---
title: "How many rolls of loft insulation? Table by size (UK)"
description: "Loft insulation for 10 loft sizes, 3 × 4 m to 5 × 10 m. A 4 × 6 m loft floor needs 4 rolls or packs of 8.01 m² for one new layer. Generic example figures."
url: https://buildbatch.co.uk/examples/how-many-rolls-of-loft-insulation-by-loft-size/
---

[Guides](https://buildbatch.co.uk/guides/) / [Example shopping lists](https://buildbatch.co.uk/examples/)

# How many rolls of loft insulation do I need? A table by loft size

A 4 × 6 m loft floor (13.1 × 19.7 ft) is 24 m² and needs 25.2 m² of insulation for one new layer of 170 mm mineral wool with 5% extra: 4 rolls or packs of 8.01 m² each (32.04 m²). The depth, the allowance and the pack coverage are generic example figures, not a product’s and not an insulation design: use the depth and coverage printed on the roll you choose.

Worked out by the planner · Updated 2 October 2026

**Rolls of loft insulation by loft size**

| Loft floor | In feet | Loft floor area | With 5% extra | Rolls or packs to buy | Left over | Your loft floor |
| --- | --- | --- | --- | --- | --- | --- |
| 3 × 4 m | 9.8 × 13.1 ft | 12 m² | 12.6 m² | 2 rolls or packs of 8.01 m² each (16.02 m²) | 3.42 m² | [Open 3 × 4 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=4&width=3&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 3 × 5 m | 9.8 × 16.4 ft | 15 m² | 15.75 m² | 2 rolls or packs of 8.01 m² each (16.02 m²) | 0.27 m² | [Open 3 × 5 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=5&width=3&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 4 × 5 m | 13.1 × 16.4 ft | 20 m² | 21 m² | 3 rolls or packs of 8.01 m² each (24.03 m²) | 3.03 m² | [Open 4 × 5 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=5&width=4&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 4 × 6 m | 13.1 × 19.7 ft | 24 m² | 25.2 m² | 4 rolls or packs of 8.01 m² each (32.04 m²) | 6.84 m² | [Open 4 × 6 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=6&width=4&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 4 × 7 m | 13.1 × 23.0 ft | 28 m² | 29.4 m² | 4 rolls or packs of 8.01 m² each (32.04 m²) | 2.64 m² | [Open 4 × 7 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=7&width=4&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 5 × 6 m | 16.4 × 19.7 ft | 30 m² | 31.5 m² | 4 rolls or packs of 8.01 m² each (32.04 m²) | 0.54 m² | [Open 5 × 6 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=6&width=5&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 5 × 7 m | 16.4 × 23.0 ft | 35 m² | 36.75 m² | 5 rolls or packs of 8.01 m² each (40.05 m²) | 3.3 m² | [Open 5 × 7 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=7&width=5&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 5 × 8 m | 16.4 × 26.2 ft | 40 m² | 42 m² | 6 rolls or packs of 8.01 m² each (48.06 m²) | 6.06 m² | [Open 5 × 8 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=8&width=5&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 5 × 9 m | 16.4 × 29.5 ft | 45 m² | 47.25 m² | 6 rolls or packs of 8.01 m² each (48.06 m²) | 0.81 m² | [Open 5 × 9 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=9&width=5&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |
| 5 × 10 m | 16.4 × 32.8 ft | 50 m² | 52.5 m² | 7 rolls or packs of 8.01 m² each (56.07 m²) | 3.57 m² | [Open 5 × 10 m in the planner](https://buildbatch.co.uk/start/#v=1&job=loft&walls=none&ceiling=none&trim=none&units=m&length=10&width=5&surface=sound&subfloor=unsure&ground=unsure&fitting=unsure&loft=quick&end=13) |

Each row is the planner’s answer for that loft floor, worked out when this page was built. The link at the end of a row opens the planner with that loft floor filled in, to change the measurements and the product figures.

The table counts rolls for one new layer. It is a quantity, not a design for insulation depth, ventilation, electrics or safe access. A loft that needs more than one new layer takes the floor area times the layers: the [loft insulation calculator](https://buildbatch.co.uk/loft-insulation-calculator/) takes the depths you enter, and [How much loft insulation do I need?](https://buildbatch.co.uk/guides/how-much-loft-insulation-do-i-need/) shows the sum.

The square metres in a roll or pack differ from one product to the next, so the count changes with the roll you choose. The area with the allowance does not: divide it by the square metres printed on your roll or pack and round up.

## What the table assumes

Each loft floor is a rectangle.

- 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.

## How this table was made

It was worked out when this page was built, by the same room planner and formulas as the editable list: each row is one room sent through the planner. The room sizes 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 every cell with the planner. It has not been checked by a tradesperson or anyone outside the build. No price is shown or used.

## Before you use it

Measure only the floor area of your own loft that will be insulated. Check the figures against the room, and follow each product's own instructions: they decide coverage, coats and preparation.

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.

**Make it your room.** The planner works from your own measurements and the figures on your tin, roll or pack, and gives the whole shopping list with its working.

[Loft insulation calculator: your loft and your roll](https://buildbatch.co.uk/loft-insulation-calculator/)

- [Guide: how much loft insulation do I need?](https://buildbatch.co.uk/guides/how-much-loft-insulation-do-i-need/)
- [The whole shopping list for a 4 × 6 m loft floor](https://buildbatch.co.uk/examples/insulating-a-6-by-4-m-loft/)

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