What statutory approvals do you need for retrofitting new wall insulation?
Are you considering improving the thermal efficiency of your home through new wall insulation? If so, great idea! Approximately 35% of heat loss in a house is lost through the walls, which accounts for more heat loss than the other building elements individually. Retrofitting new insulation to your walls can help reduce this to improve thermal comfort in your home and reducing your energy bills.
However, before you install the insulation, you may need two different statutory approvals: planning permission and a building warrant. These are two separate permissions, requiring two separate applications.
Planning Permission
In general, permitted development rights will allow you to install anything within a 1m bubble of your home without need for permission. This means that you can install external wall insulation without needing consent. You can also make internal alterations to your house without requiring planning permission, so internal wall insulation and cavity wall insulation are permitted.
However, there are some cases where this does not apply. If you live in a conservation area, permitted development rights are restricted, and you will need planning permission to install external wall insulation. If your house is listed, you will need planning permission and listed building consent to make any alterations, including all types of new wall insulation.
Depending on your local area, there may be other conditions where planning consent may be required for installing new wall insulation. It is always best to check with your local planning department prior to starting any work.
Building Warrant
If you are installing external wall insulation, you will need a building warrant. This is primarily due to two reasons: to ensure that the system is structurally sound and will not fall off, and to ensure the system will not cause an increased risk of fire.
If you plan to instal an external thermal insulation composite system (ETICS), it is likely that the manufacturer will have the required information. However, if you plan to install a bespoke system, you will need this to be properly designed and specified by professionals.
While you do not need a building warrant to install internal wall insulation and cavity wall insulation, it is important that the system is designed by a professional with retrofit experience. These types of wall insulation have a higher risk of creating interstitial condensation, which can degrade the structural integrity of your home. While a building warrant may not be required, the work must still meet building regulations, and additional ventilation may be required.
If you have any doubt about wither you need permission to upgrade the insulation in your home, it’s always best to get advice first. This could be from a professional working in the sector, or from your local council.
This post concerns Scottish regulations, and may not apply to other areas