recommendations with regards to the construction of the roof and roof covering are followed.
4.1.9 Roofs
4.1.9.1 Roofs with pitch between 0 and 20° (or a slope between 0 % and 36 %) are more vulnerable to
uplift forces. It is recommended that roofs be constructed with a pitch between 20° and 40° (or a slope between 36 % and 84 %).
4.1.9.2 The aptitude to reduce uplift forces is affected by the shape of the roof in the following order from the most effective to the least effective:
a) Hip roof b) Gable c) Shed
4.1.9.3 Attention should be given to the location of fixings used for the roof cladding. It is necessary to provide additional fixings at the roof edges and ridge, since high-localised pressures are produced in these locations.
4.1.9.4 Roof overhangs also experience high local pressures and, where possible, these should be kept
to a minimum or adequately strengthened.
4.1.9.5 Where buildings have covered patios or verandas, their roofs may be separate structures rather
than extensions of the main building roof. A patio or veranda roof may be lost without endangering the safety of the main roof.
4.1.9.6 The main roof must be securely fixed to the ring beam and ridge beams and details for achieving
this are shown in Figures 9, and 10 and 11.
4.1.10 Windows and doors
Special attention must be paid to the installation of doors and windows, since the loss of a door or window during a hurricane will greatly alter the internal pressure of the building, thus adversely affecting its safety. For this reason, glazed windows and doors may be fitted with shutters.
G ro und flo o r sl ab s u sp e nd ed S h e ar p a ne l M as o n ry S u sp e nd e d g ro u nd fl o o r sl ab w ith c ra w l s pac e G ro un d flo o r sl ab s us pe n de d o r on g ra de Sus pe n d ed fi rs t flo or s la b M a so n ry o r o n g ra de M as o n ry G ro und flo o r sl ab s u sp e nd ed o r o n g ra de C ol u m ns , be am s & s h ea r pa ne l s tr u ct ur e F ra m e d st ru ct ur e o r on g ra de G ro un d flo o r sl ab s us pe n de d C ol u m ns , be am s & s h ea r pa ne l s tr u ct ur e S u sp e nd ed g ro un d fl oor sl ab w ith c ra w l s pac e C ol u m ns , be am s & s h ea r pa ne l s tr u ct ur e S u sp e nd ed f irs t f lo o r sl a b G ro un d fl oo r sl a b su sp e nd e d o r on g ra d e S us p e nd ed f irs t flo o r sl a b G ro un d flo o r sl ab s us pe n de d o r on g ra de S us p e nd ed g ro un d fl oor sl ab w ith c ra w l s pace F ra m e d st ru ct ur e F ra m e d st ru ct ur e
G ro un d fl oo r sl a b su sp en de d or s la b on g ra de S us p en d ed fi rs t f lo or s la b G ro un d le ve l c ol um ns , b ea m s & s he ar p an el s tr uc tu re F irst l ev el m as on ry G ro un d fl oo r sl a b su sp en de d or s la b on g ra de G ro un d le ve l f ra m ed s tr uc tu re F irst l ev el m as on ry S us p en d ed fi rs t f lo or s la b C ra w l s pa ce fr am e d st ru ct ur e S us pe nd ed g ro un d flo o r sl ab C ra w l s pa ce c ol um ns , b ea m s & s he ar p a ne l s tr uc tu re F irs t l ev el m as on ry S us pe nd ed g ro un d flo o r sl ab F irs t l ev el m as on ry
S
lo
p
in
g
s
ite
F
la
t
si
te
2
le
ve
ls
S us pe nd ed g ro un d fl oo r sl ab C ra w l s pa ce f ra m ed s tr uc tu re F ir st le ve l m e ta lli c st ru ctu re G ro u nd le ve l f ra m e d st ru ct u re F ir st le ve l t im be r S us pe nd ed f irs t flo o r sl ab C ra w l s pa ce c ol u m n s, b ea m s & s he ar p an el s tr uc tu re G ro u nd le ve l c ol u m n s, b e am s & s he a r p an e l s tr uc tu re F irs t l ev el c o ld f or m ed ste e l S us pe nd ed g ro un d fl oo r sl ab F ir st le ve l t im be r S us pe nd ed f irs t f lo o r sl a b S u sp en d ed g ro u nd fl oo r sl ab O ne le ve l t im be r G ro un d flo o r sl a b su sp e nd ed o r o n g ra de S he ar p an el w ith c ra w l s pa ce F irs t le ve l t im be r S us p en de d fir st fl o or s la b G ro un d flo o r sl ab sus pe nd ed F ir st le ve l t im ber o r o n g ra de
4.2 Design criteria
4.2.1 Conventional design
--- Buildings and structures, and all parts thereof, shall be constructed to support safely all loads, including dead loads.
--- Where different construction methods and structural materials are used for various portions of a building, the applicable requirements of this part for each portion shall apply.
4.2.1.1 Conventional building
--- Conventional construction shall be considered as building with acceptable shape of the Figures 12,
13 and 14, “1 and 2 level house type”.
--- All conventional construction shall be designed in accordance with this code.
4.2.1.2 Irregular building
--- Irregular buildings shall have an engineered lateral-force resisting system designed in accordance with accepted engineering practice.
--- A building shall be considered to be irregular when one or more of the following conditions occur: a) When exterior shear panels or reinforced frame is not in one plane vertically from the foundation to the
uppermost story in which they are required. (See Framed structure)
b) When a section of floor or roof is not laterally supported by shear panel or reinforced frame on all edges.
c) When an opening in a floor or roof exceeds the lesser of 3.60m or 50% of the least floors or roofs dimension.
d) When portions of a floor level are vertically offset.
e) When shear panel or reinforced frame is do not occur in two perpendicular directions.
f) When shear panel or reinforced frame are constructed of dissimilar bracing systems on any one-story level above grade.
--- Limit of this code:
When a building of otherwise conventional construction contains structural elements, which exceed the limits of this code, those elements shall be designed in accordance with accepted engineering practice.
4.2.2 Engineered design 4.2.2.1 General
Buildings shall be constructed in accordance with the provisions of this code as limited by the provisions of this section.
4.2.2.2 Wind design.
The requirements in this document are based on design wind speed over open water at equivalent elevation of 10m average over 10 minutes with a recurrence of one in 50 years.
4.2.2.2.1 Minimum load
Table 1 - Design pressure for winds
Design pressure Trinidad Tobago
Wind zone (Consensus conference) Zone 2 Zone 3
Wall (horizontal load) kN/m
²
0.80 1.00Roof (minimum uplift) kN/m
²
1.00 1.454.2.2.2.2 Site effect
--- The pressure above shall be modified to take in consideration the site effect in 3 categories.
Site types Protected Normal Exposed
Coefficients 0.80 1 1.35
--- It is considered as exposed , costal site until 5km from the sea or top of hill or ridge, E W valley and special site well now for this exposure.
--- It is considered as protected area small building in down town or in special valley N S (This coefficient must be used with caution and the help of the Engineer).
4.2.2.3 Seismic design
All buildings shall be constructed in accordance with the provisions of this section.
Seismic design category: 4.2.2.3.1 Ground acceleration
The requirements in this document are based on maximum ground acceleration associated with 10% probability of occurrence in 50 years. Trinidad and Tobago in Zone 3 (Consensus conference).
for Trinidad 0.3 g
for Tobago 0.3 g
b) Soil liquefaction
To prevent any soil liquefaction on the same type of land than above a special attention shall be carried out with an engineer specialist for the choice of the appropriate type of foundation. See calculation for shear load.
4.2.2.3.2 Weights of applied finishes
--- Dead load finishes shall not exceed 1 kN/m2 for roofs or 0.5 kN/m2 for floors. --- Dead load finishes for walls above grade shall not exceed:
a - light-frame walls
0.75 kN/m2 for exterior
0.50 kN/m2 for interior
b - masonry walls
2.50 kN/m2 for 150mm thick masonry wall
3.80 kN/m2 for 200 mm thick masonry wall
c - concrete walls
4.10 kN/m2 for 150 mm thick concrete walls
4.2.2.3.3 Height limitations
The design applied to any construction is limited to two stories with a maximum of 9m to the top of the building.
4.2.2.4 Flood plain construction
Buildings and structures constructed in flood prone areas as established in Fig. 15 & 16 shall be designed and constructed in accordance with Clause - Flood resistant construction and Clause - Coastal high hazard areas of Part "Minimal requirements".
4.2.3 Dead load
The actual weights of materials and construction shall be used for determining dead load with consideration for the dead load of fixed service equipment.
4.2.4 Live load
The minimum uniformly distributed live load shall be as provided in Table 2.
Table 2 - Minimum uniformly distributed live loads
Use Live loads
(kN/m2)
Domestic floor - All rooms excepted above 1.5
Office floor – excepted above 2.5
Small industrial and storage 5
Exterior and interior balconies, Corridors & Stairs 5
Use Horizontal loads
(kN/m)
Fig A2-3 Trinidad flood prone areas
Fig 15 – Trinidad flood prone area
SWAMP
HIGH
OCCASIONAL
SLIGHT
T O B A G O S c a r b o r o u g h # # R o x b o r o u g h S to re B a y # P ly m o u th T u rtle B e ac h # Lo u is D 'o r # # B u c c o o # A r g y le # Lo w la n d s P a r is h e s 2 0 0 2 0 4 0 M i le s N E W S
Area Impact / Recurrence
interval
Cause Tobago north side Buccoo 9m of limestone cliff
eroded Flora 1953
Coastal/Tidal
Tobago south side Tobago south side Tobago north side Tobago north side
Tobago north side Tobago north side
Roxborough Argyle Plymouth Turtle Beach Grange Bay Store Bay Pigeon Point 1999 H. Lenny feeder band
4.2.5 Roof load.
Roof shall be designed for the live load indicated in Table 3.
