Cavity Wall Insulation
- PIR rigid boards,
- Mineral wool,
- Full and partial fill cavity,
- Low lambda value,
- High performance
Two options are available when insulating a cavity wall:
FULL FILL CAVITY
- No need for a residual cavity.
- Suitable for mineral wool and some expanded polystyrene insulants.
- Insulation thickness varies according to the U-value requirement.
- Wall tie or suitable fixing is essential.
- Foil faced insulants are not suitable for this application.
- Suitable for natural insulation materials when used with a barrier
PARTIAL FILL CAVITY
- Residual cavity must be a minimum of 50mm.
- Suitable for all insulants.
- Thinner, foil faced insulation boards take advantage of reduction in heat radiance across the cavity and reach required U-value.
- Any problems associated with complete cavity fill can be avoided.
- Suitable for natural insulation materials when used with a barrier

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75mm URSA 32 Cavity Insulation Batt (pack of 6)
1200x455mm - 3.28m2 show quantity discountsDelivery Time: 1 - 2 days
Guide Price: £27.51 (£33.01 inc VAT)
£8.39/m2 (£10.07/m2 inc VAT)
show quantity discountsURSA Cavity Batt is a lightweight, semi rigid glass mineral wool slab treated with silicon based water repellent. It is suitable for use in both fully and partially filled masonry cavity walls up to 25m high. It is manufactured from an abundant, sustainable resource and may utilise up to 8..
75mm URSA 35 Cavity Insulation Batt (pack of 7)
1200x455mm - 3.82m2 show quantity discountsDelivery Time: 1 - 2 days
Guide Price: £11.92 (£14.30 inc VAT)
£3.12/m2 (£3.74/m2 inc VAT)
show quantity discounts75mm URSA Cavity Batt is a lightweight, semi rigid glass mineral wool slab treated with silicon based water repellent. It is suitable for use in both fully and partially filled masonry cavity walls up to 25m high. It is manufactured from an abundant, sustainable resource and may utilise up..
50mm Isover Hi-Cav CWS 32 - pack of 14
50mm CWS 32 - 7.64m2 Delivery Time: 2 - 3 days
50mm Isover CWS 32 batt is a dense glass wool insulation product, providing high thermal performance in masonry cavity wall insulation, applicable in various type of buildings including domestic, commercial, industrial, health, retail, education. The products density allows it to have extremely low ..
50mm Isover Cavity Wall Slabs (pack of 20)
455x1200mm - 10.92m2 show quantity discountsDelivery Time: 2 - 3 days
£37.91 (£45.49 inc VAT)
£3.47/m2 (£4.16/m2 inc VAT)
show quantity discounts50mm ISOVER Cavity Wall Slab (CWS) is a non-combustible, silicone impregnated glass mineral wool thermal insulation in masonry cavity walls in full-fill applications. It is designed to be installed during construction in the cavity between two masonry leaves in external walls. Meets Part L Buil..
50mm Superglass Superwall 36 Cavity Wall Batt (pack of 16)
1200x455mm - 8.74m2 Delivery Time: 1 - 2 days
50mm Superwall 36 Cavity Wall Batt is a lightweight, non-combustible, unfaced glass mineral wool batt for use as full or partial fill insulation in new external masonry cavity walls up to 25 m in height in domestic and non-domestic buildings. Superwall 36 is manufactured from nearly 84% recycled gla..
75mm DriTherm 32 Ultimate Cavity Slab Knauf (pack of 6)
1200x455mm - 3.28m2 show quantity discountsDelivery Time: 3 - 5 days
Guide Price: £21.68 (£26.02 inc VAT)
£6.61/m2 (£7.93/m2 inc VAT)
show quantity discounts75mm Earthwool DriTherm 32 Cavity Slab is a semi-rigid insulation material made from non-combustible, water repellent, glass mineral wool. They are 455mm wide to suit standard vertical wall tie spacings, ensuring a closed joint with adjacent slabs. Manufactured with Knauf ECOSE Technology - no ..
