This is our third blog in our series exploring different aspects of retrofit. This one looks at insulation – and it’s a big topic! 

Most modern houses are now built with cavity wall insulation, but many homes from the 1950s onwards were built with empty cavities that have been filled more recently or could have cavity wall insulation installed. Not all of these are suitable for cavity wall insulation. Older properties tend to have solid walls, or cavity walls that are not suitable for filling with insulation. These properties may be suitable for insulation either internally or externally. 

It is also worth understanding the latest version of the Building Regulations – not all builders or plasterers realise that after taking off a certain percentage of the plaster off a wall, they may be obliged under the Building Regulations to insulate the wall. 

Some things to think about:

  • Adding insulation to a house (particularly an older property) may create problems with damp, if the wrong kind of insulation is used, or if the thickness is too great, or the insulation is not installed in the right way. 
  • Insulating the ground floor needs care too – it can cause the joists to rot if done in the wrong way! 
  • Insulating the loft with mineral wool between the joists is the most common, low cost way to reduce heat loss from a house – but there are some dos and don’ts. 
  • Not all forms of loft insulation are a good idea – spray foam on the underside of the tiles is risky and most mortgage lenders will not lend on a house with this installed. 
  • Always think first – do you need a designer or specifier? The average builder is not insured to decide how to insulate your home – they probably don’t have the qualifications or the necessary professional indemnity insurance. 
  • If you are installing windows and internal or external insulation, the position of the windows relative to the insulation really matters, so make sure you get it designed right. 
  • If you’re thinking about internal or external wall insulation, floor insulation, or insulating a room in the roof, you are making a big change to your home. It’s really time to make a whole house plan to make sure you get all the benefits and don’t suffer from the unintended consequences. We can help you with that journey here.

To find out more about insulation, take a look at our Eco-retrofit Webinar – #insulation (youtube.com) 

You can read the other blogs here: