Installer ceased trading
Installer gone, eaves foamed shut: 6 of 20 readings at or above 20% in summer
near Preston · Recent inspection · Spray Foam Inspection
The house
Detached 1920s bungalow, tiled with a chimney, rooms partly in the roof slope, soffit vents on both elevations. Roof area about 81 m² including the gables.
The foam
Open-cell foam sprayed in 2022 onto cardboard rafter sliders about ½ in below a non-woven membrane, and straight onto brickwork at the gable and chimney. From nothing to about 5 in thick, with a 14 × ~4 in ridge void.
The paperwork
Order form, terms, warranty and leaflets only: no pre-installation survey, condensation-risk assessment, product approval, product name or receipts. The thickness field was blank, the terms named a different foam from the order, and an advertised insurance-backed warranty was not in the pack.
Why they called
An independent check of the loft and foam, with no buyer or other institution attached. The installer had since been dissolved, so its 30-year warranty could not be called on.
What was measured
- 20 timber readings: 6 at or above 20%, 11 at 16–19.9%, 3 below 16%; highest 24.6% at the ridge board.
- Loft air 22.5–29.1 °C, dew points 16.4–19.0 °C.
- Two uncovered downlighter lamp bodies at 132.5 °C and 134.8 °C (infrared, indicative), and cables oversprayed in several places.
What it means
Six readings at 20% or more in summer, when a loft is normally at its least damp, decided this job. They clustered at the ridge, furthest from any air: the soffit vents are there, but foam fills the eaves behind them. No evidence of rain ingress was found; the pattern fits moisture building behind sealed eaves, in the report's view a ventilation problem with a proportionate fix.
What happened next
First, an electrician to hood, cover or replace the downlighters, whatever happens to the foam. Then reopen the eaves to the soffit vents or add tile vents, make sure the extract duct ends outside, and re-read the ridge in winter. Nothing observed indicated removal as a necessary first response.
For other homeowners
If downlighters sit below sprayed foam, look at them from the loft. Two here measured above 130 °C, uncovered, in a void with quilt and with foam its own paperwork calls combustible, and that came before any insulation decision.
Read the guide: Spray foam installer gone bust? Warranties, insurance-backed cover and TrustMark · Making a complaint or claim about spray foam: step by step
The honest limit
One summer visit, with no foam cut. Most rafter surfaces are encapsulated and could not be assessed; no wall plate was exposed, the membrane's vapour permeability was not established, and the extract duct's end was not visible.