Solutions: Multi Foil & Reflective Membranes - Walls
| L1A 2010 | CFSH – Level 4 | Low Carbon / PassivHaus |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Stud | U Values
External Wall Solutions Fully filled cavity unless otherwise specified |
0.30
to 0.23 |
0.22 | 0.21 | 0.20 | 0.19 | 0.18 | 0.17 | 0.16 | 0.15 | 0.14 | 0.13 | 0.12
to 0.10 |
||
| Outer (Breathable) |
Lambda Insulation
Between |
Inside
(AVCL) |
Click Icon below to download U value calculation | ||||||||||||
| 89mm | PHOTONFRAME A1 Fire Rated |
0.040 Glass | PHOTONCHECK A1 Fire Rated |
 |
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| 0.035 Glass | |
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| 0.032 Glass | |
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| PHOTONWRAP A1 Fire Rated |
0.040 Glass | PHOTONFOIL A1 Fire Rated |
|
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| 0.035 Glass | |
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| 0.032 Glass | |
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| 140mm | PHOTONFRAME A1 Fire Rated |
0.040 Glass | PHOTONCHECK A1 Fire Rated |
|
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| 0.035 Glass | |
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| 0.032 Glass | |
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| PHOTONWRAP A1 Fire Rated |
0.040 Glass | PHOTONFOIL A1 Fire Rated |
|
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| 0.035 Glass | |
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| 0.032 Glass | |
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| 0.022 PIR
Part filled |
|
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| PHOTONFRAME A1 Fire Rated |
0.040 Glass | |
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| 0.035 Glass | |
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| 0.032 Glass | |
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| PHOTONAIR | 0.035 Glass | P/BOARD | |
Contact us for PhotonAir Solutions | |||||||||||
| 184mm | PHOTONFRAME A1 Fire Rated |
0.040 Glass | PHOTONCHECK A1 Fire Rated |
|
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| 0.035 Glass | |
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| 0.032 Glass | |
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| PHOTONWRAP A1 Fire Rated |
0.040 Glass | PHOTONFOIL A1 Fire Rated |
|
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| 0.035 Glass | |
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| 0.032 Glass | |
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| PHOTONFRAME A1 Fire Rated |
0.040 Glass | |
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| 0.035 Glass | |
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| 0.032 Glass | |
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| U Value | 0.30
to 0.23 |
0.22 | 0.21 | 0.20 | 0.19 | 0.18 | 0.17 | 0.16 | 0.15 | 0.14 | 0.13 | 0.12 to 0.10 |
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What is Multi Foil Insulation?
Multi foil insulation is a high performance, reflective insulation solution made up of multiple layers of aluminium foil and insulating core materials designed to reduce heat transfer through radiation, conduction, and convection. Products such as PhotonFoil A1 are engineered for use across a range of applications, including loft conversions, timber frame walls, and re roofing projects, making them suitable for both residential and commercial buildings.
With advanced constructions that incorporate woven glass, aluminium low emissivity outer layers, and high density insulation cores, modern multi foil systems are designed to deliver durability, thermal efficiency, and long term performance.
Multi Foil Insulation for Timber Frame Walls
For timber frame walls, multi foil insulation can be installed across the warm side or the cold side of the studwork to enhance overall thermal performance while maintaining a slim wall build up. Solutions such as PhotonFrame A1 are specifically developed for cold side timber frame applications, and PhotonFoil-A1 for warm side installation supporting effective moisture management alongside improved insulation.
Reflective breather membranes like PhotonWrap A1 and vapour control layers such as PhotonCheck A1 can also form part of a complete wall system, helping to control air leakage and vapour movement while contributing to the wall’s overall efficiency. This layered approach ensures compatibility with modern timber frame construction methods.
Benefits of Multi Foil Insulation
One of the key advantages of advanced multi foil insulation products is their A1 non combustible classification to BS EN13501-1, placing them in the same fire performance category as stone wool, glass wool, concrete, and brick. This provides confidence for designers, builders and building control, particularly where fire safety requirements are stringent.
In addition to enhanced fire performance, multi foil systems can act as effective vapour and air leakage barriers when correctly installed, helping to reduce draughts, improve airtightness and support lower energy consumption. Lightweight, flexible, and easy to manage, they offer a versatile, high performance solution for new build and refurbishment timber frame wall projects.