Table 3 - Minimum roof live loads (kN/m2)
Tributary loaded area for any structural members
Area (m2) Roof slope
0 to 20m2 20 to 55m2 over 55m2
Flat or rise less than (20°) 36% slope 1 0.75 0.6
Rise (20°) 36% to (45°) 100% 0.75 0.7 0.6
Rise greater than (45°) 100% 0.6 0.6 0.6
4.2.6 Lateral load design 4.2.6.1 Preamble
--- Wind and earthquake introduce horizontal loads in the superstructure that are transferred to the foundation. We have to consider 2 steps:
a) Transfer of the horizontal load from: i. wind to vertical wall and roof.
ii. acceleration of mass located everywhere in the superstructure to the appropriated wall or framed structure.
b) Transfer of the load from the top to the bottom of the wall or superstructure and the foundation.
--- According to this code:
a) horizontal transfer is done by horizontal diaphragm or horizontal beam and slab. b) vertical transfer is one by shear panel, cross, or framed structure.
4.2.6.2 Diaphragm
--- Floor, roof or ceiling assemblies may be constructed with the necessary stiffness and load path continuity to distribute lateral loads (wind and earthquake) to lateral support subsystems. In this role, floor, roof or ceiling surface act as horizontal beams (also called a diaphragm) spanning lateral supports points. --- Use of floor, roof or ceiling assembly, as a diaphragm requires both strength and stiffness properties and development of connections to transfer the diaphragm force.
This consideration is very important to complete the role and action of the shear panel.
Part plan Part elevation Part elevation In situ concrete In situ concrete 400 In situ concrete ground level 1 800 40 0 1 00 0 1 60 0 Minimum L1=1000
2 diam. 12 every 2 rows 5 diam. 12
Shear panel
in 2 parts
Shear panel
in one part
15 0m m m in L2 = 2400 - L1 ground levelFig 18 - Shear panel - Horizontal core blocks
Part plan Part elevation In situ concrete ground level 1 800 1600 max 2100 min 250mm minRing beam concrete and reinforcement 500
11 5 200 4 dia. 12mm Part elevation ground level
Ring beam concrete and reinforcement
Part elevation ground level 150 min Limit of opening location 6mm stirrup each 150mm
Shear panel in two parts
Shear panel in one part
L1 = 1000 min L2 = 2400 mm - L1
m
m
4.2.6.3 Shear panel
4.2.6.3.1 Concrete shear panel in wall
A shear panel (see Figures 17 and 18 - Shear panel) is a portion or section of a 150mm exterior wall that performs the function of resisting lateral earthquake or wind forces.
4.2.6.3.2 Timber
See Section - Wall bracing.
4.2.7 Load factors
All structures shall resist combined loads as follows:
4.2.7.1 Gravity 1.40 D + 1.70 L 4.2.7.2 Earthquake a) 0.75 (1.40 D + 1.70 L +/- 1.87 E) and b) 0.90 D +/- 1.43 E
4.2.7.2.1 Shear load calculation
--- A simplified formula, for this code is:
V = 0.05 x S x W x A total shear in kN
--- Whereas:
The 0.05 coefficient integrated the Z = ground acceleration, C = amplification factor due to structure frequency, I = importance factor = 1 in this code and Rw = ductility factor related with respect to the column design reinforcement used in the normal practice formula.
S = site factor
S = 1 for good soil (rock, gravel) S = 1.2 for softer material (clay, fill) S = 1.5 for deep alluvial deposits
S = 2.5 maximum for reclaimed land and saturated soils (due to the amplification factor)
W = total load in kN
4.2.7.3 Wind 1.40 D + 1.70 L + 1.75 W Note : D = dead load L = live load E = earthquake load W = wind load 4.2.8 Deflection
The allowed deflection of any structural member under the live load shall not exceed the following values in Table 4.
Table 4 – Maximum deflection authorised.
Floor slab, structural beam and ceilings L/360
All others structural members L/240
Rafters and purlins L/180
Interior walls and partitions H/180
Notes:
L = span length H = span height
4.3 Minimal requirements
4.3.1 Site address
4.3.1.1 Premises identification
Approved numbers or addresses shall be provided for all new buildings in such a position as to be plainly visible and legible from the street or road fronting the property.
4.3.2 Light
4.3.2.1 Habitable rooms
All habitable rooms shall be provided with an area to allow natural light to enter not less than 10 percent of the floor area of such rooms.
