How to install 3 layers of SuperQuilt - Pitched Roof

Here we detail how to insulate a pitched or flat roof using 3 layers of SuperQuilt Insulation.

The displayed method will achieve a U-value of 0.15, which is a popular target U-value if you are undergoing a refurbishment or roof extension in the UK.

By using our recommended detail, you will save considerable cost and installation time compared to rigid PIR insulation. A key benefit of our triple-layer detail is that shallow-depth rafters are perfectly fine — there's no requirement to extend your rafters.

The guide below is specifically for pitched roofs. It's based on 100mm rafters, insulating purely from the inside of the loft (under rafters), and assumes a breather membrane is already fitted over the rafters.

Measure and Cut SuperQuilt

Measure the roof space to calculate how much SuperQuilt is required. We recommend rolling and installing it horizontally on the roof rafters. You can then cut the length of SuperQuilt required for your first layer.

Allow an extra 60mm per rafter for the first layer, due to the recess.

Install 1st SuperQuilt — Recessed

Start by fixing the first layer of SuperQuilt. We recommend the first layer be recessed and stapled up into the rafters by 25–30mm, stapling the multifoil on both sides of the rafters and the face of the rafters. Recessing, in a nutshell, is weaving the multifoil in and out of the rafters while maintaining the product as a continuous layer.

Ensure a 50mm overlap is applied.

Tape and Seal First Layer of SuperQuilt

Once the first recessed layer is fully stapled and fixed in place, seal up SuperQuilt using ThermaSeal Foil Joining Tape. Fully tape and seal this layer over the overlaps and around the perimeter. This ensures the product works as a high-performance vapour control layer, reducing condensation.

Install 2nd Layer of SuperQuilt — Taut

Next, install the second of the three layers of SuperQuilt. Nail this layer flat and taut as a continuous layer under the rafters.

We recommend nailing this layer, as stapling will be difficult once a layer of SuperQuilt is already wrapped around each rafter.

Tape and Seal 2nd Layer of SuperQuilt

Fully tape and seal SuperQuilt using ThermaSeal Foil Joining Tape, ensuring it is sealed over the overlaps and around the perimeter.

Fix 1st Set of Battens

Screw battens over the top of the second layer of SuperQuilt at 400mm centres.

We recommend either 38mm or 50mm depth battens — check your bespoke PDF U-value calculation for clarity.

Install 3rd Layer of SuperQuilt — Taut

Staple the third and final layer of SuperQuilt as a flat, taut, continuous layer using 14mm staples.

Tape and Seal 3rd Layer of SuperQuilt

Fully tape and seal SuperQuilt using ThermaSeal Foil Joining Tape, ensuring it is sealed over the overlaps and around the perimeter.

Screw Final Set of Battens

Screw the second and final set of battens over the top of the third layer of SuperQuilt at 400mm centres.

We recommend 25mm deep battens for this section.

Finish with Plasterboard

Screw 12.5mm standard plasterboard over the final battens, and skim.

Any questions at all, just get in touch here. You can either submit an enquiry or request a call-me-back — we are more than happy to assist you.

Disclaimer – Ecohome Insulation cannot be held responsible for any losses financially or physically from advice provided in this How-To-Guide.