Most people we speak to have some pretty strong views on solid wall insulation which seem to largely be based on the experience of someone they know, on aesthetic preferences, or on on concerns about damp (some people think internal will prevent damp, others think external solves the problem). All are valid factors to consider.
For the large majority of ECO4 customers, internal wall insulation will be the best option. Here’s our view on why.
Cost
External wall insulation costs at least twice as much as internal insulation. Because of the way funding is allocated per property (based on the improvement achieved to your home, not the cost of the products you need to achieve the benefits), most properties need to contribute to the cost of external wall insulation. There are some that might still work though, depending on if your roof has enough overhang without alteration. For those who don’t though, we’ve seen quotes from £7k-15k recently.
Maintenance
If there is a problem in the future, it is just has expensive to get it repaired. It’s also hard to find contractors who do the work, because of the level of difficulty.
Internal wall insulation is (almost!) always covered completely by ECO4 funding. If it gets damaged at any point in the future, your local plasterer will be able to patch up most issues at minimal cost.
Aesthetics
Particularly in rural areas where ECO4 is most active, solid wall houses are often gorgeous stone buildings, or stone facades, or sometimes brick. There is character most people prefer to keep.
Concerns about Internal Wall Insulation
The main problem with internal wall insulation is present in smaller houses. On your externally facing walls you lose 52mm. Interestingly, most customers don’t seem to notice the difference. Maybe they are too pleased with the warmth the home now offers?
Ventilation is key either way. Stone properties need to breathe, so expect to talk to your surveyor about trickle vents and fans, if needed. Ventilate to insulate is a strong slogan in the industry.
There will always be examples when people can’t have internal insulation for specific reasons. Unfortunately, unless Ofgem and the energy companies change the way funding works, we don’t have better news for those people.
We believe it’s always best to have a call with an assessor to understand your options and potential eligibility. Whether you have solid or cavity walls, please feel free to call us for an initial chat.