How to Eco-fit a Building : Insulation

Eco-fitting is the retroactive process of improving the sustainability and energy efficiency of an existing building. So, how to eco-fit a building? 

Older buildings are often inherently green in the way they have been constructed, using locally sourced, sustainable materials. However, they are also drafty and poorly insulated.

Grand Designs magazine asked me to contribute to an article about how to eco-fit a building in order for it to perform to modern standards of energy use. I thought I would explain some of my thoughts here.

How can we save energy, whilst providing comfortable, inhabitable spaces within an older building?

The most obvious way of eco-fitting older buildings in order to make them more energy efficient is to insulate them. However, this is not as simple as it sounds.

One of the difficulties with adding insulation to structures is allowing the building fabric to breathe. This is particularly important with an existing or historic building, which might have solid walls, for example.

Historic structures were built from natural materials in harmony with their environment. Inherently draughty, moisture was able to be escape from the building. Traditional lime mortars and renders actively draw away moisture from saturated masonry. Adding insulation can impact on the breathability of building fabric. Makings buildings air tight in order to minimise heat loss, further impacts on this ability. When a cold surface meets a warm surface, condensation can occur. When this condensation is trapped inside building fabric and is not able to escape it can cause corrosion, most commonly in walls and roofs.

Therefore, whether new build or retrofit, as part of an eco-fit process measures should be taken to maintain breathability allowing any condensation to escape.

This is just one of the many complex aspects that architects consider when preparing their construction details.

As ever, if you would like to discuss a particular issue about how to eco-fit  a building or a potential project please do get in touch.