Superfoil Insulation | Insulation

Embarking on a journey toward optimal thermal performance involves delving into the expansive world of Superfoil Insulation. With an impeccable lineup of insulative materials offered on insulation4less, Superfoil offers a comprehensive suite of solutions tailored to diverse insulation needs, adhering to both residential and commercial specifications.

What is Superfoil Insulation?

Superfoil insulation is a high‑performance multi‑foil insulation solution designed to provide exceptional thermal efficiency, moisture control, and fire resistance—all in a lightweight, thin roll. Manufactured with multiple layers of reflective foil, foam, and wadding, Superfoil works by reflecting radiant heat, trapping air, and reducing heat transfer. It’s ideal for new builds, renovations, and retrofit projects where space is limited but performance is essential.

Reflective Foil Insulation

General and Specific Use Foil

Products such as SuperFOIL SFTV 1L, SuperFOIL SFBA MP, and SuperFOIL SFBA BB fall into this category, offering a multi-layered insulating foil that is adept at providing optimal thermal resistance in roofs, walls, and floors. These products are especially useful in settings where the maximisation of space is paramount, given their thin profile and exceptional thermal performance.

Radiator Reflectors

Reflecting on the efficient use of energy, Superfoil Rad Wrap is tailored to augment the efficiency of radiators by reflecting the heat typically lost into the wall back into the room. Ideal for DIY and professional applications alike, Rad Wrap is an exemplary choice for enhancing the thermal efficiency of existing heating systems without invasive interventions.

Tape and Accessories

Navigating through the versatile range of foils, the SuperFOIL Superior Foil Tape and SuperFOIL Standard Foil Tape are indispensable companions in ensuring the seams between insulation sheets are sealed meticulously, mitigating thermal bridging and providing a continuous insulation layer.

Advanced Multi-Purpose Insulation

Diving deeper into the multifaceted Superfoil lineup, products such as SuperFOIL SF19 Plus, SuperFOIL SF40, and SuperFOIL SF60FR cater to the advanced insulation requirements of varied applications, providing multi-layer insulation for roofs, walls, and floors across an array of structural forms and conditions.

Fire-Rated Solutions

For scenarios where fire-resistance is pivotal, offerings like Superfoil SF19FR and SuperFOIL SF40FR provide enhanced thermal insulation whilst adhering to rigorous fire safety standards. These products marry thermal performance with fire safety, ensuring that your structure is not only thermally efficient but also adherent to safety protocols.

Pipe and Cavity Insulation

To shield pipes from the cold and prevent heat loss, Superfoil Pipe Wrap offers a pragmatic solution. Likewise, SuperCLOSE XPS Insulated Cavity Closer provides a practical solution for closing the cavities around windows and doors, averting thermal bridges and enhancing the overall energy efficiency of buildings.

SuperFOIL range guide

SuperFOIL covers more than one type of foil product. The range includes thicker multifoil insulation for roofs, walls and floors, thinner reflective membranes and wraps, products for suspended floors and underfloor heating, breathable variants, tapes and small-job products such as radiator and pipe wraps. The right choice therefore starts with the construction, not simply the thickest roll.

The main SF19+, SF40 and SF60 products are 3-in-1 multifoils: insulation, a radiant barrier and a vapour control layer when installed as specified. Their declared thermal performance must be read carefully. A core R-value is the resistance of the product itself. Higher application R-values include specified adjacent air spaces. A U-value belongs to the complete roof, wall or floor build-up, so it should not be quoted for one roll in isolation.

SF19+, SF40 or SF60: which one do I need?

Choose SF19+ when keeping the build-up slim is a priority or when the multifoil will work with another insulation layer. Choose SF40 when you have more depth and want a stronger thermal contribution from the multifoil itself. Choose SF60 where the available depth can accommodate 100mm and the design calls for the highest core thermal resistance in this comparison.

Does SuperFOIL need an air gap?

Yes, an adjacent air space is important when you want the reflective faces to contribute their designed radiant-barrier performance. SuperFOIL states that air spaces increase the thermal performance of its reflective products. Its current guidance gives minimum air-space depths of 13mm for roof heat flow, 20mm for wall heat flow and 50mm for downward floor heat flow. These are application figures, not a universal instruction to leave the same gap everywhere.

The air space used for reflective performance should be an unventilated space. A ventilated roof void is a different part of the construction. The correct arrangement depends on whether the roof is warm or cold, the membrane position and the moisture design. SuperFOIL also identifies SFUF as an exception: its thermal performance is not dependent on an air gap in the same way.

How to install multifoil without losing performance

Keep the multifoil continuous across the face of the timbers rather than cutting it into narrow strips between every rafter. SuperFOIL's own FAQ recommends a continuous layer because it maintains the designed insulation and vapour-control function. Joints, laps and penetrations must then be sealed with the specified foil tape so that the layer remains continuous.

