UNDER RAFTER (INTERNAL)

How To Install

Under Rafter Pitched Roof Install

Apply SuperFOIL directly to the rafters from the roll. This can be done either horizontally or vertically.

When applying horizontally, we recommended starting at the bottom of the roof and working upwards, ensuring to overlap the layers at each join.
When installing the insulation vertically, we recommend starting at the high point of the rafters and rolling the product down the rafter.

Whilst fitting SuperFOIL, you should apply tension to the product whilst stapling into place. Staple through the product into the rafters at approximately 50mm-100mm intervals using the correct size staples (see chart). Once you have finished a length, simply cut to the correct size and then continue onto fixing the next layer with a minimum of a 50mm overlap. Ensure secure fixing by stapling the insulation onto the rafters where the joint crosses.

At the eaves, trim SuperFOIL around the rafters and seal to either the wall plate, or cavity wall insulation if present.

Seal all joints, tears and cuts with SuperFOIL 100mm tape, paying special attention around any penetrations through the insulation to ensure an air tight finish.

Finish your installation by fixing counter battens on top of the insulation horizontally (maximum of 600mm centres) to allow an adequate air space.  Attach your internal finish to battens, following the manufacturer’s guidelines.

Dachausbau, Wärmeschutz, Dachkammer
ProductMinimum Batten SizeStaple Size Required
SF19+38mm20mm
SF4050mm30mm
SF6063mm40mm

Ideal Products For Internal Applications

SF19+-3

SuperFOIL SF19+

  • 2.53 R VALUE

    R Value of 2.53 When used in a roof

  • 45mm THICK

    1.5m Wide by 10m Long

SF40-3

SuperFOIL SF40

  • 3.7 R VALUE

    R Value of 3.7 When used in a roof

  • 65mm THICK

    1.5m Wide by 10m Long

SF60-3

SuperFOIL SF60

  • 4.48 R VALUE

    R Value of 4.48 When used in a roof

  • 100mm THICK

    1.5m Wide by 8m Long

Choose Your Solution

Use the charts below to find the ideal combination of insulations for your project

Internal Wall - Diagram2
SuperFOIL Product Below Rafters SuperFOIL Product Above Rafters
No Additional Insulation SF19BB SF40BB
No Additional Insulation N/A 0.41U 0.26U
SF19+ 0.34U 0.26U 0.20U
SF40 0.26U 0.17U 0.14U
SF60 0.20U 0.14U 0.12U
SuperFOIL Product Mineral Wool / Glass Fibre / Sheeps Wool - 0.044W/mK
No Additional Insulation 25mm 50mm 75mm 100mm 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm
SF19+ 0.34U 0.29U 0.25U 0.23U 0.20U 0.19U 0.17U 0.16U 0.15U 0.14U 0.13U 0.12U 0.12U
SF40 0.26U 0.23U 0.20U 0.19U 0.17U 0.16U 0.15U 0.14U 0.13U 0.12U 0.12U 0.11U 0.10U
SF60 0.20U 0.19U 0.17U 0.16U 0.15U 0.14U 0.13U 0.12U 0.11U 0.11U 0.10U 0.10U 0.09U
SuperFOIL Product Mineral Wool / Glass Fibre / Sheeps Wool - 0.037W/mK
No Additional Insulation 25mm 50mm 75mm 100mm 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm
SF19+ 0.34U 0.28U 0.24U 0.22U 0.19U 0.17U 0.16U 0.15U 0.14U 0.13U 0.12U 0.11U 0.11U
SF40 0.26U 0.22U 0.20U 0.18U 0.16U 0.15U 0.14U 0.13U 0.12U 0.11U 0.11U 0.10U 0.10U
SF60 0.20U 0.19U 0.17U 0.16U 0.15U 0.14U 0.13U 0.12U 0.11U 0.11U 0.10U 0.10U 0.09U
SuperFOIL Product Mineral Wool / Glass Fibre / Sheeps Wool - 0.032W/mK
No Additional Insulation 25mm 50mm 75mm 100mm 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm
SF19+ 0.34U 0.28U 0.24U 0.21U 0.18U 0.16U 0.15U 0.14U 0.13U 0.12U 0.11U 0.10U 0.10U
SF40 0.26U 0.22U 0.19U 0.17U 0.16U 0.14U 0.13U 0.12U 0.11U 0.11U 0.10U 0.09U 0.09U
SF60 0.20U 0.18U 0.16U 0.15U 0.13U 0.12U 0.12U 0.11U 0.10U 0.10U 0.09U 0.09U 0.08U
SuperFOIL Product PIR Foam Board - 0.022W/mK
No Additional Insulation 25mm 50mm 75mm 100mm 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm
SF19+ 0.34U 0.26U 0.21U 0.18U 0.16U 0.14U 0.13U 0.12U 0.11U 0.10U 0.09U 0.09U 0.08U
SF40 0.26U 0.21U 0.18U 0.16U 0.14U 0.12U 0.11U 0.10U 0.10U 0.09U 0.08U 0.08U 0.07U
SF60 0.20U 0.17U 0.15U 0.13U 0.12U 0.11U 0.10U 0.09U 0.09U 0.08U 0.08U 0.07U 0.07U
SuperFOIL Product Phenolic Foam Board - 0.019W/mK
No Additional Insulation 25mm 50mm 75mm 100mm 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm
SF19+ 0.34U 0.25U 0.21U 0.17U 0.15U 0.13U 0.12U 0.11U 0.10U 0.09U 0.09U 0.08U 0.08U
SF40 0.26U 0.21U 0.17U 0.15U 0.13U 0.12U 0.11U 0.10U 0.09U 0.08U 0.08U 0.07U 0.07U
SF60 0.20U 0.17U 0.15U 0.13U 0.12U 0.10U 0.10U 0.09U 0.08U 0.08U 0.07U 0.07U 0.06U

