Architect's Zone
What are the Energy Building Regulations?
Main implications of the 2007 Part L Building Regulations (Amended)
The 2007 update to Part L of the building regulations will have a significant impact on how dwellings are constructed in Ireland. The Irish Government has committed to reduce CO2 emissions by 40% as required by its commitments to the Kyoto protocol.
Particular attention will be paid to the quality of workmanship on site. A little extra care and attention will be needed to ensure insulation is installed correctly; unnecessary openings in the building fabric are sealed to avoid unwanted draughts. The good news is that all of this extra attention will result in more energy efficient buildings, lowering our fuel costs and reducing our impact on the environment.
To this end the amended building regulations stipulate the following changes…..
Building Energy Rating
Each building must have a Building Energy Rating Certificate. A BER is carried out by a registered BER Assessor, contact www.sei.ie for more information on the BER process.
A BER will indicate the expected energy consumption of your dwelling in kilowatt hours per square meter per year. (kWh/m2/yr)
The BER certificate will also indicate the CO2 emissions from the dwelling against a reference standard.
Note that you cannot fail a BER; it is a rating (from A to G) based on the estimated energy use of your home.
Renewables
The next major change is the mandatory incorporation of a renewable energy source in the dwelling. The regulations require 10kWh/m2/yr for hot water heating and cooling systems. This requirement may be met with biomass or solar thermal systems.
Or
4kWh/m2/yr of electrical energy or a combination of these which would have equivalent effect.
The 4kwh/m2 / yr from electrical systems may be met by heat pump, wind energy or solar photovoltaic installations.
Air Tightness
For the first time in Irish construction regulation a system for checking the final build quality has been introduced. Air Tightness testing, more correctly referred to as unwanted air infiltration testing allows the home owner to quantify the level of unwanted air that may penetrate the building fabric. This air may result in heat loss, draughts reducing the energy efficiency of the building.
The regulation stipulates a pass rate of 10 air changes per hour or less based on pressurising the house to 50 Pascals. Typicaly a house constructed with reasonable attention to detail will pass this requirement. However it is possible to achieve much lower values without too much trouble. A low energy house will achieve 2 or less air changes per hour at this level of air Tightness the building may require a mechanical ventilation system to ensure adequate supply of fresh air.
Insulation
Previous Building Regulations allowed the builder to carry out an overall heat loss calculation and in some cases reduce the insulation levels in certain elements, however this compliance method has now been eliminated and it is necessary to comply with the Elemental values in all instances, the U values required for the building elements are shown below.
Aerobord has a wide range of insulation solutions that will meet or exceed the value below.
Element |
U value |
Floor |
0.25Wm2K |
Wall |
0.27Wm2K |
Pitched Roof (insulation at ceiling level) |
0.16Wm2K |
Pitched Roof (insulation on slope) |
0.20Wm2K |
Flat Roof |
0.22Wm2K |
Thermal Bridging
More care will have to be taken to eliminate any thermal bridges. Workmanship will play an important role in this mission. It will be necessary to ensure that insulation is properly fitted and greater attention is paid to detail. The Department of the Environment have issued Irish Robust Details which will be the mandatory standard for all Irish building.
Heating Controls
Energy efficient space and water heating systems with efficient heat sources and effective controls are to be used.
- Automatic control of space heating on basis of room temperature.
- Automatic control of heat input to stored hot water on basis of stored water temperature.
- Separate an independent automatic time control of space heating and hot water.
- Insulation of hot water pipes and storage tanks.
Boiler Efficiencies
All oil and gas fired boilers must have a minimum seasonal efficiency of 86%. All replacement oil and gas fired boilers also must have a minimum seasonal efficiency of 86%.Home energy manual
The owner must be provided with sufficient information about the building and the installed systems (inc. maintenance) to ensure it is run efficiently.
ABC Energy Ratings
