Spray foam insulation has been heavily marketed as a fast, effective way to insulate lofts. Unfortunately, when applied directly to the underside of roof rafters, it can cause serious problems for your home — sometimes ones that don't become obvious for years.
If you've had spray foam installed, or you're thinking about it, here's what every homeowner in Berkshire should know.
What is spray foam loft insulation?
Spray foam is an expanding chemical foam applied directly to the underside of your roof, sealing between the rafters. There are two main types: open-cell foam (softer, breathable) and closed-cell foam (rigid, non-breathable). Both can cause issues, but closed-cell foam tends to be the more problematic.
The main problems with spray foam
1. It traps moisture against your timbers
Your roof relies on ventilation to dry out any moisture that enters the loft. Spray foam seals the underside of the roof and blocks this ventilation, trapping moisture against the timbers.
Over time this can lead to:
- Rotten rafters
- Damp
- Mould growth
- Weakened structural timbers
2. It hides defects
Once foam is applied, it becomes almost impossible to inspect the underside of the roof properly. Slipped tiles, damaged battens, and small leaks all get hidden — until they become much bigger problems.
3. Mortgage lenders and surveyors don't like it
This is often the first time homeowners find out spray foam is an issue. Many major UK mortgage lenders now refuse to lend on properties with spray foam applied to the roof. Surveyors typically flag it as a defect.
That can make selling or remortgaging your home very difficult.
4. It's expensive to remove
Because it bonds directly to the timbers, spray foam can be difficult and time-consuming to remove — especially closed-cell foam. Removal should always be done carefully to avoid damaging the roof structure.
What to do if you have spray foam
If you've discovered spray foam in your loft, the best first step is to have it inspected by a professional roofer. A proper assessment will tell you:
- The type and extent of the foam
- The condition of the underlying timbers
- Whether ventilation has been compromised
- What removal and remedial work would involve
How we can help
At Total Roofing Care we carry out spray foam removal across Berkshire, taking care to protect the underlying roof structure. After removal we inspect the timbers and roof condition and give you a clear report on what — if anything — needs doing next.
If you're worried about spray foam in your loft, get in touch for a free assessment. We'll give you honest advice about your options.