Open-cell vs closed-cell spray foam — what's the difference?
Your removal quote depends heavily on which foam is in your loft. Open-cell takes less time and costs less to remove. Closed-cell takes longer, demands more skill, and runs 30-40% more expensive per square metre. Here's how to tell which you've got — and why.
The 60-second test
Press a fingernail into the foam. If it dents easily and springs back, it's open-cell. If it's hard and your nail barely marks it, it's closed-cell. Open-cell looks lighter and can have a slightly fluffy texture. Closed-cell is denser, often yellow or off-white, and feels rigid like dense polystyrene.
Why open-cell costs less to remove
Open-cell foam is approximately 0.5 lb/cu ft density — soft, flexible, easy to pull and cut. Two operatives can typically strip a 3-bed semi loft in two days, working steadily through the rafter bays.
Closed-cell foam is around 2 lb/cu ft — four times denser. It bonds firmly to roof felt and timber. Cutting it back demands sharper tools, more time, and more care to leave the underlying timbers undamaged. The same 3-bed semi takes 3-4 days for closed-cell. Disposal volume is similar but the labour cost difference is significant.
Mortgage implications — does the type matter?
Practically no. Major UK lenders (Halifax, TSB, Nationwide, Skipton, Leeds BS, Barclays, NatWest, Santander, HSBC) refuse properties with spray foam regardless of cell type. The IMA and PCA position aligns with this: any retrofit spray foam in the roof void is a problem until it's been removed and the timbers verified.
There are some narrow exceptions for foam installed to BBA standards with full IMA documentation, but most installations under the ECO4 grant programme don't meet that bar. Removal is the safest path back to a mortgageable property.
What if I don't know which I have?
Don't worry about identifying it yourself. Any legitimate surveyor will tell you on the spot at the free survey. We're set up to handle either type — the only difference is the price band on the quote.
The cost ranges in 2026
Open-cell removal across West Yorkshire runs £50-60 per square metre of foam coverage. Closed-cell £65-80 per m². Coverage is measured on the actual sprayed area, which for a typical 3-bed semi loft works out to 70-90 m² depending on roof shape.
We always include disposal, paperwork pack and 12-month guarantee in the bundled price. RICS sign-off and replacement insulation are quoted separately if you need them.
Call 07375 937930.
Free survey within forty-eight hours across West Yorkshire.