75mm Knauf DriTherm Cavity Slab 34 Super (pack of 10)
1200x455mm - 5.46m2 Delivery Time: 2 - 3 days
Guide Price: £28.22 (£33.86 inc VAT)
£5.17/m2 (£6.20/m2 inc VAT)
75mm Knauf Earthwool DriTherm Cavity Slab 34 Super are semi-rigid or rigid slabs of non-combustible, water repellent, glass mineral wool. They are 455mm wide to suit standard vertical wall tie spacings, ensuring a closed joint with adjacent slabs. This product has a special addit..
50mm DriTherm 37 Standard Cavity Slab Knauf (pack of 12)
1200x455 -6.55m2 show quantity discountsDelivery Time: 3 - 5 days
Guide Price: £17.50 (£21.00 inc VAT)
£2.67/m2 (£3.20/m2 inc VAT)
show quantity discounts50mm DriTherm 37 Standard Cavity Slabs are rigid slabs of non-combustible, glass mineral wool with a water-repellent additive. They are 455mm wide to suit standard vertical wall tie spacing, ensuring a closed joint with adjacent slabs. This product has a special additive to make it water r..
50mm Rockwool Cavity Insulation Batt (pack of 12)
1200x455 - 6.55m2 show quantity discountsDelivery Time: 1 - 2 days
£27.04 (£32.45 inc VAT)
£4.13/m2 (£4.96/m2 inc VAT)
show quantity discounts50mm Rockwool Cavity Batt provides a completely reliable and cost-effective method of insulating new masonry cavity wall construction. Its BBA certified for use as full fill cavity wall insulation and is effective in reducing the thermal transmittance (U value) of new external cavity walls with maso..
30mm Rockwool RW3 Slab (Prorox SL930) - pack of 15
1200x600mm - 10.8m2 Delivery Time: 1 - 2 days
Guide Price: £38.39 (£46.07 inc VAT)
£3.55/m2 (£4.26/m2 inc VAT)
30mm Rockwool RW3 Slab (Prorox SL 930) is a semi-rigid resin bonded slab, providing great thermal, acoustic and fire resistance, designed to be used in various applications in floors, walls and roofs, including special applications in industrial buildings for insulation of ships, offshore plat..
75mm Rockwool SP60 Firestop Cavity Slab (pack of 4)
1000x650mm - 2.60m2 Delivery Time: 2 - 3 days
Guide Price: £134.40 (£161.28 inc VAT)
£51.69/m2 (£62.03/m2 inc VAT)
75mm Rockwool SP60 Firestop Cavity Slab systems form cavity fire stops within commercial and industrial buildings. The solution may be installed horizontally or vertically and is suitable for varying cavity widths in masonry and curtain wall constructions. The product has been designed as a one-piec..
25mm Celotex CW4000 Rigid PIR Cavity Insulation Board (pack of 20)
1200x450mm - 10.8m2 show quantity discountsDelivery Time: 3 - 5 days
Guide Price: £90.55 (£108.66 inc VAT)
£8.38/m2 (£10.06/m2 inc VAT)
show quantity discounts25mm Celotex CW4000 is an insulation board aimed specifically at partial fill cavity wall applications. It comprises a polyisocyanurate rigid foam insulation core, with a thermal conductivity of 0.022 W/mK and low emissivity aluminium foil facings on both sides. CW4000 is manufactured from rigi..
25mm Celotex FR5000 Fire Resistant PIR Insulation Board (pack of 16)
1200x2400mm - 46.08m2
Celotex FR5025 is one of the available dimensions of the Celotex FR5000 PIR insulation boards made from polyisocyanurate rigid core and faced on both side with low emissivity aluminum foils for improved thermal performance. The product is applicable to different types of constructions incl..
