Example energy performance requirements, Norway 163

To exemplify how energy performance requirements could be reflected in national regulations, an extract of the key requirements in the latest Norwegian building regulations is presented below.

1. The building regulations apply for all new buildings and renovation of existing buildings

2. The same regulations apply for the whole country without adjustments for climatic differences

3. Energy performance is calculated according to national calculation methodology in compliance with IS 13790 and “Oslo climate” (4.000 degree days) Two ways of documenting compliance with the building regulations, at least one must be fulfilled:

1. Overall Energy Performance

2. Specific quality of the building envelope and technical building systems

Figure 7.1-1 Variations in degree days in Norway

South Inland South Coastland South High mountains Middle Inland Middle Coast North Coast North Inland 6.600 degree days (Kautokeino) ° Oslo

3.000 degree days (Stavanger)

1. Overall energy performance requirements

Maximum kWh/m2 year for different building categories (energy need for heating and DHW plus energy use for fans, pumps, lighting and appliances):

Table 7.1-2 Norwegian overall energy performance requirements Building category Maximum kWh/m2 · year Single family house 120 + 1 600 / m2 _{heated area}

Block of flats 115

Kindergarten 140

Office building 150

School 120

University / high school 160

Hospital 300 (335)* Nursing home 215 (250)* Hotel 220 Sports facility 170 Commercial building 210 Cultural building 165

Light industry / workshop 175 (190)*

*: For areas where heat exchange of ventilation system leads to risk for spreading of contamination and areas where heat exchangers can lead to spreading of contamination

164 When making calculations to document compliance with the “Energy Performance” requirements, the following adjustments can be included:

• For ventilation systems with VAV (Variable air volume) controlled by CO2 sensors, the calculation of annual energy need for heating / cooling can be based on 20% reduced air flow during working hours.

• If the lighting systems are equipped with automatic daylight control and presence sensors, the calculation of annual energy need and heat load for lighting can be reduced with 20%.

Additional, specific requirements: 1) Building envelope

Table 7.1-3 Norwegian additional, specific requirements

Maximum U-values (W/m2_{·K) Air leakages}

Wall Roof Floor (ground or elevated floor)

Windows and doors incl. frames

Leakage number at 50 Pa (air change/hour)

0,22 0,18 0,18 1,6 ≤ 3,0

2) Piping

Piping, equipment and ducts for the heating and cooling systems must be insulated with energy efficient insulation according to NS-EN 12828

3) Windows

U-values for glass/windows/doors including frames multiplied with the share of windows and doors of the total heated floor area must be less than 0,24

4) Sun factor

Total sun factor (the amount of solar radiation that passes screening and glass) for glass/window shall be less than 0,15 for sun exposed facades unless it can be documented that the building does not need cooling

2. Specific minimum requirements a) Transmission

Table 7.1-4 Norwegian minimum requirements to transmission Area of

windows + doors ≤ 20% of

floor area

U-values (W/m2_{·K) Normalised thermal bridges*}

Wall Roof Floor Window/door Single fam. house Other build. ≤ 0,18 ≤ 0,13 ≤ 0,15 ≤ 1,2 ≤ 0,03 W/(m2·K) ≤ 0,06 * total heat loss through thermal bridges divided by heated floor area

b) Infiltration and ventilation heat losses

Table 7.1-5 Norwegian minimum requirements to leakage Leakage at 50 Pa pressure difference

Single fam. house Other buildings

165 For residential buildings the requirements in a) and b) can be internally adjusted, as long as the building’s heat transfer (loss) number does not increase. For other buildings the requirements in a) can be internally adjusted, as long as the building’s heat transfer (loss) number does not increase.

Heat transfer (loss) number = H” (W/(m2_·K))

c) Other measures

Setback: Possibility for night and week end temperature setback Cooling: Measures are done to avoid need for local space cooling Requirements for the heat supply of a building:

1) Boiler

It is not allowed to install boiler using oil to cover the base load (60–90% of total energy need). Oil is only allowed to cover peak load.

2) Renewable energy sources

Buildings > 500 m2 heated area must be designed and built so that minimum 60% of the net energy need for heating is covered with other energy sources than direct electricity or fossil fuel.

For buildings ≤ 500 m2 _{the minimum is 40%.} Exemptions:

Requirements in 2) are not enforced if:

• it can be documented that environmental conditions make it impossible to reach the requirements in a practical way

• for residential buildings with an energy need < 15.000 kWh/year.

Residential buildings that are exempted must have chimney and closed fireplace for bio fuel. This, however, is not required for residential units smaller than 50 m2 heated area or for residential buildings that are built as passive houses.

District heating:

In areas having a district heating, all new buildings must be equipped with systems that can utilise district heating for:

• heating;

• ventilation (heating);

• domestic hot water.

Other specific energy efficiency requirements. To ensure energy efficient operation:

• General requirements for heating and cooling systems: Heating and cooling systems must have equipment for temperature control to obtain energy efficient operation

• Central heating systems: Water based heating systems connected to district heating or heat pumps must have water temperature control system so the temperature can be adjusted to obtain energy efficient heat production

• Heat pump and cooling plants: Heat pumps and cooling plants (chillers) must have automatic control systems to obtain energy efficient operation

• Piping, equipment and ducts for heating and cooling distribution systems that are emitting unexploitable energy (heating/cooling) must be insulated with energy efficient insulation

166 according to NS-EN 12828. (Heating systems in buildings / Design of water based heating systems)

Minimum ventilation rates:

Table 7.1-6 Norwegian minimum requirements to ventilation rates

Operation period Domestic buildings

Buildings for the public and working places* a) Ventilation for human need b) Emission from building

parts and furniture Occupancy 1,2 m3/h·m2 26 m3/h per person (light

activity)

2,5 m3/h·m2

Non occupancy 0,7 m3_/h·m2 _{0 0,7 m}3_/h·m2

* Total requirement is the sum of a) and b)

Heat exchangers must be installed in all new ventilation systems. Efficiency requirements: Table 7.1-7 Norwegian minimum requirements to heat exchanger efficiency

Residential buildings and areas where heat exchangers can lead to spreading of contamination

Non-residential buildings

Efficiency ≥ 70% Efficiency ≥ 80%

Specific fan power:

Table 7.1-8 Norwegian minimum requirements to specific fan power Residential buildings Non-residential buildings

≤ 2,5 kW/(m3/s) ≤ 2,0 kW/(m3/s)

The Norwegian building regulations have no special energy efficiency or energy performance requirements for:

¾ Domestic hot water ¾ Lighting systems

¾ Other energy consuming building equipment ¾ Energy management / energy monitoring ¾ Co-generation

167