Loft boarding done properly — why raised boarding beats squashed insulation

The most common mistake we see in West Yorkshire lofts? Insulation squashed flat under chipboard sheets nailed straight to the joists. Here's why raised loft boarding is worth every penny over the cheap-and-cheerful alternative.

The 100 mm joist problem

Standard loft joists are about 100 mm deep. Current Building Regs ask for 270 mm of insulation. Do the maths — board direct onto the joists and you've crushed 170 mm of the 270 mm flat. You've kept maybe 30% of the thermal performance you paid for.

How raised systems work

Loft Legs are plastic stilts that screw onto the joists and lift the boarding to 270 mm — exactly the height of your insulation. Air can circulate above the insulation, the mineral wool stays full thickness, and you get a perfectly flat, fully boarded storage deck on top.

• Loft Legs at 600 mm centres on every joist
• Tongue-and-groove moisture-resistant boards screwed (not nailed) to the legs
• Walkway or full deck — your choice
• Aluminium loft ladder and LED light fit-out available

What it costs in 2026

Raised boarding alone (insulation already in place) runs around £95/m² supplied and fitted. Combine it with a full insulation top-up and most Leeds and Wakefield homes are in the £2,800–£4,500 range for a generous storage deck plus the full 270 mm of mineral wool underneath.