How to Calculate the Heat Loss in Your Home



Gallery

Heating (and in warm climates, cooling) are a large part of energy use, and this can be reduced dramatically by installing energy efficient windows and doors which will decrease energy costs and greenhouse gas emissions.

yourhome.gov.au writes that ‘Up to 87% of a home’s heating energy can be gained and up to 40% lost through windows’ and provides the following calculations:

The amount of heat conducted through a glazed unit (in watts; W) is calculated as Uw × T × A:

  • the U value (Uw)
  • multiplied by the number of degrees difference in air temperature on each side (T)
  • multiplied by the area of the glazing unit (A).

Example:

If your home has 70m2 of glazing with aluminium frames and clear glass with a U value of 6.2W/m2 °C, on a winter’s night when it is 15°C colder outside compared with indoors, the heat loss through the windows would be:

6.2 × 15 × 70 = 6510W

That is equivalent to the total heat output of a large room gas heater or a 6.5kW room air-conditioner running at full capacity.

If you choose a window with half the U value (3.1W/m2°C) (for example, double glazing with an argon-filled gap and less-conductive frames), you can halve the heat loss:

3.1 × 15 × 70 = 3255W

or a Paarhammer window with U value of 1.1

1.1 x 15 x 70 = 1155W,

This is one sixth of the first example of single glazing with aluminium frames and is well worth doing for energy cost savings as well as comfort.

Paarhammer Heat Containment

It is important to note that installing high performance windows alone is not enough. It is vital to see the whole envelope of a building as one and insulate each part, e.g. walls, underfloor and ceiling. Did you ever sit close to a single glazed window and felt the cold (or heat) coming through the glass? The solution is better insulation including high performance windows and doors which will keep temperatures at comfortable levels during extremes of hot or cold weather and provide thermal comfort.

 

Ready to talk high performance windows? Contact Paarhammer

MORE FROM Paarhammer Windows & Doors:
Avoiding Renovation Regrets

Avoiding Renovation Regrets

Australia's love affair with renovating is expected to continue not only because Australians love to renovate, but also as households increasingly prefer to direct excessive property transaction costs towards improving their existing homes, rather than trading up.
1 Shares
You May Also Like
This waterfront home leaves absolutely nothing to the imagination. Winning the Master Builders Association annual excellence in housing awards in the category of Design & Construct $2million+, this houses design has been superbly executed by the team at ACG Building.

Award-winning waterfront triumph

This waterfront home leaves absolutely nothing to the imagination. Winning the 2013-14 Master Builders Association annual excellence in housing awards in the category of Design & Construct $2million+, this house's design has been superbly executed by the team at ACG Building.