What is internal wall insulation?

Internal wall insulation is the material used to add a thermal layer to solid-walled homes. It is especially useful for older solid wall houses and is commonly available as PIR boards, EPS panels, and mineral wool.

How much does internal wall insulation cost?

The total cost depends on material choice and project size. Prices are usually calculated per square metre for both boards and rolls. They can start as low as £2-£3 and climb to £49 or more per m². These prices typically refer to supply only; installation costs are additional.

How thick should internal wall insulation be?

Thickness varies depending on the material and available space. Thicker insulation provides better thermal resistance, but consider whether you have enough space for it. For optimal performance, a thickness range of 50 - 100mm applies to PIR boards. EPS boards require 75 - 100mm, while mineral wool slabs and rolls require 100 - 150mm. Consider getting a recommendation for optimal insulation thickness from a qualified installer. Thicker insulation improves U-values by reducing heat loss through the wall.

How to fit internal wall insulation?

You can fit insulation on interior walls using two methods. In both, the walls should be clean and dry before adding the insulant. Direct Fix: This is where you attach the boards directly to the wall and add a finish of your liking. Batten and Frame: Here, you fix timber or metal studs to the wall, insert the insulation slab or roll, then cover with plasterboard. Improper installation can lead to interstitial condensation; always use a vapour control layer where required. If unsure of doing a perfect installation, consult a qualified installer to avoid condensation or cold bridging issues.

Internal Wall Insulation Acoustic

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60mm Rockwool Flexi Slab Acoustic Insulation 1200mm x 600mm 103.68m2 Pallet

60mm Rockwool Flexi has been designed as a multi-use, dual-purpose acoustic and thermal mineral wool insulation with a unique flexible edge along one side. It is suitable for use all over the home, in pitched roof rafters, framed external walls, internal partitions, intermediate floors, separating walls and floors, and timber suspended ground floors.

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60mm Rockwool RWA45 Acoustic Insulation Slab 1200 x 600mm 92.16m2 Pallet

60mm Rockwool RWA45 has been developed for thermal, acoustic and fire performance in a range of construction types. It is suitable for applications on partition walls, ceilings, floors and roofs.

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70mm Rockwool Flexi Slab Acoustic Insulation 1200mm x 600mm 92.16m2 Pallet

70mm Rockwool Flexi has been designed as a multi-use, dual-purpose acoustic and thermal mineral wool insulation with a unique flexible edge along one side. It is suitable for use all over the home, in pitched roof rafters, framed external walls, internal partitions, intermediate floors, separating walls and floors, and timber suspended ground floors.

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75mm Knauf Rocksilk RS45 Building Insulation Slab 1200mm x 600mm 4.32m2 Pack

75mm Knauf Insulation Rocksilk RS45 is a Rock Mineral Wool slab, designed for use in multiple thermal and acoustic applications. It is non-combustible with the best possible Euroclass A1 reaction to fire classification.

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90mm Rockwool Flexi Slab Acoustic Insulation 1200mm x 600mm 86.40m2 Pallet

90mm Rockwool Flexi has been designed as a multi-use, dual-purpose acoustic and thermal mineral wool insulation with a unique flexible edge along one side. It is suitable for use all over the home, in pitched roof rafters, framed external walls, internal partitions, intermediate floors, separating walls and floors, and timber suspended ground floors.

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60mm Superglass Multi Acoustic Roll Insulation 13.50m2 Roll

60mm Superglass Acoustic Partition Roll (APR) is a lightweight, non-combustible glass mineral wool insulation roll. It is suitable for the following applications: internal walls and floors, timber and metal stud partitions, drylining systems and separating walls and floors. Manufactured at a minimum density of 10kg/m³.

£29.41£35.29 Ex VATInc VAT
£2.18£2.62 Per m2 Get restock alert
80mm Superglass Multi Acoustic Roll Insulation 12.48m2 Roll

80mm Superglass Acoustic Partition Roll (APR) is a lightweight, non-combustible glass mineral wool insulation roll. It is suitable for the following applications: internal walls and floors, timber and metal stud partitions, drylining systems and separating walls and floors. Manufactured at a minimum density of 10kg/m³.

£40.15£48.18 Ex VATInc VAT
£3.22£3.86 Per m2 Get restock alert