4.3.2.2 Adjoining rooms
For purpose of determining requirements of light, any room shall be considered as a portion of an adjoining room when at least one-half of the area of the common wall is open and unobstructed and provides an opening of not less than 10% of the floor area of the interior room but not less than 2.50m2.
4.3.2.3 Bathrooms
Bathrooms, water closet compartments and other similar rooms shall be provided with an area to allow natural light to enter not less than 0.25m2.
4.3.2.4 Stairway illumination
--- All interior and exterior stairways shall be provided with a means to illuminate the stairs, including the landings and treads.
--- Interior stairs shall be provided with an artificial light source located in the immediate vicinity of each landing at the top and bottom of the stairs.
--- Exterior stairs shall be provided with an artificial light source located in the immediate vicinity of the top landing of the stairs.
4.3.3 Ventilation
4.3.3.1 Natural ventilation 4.3.3.1.1 Habitable rooms
--- Natural ventilation shall be provided in all habitable room through windows, louvers or other natural openings through the external wall to the outdoor air.
--- The minimum area of ventilation shall be not less than 15% of the floor area of such rooms, of which of 5% shall be fix ventilation.
4.3.3.1.2 Adjoining rooms
For purpose of determining ventilation requirements, any room shall be considered as a portion of an adjoining room when at least one-half of the area of the common wall is open and unobstructed and provides an opening of not less than 15% of the floor area of the interior room but not less than 2.50m2.
4.3.3.1.3 Bathrooms
Bathrooms, water closet compartments and other similar rooms shall be provided with a ventilation area not less than 0.25m2.
4.3.3.2 Mechanical ventilation 4.3.3.2.1 Principle
--- The centralised ventilation system ensures air renewal to keep the occupants healthy and to protect the building from being damaged by the moisture. A quiet and continuous ventilation of the house is provides an incomparable indoor air quality to the house.
--- The system consists of a central extract unit connected to the exhaust grilles by spiral ductwork. Fresh air is introduced into bedroom and lounge through self balancing inlets. Fresh air inlets are fitted either straight across the wall or as trickle vents. Stale air is extracted into the high moisture producing rooms (kitchen, bathrooms and toilets) through self balancing exhaust outlets.
--- The centrifugal fan unit is located on the roof or in the loft space and is connected to galvanised metal ducting to outside.
4.3.3.2.2 Habitable rooms
--- All habitable rooms shall be provided with the minimum ventilation rates of 30m3/hr for continuous ventilation for every 12m2 of the floor area or part of such rooms.
--- This ventilation shall be through windows, doors or other natural openings through the external wall from the outdoor air through a special 30m3/hr-air regulator.
4.3.3.2.3 Kitchen and bathrooms
--- All the air introduced into the house through the habitable rooms (e.g. Living, dining, bedroom, corridor and entrance) shall be extracted in the rooms e.g. kitchen, bathroom, toilet, washing room and other similar rooms have to be maintained in depression to create an air flow through the house.
--- The minimum exhaust airflow for each room is as follows: Kitchen 120 m3/hr
Bathroom 60 m3/hr
Shower 60 m3/hr
Toilet (WC) 30 m3/hr Washing room and store room 30 m3/hr
--- This ventilation air shall be exhausted permanently and directly outside.
4.3.3.2.4 Internal doors
All internal doors have to be provided with air passages not less than 150 cm2. Note: These passages can be provided with a bottom gap of 20 or 25mm under the door.
4.3.3.2.5 Minimum global ventilation
For each house or apartment the minimum ventilation rate is one volume per hour of the habitable part of the house.
4.3.4 Minimum room sizes
4.3.4.1 Habitable rooms
--- Every dwelling unit shall have at least one habitable room (living or sleeping room), which shall be not less than 12m2 of floor area.
--- Other habitable rooms shall have a gross area of not less than 7.50m2.
4.3.4.2 Other rooms
Kitchen not less than 5m2
Bathroom not less than 3m2and not less than 2m2 for the second one Shower not less than 1.5m2
Toilet (WC) not less than 1m
²
WC for handicapped people the minimum area must be3m
²
See Figures: 20 - Minimum room sizes, 21 - Typical furniture arrangement and 22 - Typical arrangement 7.5m2 room.
Fig 20 - Minimum room sizes
2500mm minimum 3000mm 3464mm square 4800mm 4000mm 3464mm 3000mm 2500mm minimum 2739mm square 2739mm 1800mm min 2778mm 2143mm 1400mm min 900mm min 750mm min 1667mm 1333mm 1732mm square 1732mm 2236mm 2236mmMain room
12m2 min
Other room
7.5m2 min
Kitchen
5m2 min
Bath.
3m2 min
Shower
1.5m2 min
WC
1m2 min
800mm 1250mm min1333mm