FIXING DETAILS

Ridge Detail

At the ridge install the SuperFOIL along or down the rafters starting at the ridge ensuring the SuperFOIL overlaps the ridge beam.
Fix SuperFOIL to the ridge beam with staples.
Complete the first section of roof following above installation method.
When installing the opposing side of roof, start at the ridge ensuring the SuperFOIL overlaps the ridge beam and previously installed SuperFOIL by a minimum of 50mm.
Secure in place with staples and seal the joint with 100mm Superior Foil Tape.

Eaves Detail

At the eaves, trim the SuperFOIL to size, ensuring that sufficient material is left to overlap the wall plate.
For timber wall plates, staple the SuperFOIL into place, and then seal with 100mm superior foil tape to form an airtight seal.
If attaching to plaster finish, brick or block, fold back the SuperFOIL and apply a suitable sealant as a continuous 8mm bead to the folded edge of the SuperFOIL. Press into place, ensuring sufficient adhesion. Seal with 100mm superior foil tape. 

Pipes,Vents & Holes

At penetrations such as vent ducting, pipework etc, SuperFOIL should be trimmed to ensure there are no gaps around the penetration.
Using 100mm Superior Foil Tape ensure the SuperFOIL is well sealed around the penetration to create an airtight barrier. This can be achieved by using small sections of tape and working around the penetration.

Between Purlin

Attach SuperFOIL to rafters using correct method for your application , install up to the purlin and then cut the insulation, leaving enough product to fix into place on the side of the purlin.
Staple securely into place and seal the joint with SuperFOIL 100mm foil tape.
Further secure the SuperFOIL by placing a counter batten against the purlin, ensuring that the SuperFOIL is compressed tightly between the batten and purlin.

Behind Purlins

Attach SuperFOIL to rafters using correct method for your application.
At the purlin, cut the SuperFOIL to the correct length to be able to be passed underneath the purlin with a small amount of product on the opposite side.
Join the next piece of insulation, ensuring to tape the joint with SuperFOIL 100mm foil tape.
Finish the installation by installing counter battens directly on top of the SuperFOIL to the rafters.

Skylights & Dormer Windows

Install SuperFOIL using correct method for your application.
To finish installation around skylights or Dormer windows, simply trim the SuperFOIL up to the frame and staple the insulation to the surrounding framework where possible.
Finish installation by sealing all joints with SuperFOIL 100mm Superior foil tape.

UNSURE WHERE TO START?

Our FREE guide gives you all the information on saving time and money when insulating your home, and how to really make a difference to the comfort of your rooms.

Please enter your name.
Please enter a valid email address.
Please check the required field.
Something went wrong. Please check your entries and try again.
E-book-Opt-in