In our well intended path towards energy efficiency we quite logically assume that insulation is a good idea. In our quest to improve the thermal envelope we also assume that more insulation is better. With these good ideas in mind we then go and invest a fair amount of money on insulation.
These ideas are good but there is more to it than just throwing insulation into the building.
If you want the insulation to perform to its full potential you must do two things:
- Make sure it is installed properly.
- Apply air tightness to the building envelope.
Without doing these two things the insulation will underperform. No good deed will go unpunished. Paying for good insulation that doesn’t perform is a waste of money.
Make sure it is installed properly: Insulation should be installed with no gaps. When installing insulation batts in a wall assembly, all six faces of the batt should be touching a surface. Where electrical and plumbing services are in the wall cavity, the batt should be split to encase them. Neglected areas such as header lintels and external frame pockets should be insulated. Click here for more information on insulating.
Apply air tightness to the building envelope: If insulation has air rushing through it, it doesn’t work very well. Moisture laden air will also decrease the effectiveness of the insulation and potentially lead to structural decay and mould. An airtightness strategy applied to the building envelope will avoid these problems and allow the insulation to function to its full potential. Click here for more information on insulation & airtightness. (When applying airtightness, don’t forget about moisture management).
So, what’s the lesson? Stick to the good ideas of providing insulation, but make sure you do the two things as mentioned above to ensure that the money you spent on the insulation isn’t wasted.