How to measure your roof accurately, ready to insulate with Multifoil Insulation products.

This blog will show you how to measure your….

  • Pitched Roof / Rafters
  • Loft Floor Joists
  • Gable End
  • Rafter Centres

Measuring your Pitched Roof / Rafters

The simplest way to measure a pitched roof is to….

  1. Measure the length and the height (Eaves to Ridge) of the internal loft space.
  2. Then Multiply these figures together.
  3. If your home has two sloping roof sections, then multiply this by two.

Example – If the length is 8m, and height is 4.3m:
8m x 4.3m = 34.4m²
34.4m² x 2 = 68.8m²
Total m² = 68.8m²

Below is a list of insulation materials for pitched roof/ rafter level insulation applications:

SuperQuilt Multifoil Insulation
EcoQuilt Expert Multifoil Insulation
BreatherQuilt Multifoil Insulation (From External)

Measuring your Loft Floor Joists

The most effective way to measure a loft floor is to take the length of the loft space, then multiply this by the width to calculate the area.

Example – The length of loft is 6.2m, and the width is 4m.
6.2m x 4m = 24.8m²

We supply a ready made Loft Floor Kit, perfect for insulating loft floor joists. This exclusive loft floor kit contains EcoQuilt Expert insulation, alongside fitting items such as Thermaseal Foil Joining tape, a Staple Gun, Staples & Next Day Delivery. This kit is the perfect solution that avoids using Mineral Wool.

Measuring you Gable End

The simplest way to measure a Gable End is to…

  1. Measure the width along the loft floor.
  2. Then measure the height of the wall, from the loft floor to the ridge.
  3. Multiply these measurements together, and finally divide by two.

Example – Loft floor width is 3.5m, and height is 4m.
3.5m x 4m = 14m²
14m² divide by 2 = 7m²

Below is a list of insulation materials suitable for insulating Gable End Walls;

SuperQuilt Multifoil Insulation
EcoQuilt Expert Multifoil Insulation

*Next Working Day Delivery applies to mainland UK orders over £100 (Ex VAT) Orders also must be placed before 2pm. Weekend orders are delivered Tuesday.

Measuring your Rafter Centres


The most effective way to measure the centres of your rafters. Firstly measure the left side of one rafter, to the left side of the next rafter along and repeat this for how many rafters you have. Commonly rafter centres are between 400mm & 600mm. This method can also be used for measuring Stud Walls & Loft Joists.

Do you have a project going through building control? Visit our free to use Online U-value Calculator. Instant results on the most cost-effective solution!

Or if you require any assistance on calculating specific U-values, please call our Tech Team on 0114 323 0045.

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