Shopping list for insulating a 6 × 4 m loft

How this example was made

It was worked out when this page was built, by the same room planner and formulas as the editable list. The room figures are round examples. Product coverage, pack and allowance figures are the planner’s labelled generic examples, not figures for a product.

AI tools drafted the page and automated tests compare its list with the planner. It has not been checked by a tradesperson or anyone outside the build. No price is shown or used.

The room and assumptions

Room: 6 m × 4 m. Work: loft insulation.

One rectangular room, 6 m × 4 m, measured in metres.
Doors and windows are not used for a loft floor quantity.
Loft insulation: 1 new layer of 170 mm mineral-wool roll over one rectangular horizontal cold-loft floor. This is a material quantity, not a thermal or installation design.
Every quantity is rounded once, at the end, up to whole packs. Working uses unrounded figures.
Mineral-wool loft insulation rolls use generic example figures, not the figures of any product. Enter the depth and pack coverage from the chosen roll for a closer answer.

The shopping list

2 lines marked Need and 6 marked Check first. Lines that this job does not need are left out here; the full planner shows them too.

Need

Mineral-wool loft insulation rolls
Need
4 × 8.01 m² roll or pack (32.04 m²)
Why, and what to check
24 m² of loft floor × 1 layer, plus 5% for cuts and fitting, in rolls or packs covering 8.01 m² each.
Check: This reaches 270 mm from 100 mm using 1 × 170 mm layer. Check the chosen build-up, joist spacing and roll width before buying.
Working: 24 m² × 1 layer = 24 m²; plus 5% = 25.2 m². 25.2 m² ÷ 8.01 m² = 3.15, so 4 whole rolls or packs.
Gloves, eye protection, covered skin and suitable respiratory protection
Need
Why?
Mineral-wool fibres and loft dust can irritate skin, eyes and breathing.

Check first

Eaves ventilation guards
Check first
Why, and what to check
Loft ventilation must stay open when insulation reaches the eaves.
Check: Check whether guards are needed from the roof ventilation and product instructions. Do not block eaves vents with insulation.
Loft hatch insulation and draught seal
Check first
Why, and what to check
The hatch interrupts the insulated loft floor.
Check: Measure the hatch and choose a safe detail that still lets it open and close.
Pipe and cold-water tank insulation
Check first
Why, and what to check
The loft becomes colder after the floor is insulated.
Check: Check every pipe and tank. Follow current guidance; do not insulate beneath a cold-water tank without a suitable design.
Downlight covers where the checked design needs them
Check first
Why, and what to check
Insulation can trap heat around electrical equipment.
Check: Have the wiring and lights checked where needed. Follow the equipment and insulation instructions; do not cover something that must dissipate heat.
Raised loft walkway or boarding system
Check first
Why, and what to check
Boards laid directly on deep insulation compress it and can hide the joists.
Check: If the loft is used, plan safe access and storage with a system suited to the joists and intended load. This calculator does not design it.
Tape measure, insulation knife and safe loft access
Check first
Why, and what to check
For measuring depth and gaps, cutting rolls and moving safely above the ceiling.
Check: Only stand or kneel on secure supports. Stop if access, wiring, damp, vermin, fragile materials or an unknown older material makes the loft unsafe.

Before you use it

Measure only the floor area that will be insulated.
Use the roll coverage, layer build-up and fitting instructions for the chosen system.
Check ventilation, electrics, downlights, pipes, tanks, the loft hatch and safe access before work starts.

Built and checked with AI tools, not yet by a tradesperson or anyone outside the build. Estimates are arithmetic on your measurements and the figures shown with them: follow each product's own instructions.

All example shopping lists · How the estimates are worked out