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  • ENERGY ASSESSOR
    • AIR LEAKAGE SURVEY
    • THERMAL BRIDGE ASSESSOR
    • EPCs & ENERGY ASSESSOR
    • THERMAL CAMERA SURVEY
    • CODE FOR SUSTAINABLE HOMES ASSESSOR
    • DOMESTIC REFURBISHMENT ASSESSOR
  • HEALTHY DESIGN
  • VENTILATION
  • CASE STUDIES & INFO
    • 3 BED SEMI - 1990'S
    • 3 BED SEMI - 1960'S
    • 3 BED TERRACE - 1930'S
    • AIR TIGHTNESS IN EXISTING DWELLINGS
    • DAMPNESS AND CONDENSATION
    • GRANTS FOR BOILER REPLACEMENT
    • HOW ENERGY EFFICIENCY CREATES JOBS
    • HOW THE EPC EFFECTS HOUSE PRICES
    • LOW ENERGY LIGHTING
    • PHOTOVOLTAICS
  • CONTACT & PEOPLE
our warm home road map
1 hot water cylinder insulation
2 energy efficient lighting
3 heating controls
4 air tightness
5 insulation
6 mechanical (boiler, etc)
7 behaviour
8 renewables
hot water cylinder, save £50-£75
An 80mm thick hot water cylinder insulation jacket costs around £15 and when placed over the existing cylinder insulation should save you at least £50 a year. You will save even more if you insulate the pipes between the boiler and the cylinder and any pipes around the cylinder. Try to ensure there are no gaps. Pipe insulation costs between £1-2 a meter. As the hot water in this cylinder is kept above 60°C, the longer you can keep it hot, the more money you will save. 
replace light bulbs, save £100-£150
Old style incandescent light bulbs can now be replaced with LED bulbs for £8 to £12 each. The LEDs will come on instantly and will reduce your lighting costs by up to 90%.
For a house with 12 lights it would cut your electricity bill by £100 a year. LED lights last for up to 20 years.
heating controls, save £150 - £200
Fitting a thermostat to your heating system will turn your boiler and heating pump off when the set temperature is reached. This is known as a boiler interlock and will save you £125 a year. Fitting a thermostat to a pin clock timer will cost around £50.
A programmable thermostat will cost around £100 to install. Thermostatic Radiator Valves turn the radiator off when the required temperature is reached saving you money by preventing any room overheating.
draught seal & save £100 a year
The average dwelling has total gaps & holes the size of 5 basketballs (an air leakage rate of around 12m³/hr/m²). Draught sealing your dwelling could seal up 1 or 2 basketballs sizes of gaps and save you £100 a year.
A commercial property generally has 8 basketballs.
missing insulation - save £100 a year
A 5% gap in insulation will cause up to a 40% drop in performance. 
As warm air rises it is particularly important to prevent this heat escaping through the attic. The ceiling must therefore be well sealed, there should be no areas of missing attic insulation, the trap door must be draught sealed and insulated and there must be insulation over the ceiling joists. Fixing the attic insulation will save £100 a year.
boiler replacement, save £210 a year
For average Homes with Oil Central Heating and an older non-condensing boiler with an efficiency of around 75%, the dwelling would need 2,500 litres of oil costing £1300.
Upgrading to an 'A' rated condensing boiler with an efficiency over 90% would save over 400 litres of oil and £210 a year. 
To replace an oil boiler can cost around £1,500 depending on the works involved. Grants of £400 to £1,000 are available from the Housing Executive to replace boilers.

An 'A' rated Gas Boiler will save you an additional £100 a year over an 'A' rated Oil Boiler as Natural Gas is cheaper.
behaviour, save £100 a year
Turning your heating down by 1°C should save around £100 a year. Living Rooms or Kitchens could be set to 21°C and bedrooms at a lower temperature of 19°C.
Thermostatic Radiator Valves have settings of 1 to 5 with 1 = 5°C and 5 = 25°C. You should not be paying extra to have a room to warm.
£700 from photovoltaic panels
The roof on average size house will probably limit you to a 3KW photovoltaic installation. The full installation will cost under £5,500 and generate an income of around £700 a year, giving a payback of around 8 years. The £700 income is guaranteed for 20 years giving you a simple profit of around £8,000 after maintenance costs.
The PV panels are guaranteed to be more than 80% efficient after 20 years and will still therefore reduce your electricity bill by over £200 a year.
heat loss from house
The Average Energy Bill
In Northern Ireland the average dwelling has a heating and hot water bill of £1,100 a year which is a 20,000kwh heating demand.
The average electricity bill is around £630 a year or 3600 kwh (units of electricity).

The average domestic energy bill is made up as follows:
£775 heating 
£325 hot water
£130 lighting
£500 cooking & other appliances
TOTAL ENERGY BILL = £1,730
home energy use 2005
windy days versus freezing days
Does a building lose more heat on a freezing still day or a mild windy day?  
Unfortunately, as we have one of the windiest and mildest climates in Europe, a building with poor air tightness can lose up to 3 times as much heat on a mild windy day.
effective air tightness & insulation
Small gaps around or behind insulation can cause thermal performance to plummet by as much as 40%. The Sustainability Energy Performance of Ireland has reported that the difference in performance of dwellings with and without effective air tightness measures is 50%.To measure air tightness we will de-pressurise your home using a door blower fan and then use a thermal camera to identify air leaks and missing insulation.
thermal camera, heat loss ceiling