Builder Fitting Insulation Into Roof Of New Home

Most homes are suitable for one form of insulation or another depending on your wall type and the condition of your loft, but often different rules apply on whether you are able to insulate your walls depends the product being used, wall type and condition.


Loft insulation

It is worth having a look in your loft to see if it is already insulated or can be insulated. It is recommended that you have 270mm of loft insulation and it is worth topping it up if it’s below 100mm. If your loft is converted, boarded or the loft hatch is inaccessible it won’t be suitable. You can either insulate the loft yourself or get an insulation company to do it.
Cavity wall properties
Distinguishing whether your walls are cavity construction or solid is determined by the brick pattern. If the bricks are in a regular pattern length ways throughout the wall then it is likely to have a cavity. If the walls are covered then you can measure the width of the wall and if it is over 260mm then it is likely to have a cavity. Those with a cavity wall construction should be able to be filled with insulation. An insulation company will do a survey prior to filling the cavity and will put a borescope into the wall to check if it’s already filled with insulation and clear to fill it.

Solid wall properties

To determine if the walls are solid, check the brick pattern, if they form an alternating pattern then the wall is solid. Solid walls can still be insulated but they can’t be filled and would have to be internally or externally insulated. Internal insulation will reduce the size of your rooms and would be disruptive. External wall insulation is less intrusive but does require additional checks with the council.

Non-standard construction

If you live in a timber or steel-framed property, stone property or pre-fabricated property then they are unlikely to have a cavity in them or if they do they are probably not able to be filled. Some of these build types can be treated the same as solid wall properties, however, different planning rules may apply and you should seek expertise advice on whether the property is suitable. In particular, in the case of stone properties these are often prohibited from having external wall insulation by some councils as it changes the look of the property.


If you are able to insulate your home you could save between £10-225 per year with loft insulation, according to the Energy Saving Trust, this varies depending on the size of the property and how much insulation is already present. Cavity wall insulation could save you £70-225 per year and solid wall insulation £120-425 per year depending on the size of the
It is also worth checking if you are eligible for free insulation as people who are in receipt of certain benefits are eligible for grants to cover or contribute to the cost of insulating their home.

house insulation concept. copy space