Loft Insulation Case Study — 120m² Loft Insulation Top-Up Before a Sale, Winchester

The problem

The loft insulation had been picked up in a survey while the sale of the property was going through, which is one of the more common ways people end up calling us. Nothing was wrong with the roof — the insulation simply was not doing its job any more.

A bungalow makes that more significant than it sounds. The whole footprint of the house sits under the loft, so at roughly 120m² this was a far larger heat-loss surface than a two-storey house of the same size would have.

The wool that was there had settled and thinned over the years, and in places it had been pulled back or disturbed, leaving bare stretches between the joists.

The other constraint was time. A sale was in progress, so the work needed doing quickly rather than being scheduled in several weeks out.

Our assessment

The existing wool was sound enough to keep, so there was no case for stripping the loft out. It needed redistributing and topping up rather than replacing.

We recommended evening out what was already down, then cross-laying a new layer over the joists across the full 120m² so the whole loft came up to one consistent depth rather than being patched in the worst areas.

We also booked it in for that week, so the survey point could be signed off without the sale waiting on us.

The installation

The team started by redistributing the existing wool, pulling it back into the bays it had come away from and levelling out the depth across the loft.

A new layer was then cross-laid over the top of the joists across the whole 120m², rather than only between them, so the timber itself is covered and the cold bridges through the joists are reduced.

The trussed roof meant a lot of bracing to work around, and a bungalow loft of that size means a long way to carry material from the hatch, so the sequencing mattered more than the technique.

The eaves were kept clear throughout so the airflow path into the roof was not blocked by the new layer.

The result

The full 120m² loft now has continuous, even insulation rather than settled patches, with the joists covered by the cross-laid layer.

The point raised in the survey was dealt with, and because the work was completed within the week of the survey the sale was not held up waiting on it.

For the buyer it means taking on a bungalow whose largest heat-loss surface has just been brought up to standard.