97mm Celotex CF5000 - External Wall Cavity Full Fill Insulation Board - Pack of 6 - CF5097 -pallet of 16
1200 x 450mm - 51.84m2
Guide Price: £1,647.97 (£1,977.56 inc VAT)
£31.79/m2 (£38.15/m2 inc VAT)
97mm Celotex CF5000 is specifically designed for use within full fill cavity wall applications. It is in compliance to UK Building Regulations by achieving a U-value of 0.18 W/m 2 K, maximising thermal performance without widening the cavity. BBA certified, Celotex CF5000 features a mechanical..
35mm Xtratherm Thin-R XT/CW Partial Fill Cavity Insulation (pack of 9)
1200x450mm - 4.86m2 show quantity discountsDelivery Time: 2 - 4 days
Guide Price: £40.28 (£48.34 inc VAT)
£8.29/m2 (£9.95/m2 inc VAT)
show quantity discountsXtratherm ThinR XT/CW Partial Fill Cavity Wall Insulation is the best solution when designers or regulations demand additional thermal insulation in external masonry walls, without a substantial increase in the width of the cavity. Xtratherm Thin-R boards achieve high standards of insulation wh..
75mm Thin-R CT/PIR Cavity Therm Full Fill Insulation Xtratherm (pack of 4)
CT/PIR 1200x450 - 2.16m2 show quantity discountsDelivery Time: 2 - 3 days
Guide Price: £52.43 (£62.92 inc VAT)
£24.27/m2 (£29.12/m2 inc VAT)
show quantity discounts75mm Xtratherm CavityTherm wall insulation board is a high performance composite board of enhanced PIR core with a lambda value of 0.021W/mK. The boards have gas tight facings with one face bonded to a profiled HIPS skin during manufacture to provide a drainage plane. CavityTherms unique engineered ..
20mm Kooltherm K8 Phenolic Cavity Board Kingspan (pack of 25)
K8 1200x450 - 13.50m2
Kingspan Kooltherm K8 is the partial fill cavity wall insulation board comprising a premium performance rigid thermoset phenolic insulation core faced on both sides with a low emissivity composite foil facing. The product is manufactured with a blowing agent that has zero Ozone Depletion Potential (..
80mm Kingspan Kooltherm K106 Phenolic Cavity Board (pack of 6)
1200x450mm - 3.24m2
80mm Kingspan Kooltherm K106 Cavity Board is a premium performance rigid thermoset fibre-free phenolic insulation core bonded to a water-tight, vapour-open polypropylene fleece and to a inner facing of a low emissivity composite foil. It is specifically designed to limit thermal bridging a..
50mm Kingspan Kooltherm K108 Phenolic Cavity Board (pack of 10)
1200x450mm - 5.40 m2 show quantity discountsDelivery Time: 5 - 7 days
£92.04 (£110.45 inc VAT)
£17.04/m2 (£20.45/m2 inc VAT)
show quantity discounts50mm Kingspan Kooltherm K108 Cavity Board is a premium performance rigid thermoset fibre-free phenolic insulation core faced on both sides with a low emissivity composite foil. It is specifically designed to limit thermal bridging and uncontrolled airleakage via junctions in cavity wa..
10mm Grey Polystyrene (Graphite EPS) for External Wall Insulation (pack of 60)
1000x500mm - 30m2 Delivery Time: In Stock 1-2 working days
£29.99 (£35.99 inc VAT)
£1.00/m2 (£1.20/m2 inc VAT)
10mm Grey Polystyrene (Graphite) is a high quality expanded polystyrene (EPS) board enhanced with integrated graphite within its bead structure and of grey colour. The high-purity graphite particles integrated within the insulation beads reflects radiant heat and significantly improves insulati..
10mm White Polystyrene Board (EPS) for External Wall Insulation (pack of 60)
1000x500mm - 30m2 show quantity discountsDelivery Time: In Stock 1-2 working days
£27.50 (£33.00 inc VAT)
£0.92/m2 (£1.10/m2 inc VAT)
show quantity discounts10mm White Polystyrene Board is a very lightweight and easy to handle and install, expanded polystyrene (EPS) board specially designed to be used as a part of various external wall insulation systems. It can be used in applications requiring transfer of small mechanical loads.CHARACTERISTICSLightwei..