For suspended timber floors, the manufacturer's current installation guide shows adjacent rolls overlapped by around 100mm and sealed with SuperFOIL MultiFOIL tape. It also shows the product fixed with SuperFOIL spacers or with staples and/or battens, followed by the floorboards. Other roof and wall details differ, so use the installation drawing for the actual product and construction rather than carrying one floor detail across every job.

Fire, water and vapour performance

These are product declarations, not fire-resistance periods for a complete wall or roof. Fire resistance of a construction depends on the tested or classified system, including linings, framing, fixings and insulation. Where a project has a specific fire requirement, use the relevant system evidence rather than treating a Euroclass for the insulation roll as a complete assembly rating.

Benefits of Superfoil Insulation

• Excellent Thermal Performance – Achieves impressive R‑values in minimal thickness, helping reduce heating and cooling costs.
• Built‑In Vapour Control – Prevents condensation and moisture build‑up for a healthier building environment.
• Fire Safety Options – Available in fire‑rated versions (e.g., SF19FR, SF60FR) for added protection.
• Lightweight & Flexible – Easy to handle, cut, and fit, even in tight spaces.
• Durable & Long‑Lasting – Resistant to tearing, water penetration, and general wear over time.
• Multi‑Functional – Acts as an insulation layer, radiant barrier, and vapour check in one product.

Applications of Superfoil Insulation

• Pitched Roofs & Loft Conversions – Improve thermal efficiency without reducing headroom.
• Timber Frame & Stud Walls – Combine insulation with vapour control in one step.
• Floors & Ceilings – Boost insulation without major height adjustments.
• Garden Rooms, Sheds & Garages – Quick and effective insulation for outbuildings.
• Extensions & Retrofits – Ideal for upgrading insulation where space is restricted.

Frequently asked questions

How good is SuperFOIL insulation?

SuperFOIL's main multifoils provide declared core thermal resistance from 1.63 m²K/W for SF19+ to 3.58 m²K/W for SF60. Their reflective faces can add performance when installed with the specified air spaces. The useful measure is the calculated performance of the complete roof, wall or floor build-up, not a marketing claim for one layer.

What is the difference between SF19+, SF40 and SF60?

SF19+ is 45mm thick with a core R-value of 1.63 m²K/W. SF40 is 65mm with 2.66 m²K/W. SF60 is 100mm with 3.58 m²K/W. The thicker products provide greater core resistance, but available depth, the complete U-value calculation and the construction detail should decide the specification.

Can SuperFOIL be used on its own?

SF19+, SF40 and SF60 can be used as standalone insulation in suitable calculated constructions, or combined with other insulation in a hybrid build-up. Compliance is determined by the complete element. Check the target U-value, air spaces, moisture design and the manufacturer's detail before treating one roll as a complete insulation solution.

Can SuperFOIL be used with PIR insulation?

Yes. SuperFOIL can be used in hybrid constructions with conventional insulation such as PIR where the design calls for it. This can combine a rigid insulation layer with a continuous multifoil and vapour-control layer. The thicknesses should come from a complete U-value and condensation assessment rather than simply adding headline R-values together.

Can SuperFOIL be used in a loft or pitched roof?

Yes. SF19+, SF40 and SF60 are manufacturer-listed for roof applications. The correct detail depends on the roof construction, ventilation strategy and whether other insulation is present. SuperFOIL advises installing the multifoil continuously across the face of timbers rather than cutting it into strips between rafters, then sealing joints and penetrations.

Does SuperFOIL act as a vapour control layer?

The main SuperFOIL multifoil products are designed as 3-in-1 products combining insulation, a radiant barrier and vapour control. The vapour-control function relies on continuity. Laps, edges and service penetrations therefore need appropriate sealing. Moisture design should still be checked for the complete construction, particularly in roof and internal-wall retrofit work.

How much SuperFOIL do I need?

Calculate the area to be insulated in square metres, then divide by the usable coverage of the selected roll and round up to whole rolls. SF40 covers 15m² per 10m × 1.5m roll, while SF60 covers 12m² per 8m × 1.5m roll. Allow separately for the laps required by the installation detail.

What tape should be used with SuperFOIL?

Use a compatible SuperFOIL foil tape specified for sealing the relevant product's laps, joints and penetrations. The live collection includes Standard Foil Tape and Superior Foil Tape. Correct sealing matters because the multifoil layer is intended to remain continuous for airtightness and vapour control as well as thermal performance.

Can SuperFOIL be cut to fit?

SuperFOIL is a flexible roll product and can be cut for detailing, but the main multifoil should normally remain a continuous layer across the face of the framing. The manufacturer specifically advises against cutting it into strips between rafters. Seal cut edges, laps and penetrations in accordance with the installation detail for the selected product.

What fire rating does SuperFOIL have?

Fire classification varies by product. Current manufacturer technical information lists SF19+ as Euroclass F and SF40 and SF60 as Euroclass E. These classifications apply to the products and are not a fire-resistance period for a complete wall, floor or roof. Use tested or classified system evidence where the project has a fire requirement.