50mm Cavi-Mate EPS Cavity Closer
2.5m show quantity discountsDelivery Time: 1 - 2 days
£10.85 (£13.02 inc VAT)
show quantity discountsCavi-Mate EPS Cavity Closer is a new, robust window installation system ideal for the new build market. Manufactured from high quality PVC-U, it is a window former, locator and cavity closer, which enables Contractors to fit window frames quickly and easily by building around the sub-frame then fitt..
50mm Kingspan Thermabate Cavity Closer 3m length (pack of 10).
50x3000mm - Free Delivery Delivery Time: 3 - 5 days
Guide Price: £155.81 (£186.97 inc VAT)
50mm Thermabate is a cavity closer box section with a fibre free, rigid thermoset urethane insulation core that maintains continuous insulation around window and door openings. It is suitable for use with timber, metal or uPVC window frames. It provides a simple and effective method for closing cavi..
Insulation Retaining Clips (pack of 250) - Partial Fill Cavity Insulation
250 Delivery Time: 1 - 2 days
£18.50 (£22.20 inc VAT)
For use with standard wall ties in partial fill cavity wall insulating, suitable for PIR rigid insulation boards or wool slabs (batts).These clips hold insulation in place and help to keep the rest of the cavity space clear.Improve the effective thickness of a wall under loadMaintain the moisture br..
Flange Extension Clip for Kingspan Thermabate Cavity Closer 1m length
extensionclip Delivery Time: 2 - 3 days
Flange Extension Clip for connecting Kingspan Thermabate to extend the width of the fixing flange. It enables positive fixing of frame over suspect masonry. Supplied in one meter lengths. Colour coded to white. CERTIFICATIONKingspan Thermabate is manufactured to the highest standards ..
Jointing Clip for Kingspan Cavity Closer 1m length
jointingclip Delivery Time: 2 - 3 days
Jointing Clip connects two sections backtoback along their length to suit cavity widths of up to 300 mm in circumstances where a single section, Kingspan Kooltherm Thermabate Cavity Closer or Kingspan Kooltherm Cavity Closer will not suffice. It should be installed in 100 mm lengths at 300 mm centre..
Standard Flange Clip for Kingspan Thermabate Cavity Closer 1m length
flangeclip Delivery Time: 2 - 3 days
Guide Price: £2.46 (£2.95 inc VAT)
Standard Flange Clip for use with Kingspan Thermabate Cavity Closers and for use as a weather check, for fixing closer sections to window frames, and for retaining partial fill insulation batts in the cavity. Supplied in one meter lengths. Colour coded to green.CERTIFICATIONKingspan Thermabate is ma..
26mm Reveal Clip for Kingspan Thermabate Cavity Closer 1m length
revealclip Delivery Time: 2 - 3 days
26mm Reveal Clip to help construction of check reveals and gives additional protection to the frame assembly.Supplied in one meter lengths. Colour coded to white. CERTIFICATIONKingspan Thermabate is manufactured to the highest standards under a management system certified to ISO 9001: 2015..
Wall Ties 225mm - stainless steel (pack of 250).
WT225 - free delivery show quantity discountsDelivery Time: 1 - 2 days
£40.02 (£48.02 inc VAT)
show quantity discountsHousing Tie - Light Duty Wall Tie suitable for box form domestic dwellings with leaves of similar thickness up to 10m high.Tested as type A (sound)Tested as Type 4 (strength) to BS EN 845-1BBA CertifiedStainless SteelA number of key factors must be taken into consideration to conform to building reg..
Jointing Strip for Kingspan Cavity Closer 1m length
jointingstrip Delivery Time: 3 - 5 days
Jointing Strip that aligns and connects two abutting cavity closer sections along their crosssectional plane. It allows for opening sizes greater than 2.4 metres, and for the reduction of wastage through the use of offcuts. Limited to one butt joint per side of the opening.. Colour coded to Grey.CER..