Menu
Your Cart

PARTIAL FILL CAVITY INSULATION

PARTIAL FILL CAVITY INSULATION

Generally speaking partial fill cavity insulation leaves a 50mm gap between the insulation layer and the outer leaf of the wall, which acts as a barrier to prevent external moisture reaching the internal leaf and can be used on buildings of any height. The purpose of the air space in a cavity wall is as a barrier to the penetration of rainwater to the inside face of the wall. If the clear air space is to be effective as a barrier to rain penetration it should not be bridged by anything other than cavity ties. It is important to leave clear air space of all mortar droppings and other building debris that might serve as a path for water. Good practice, therefore, is to use a 50-60mm wide air space between the outer leaf and the partial fill insulation. To meet insulation requirements and the use of a 100mm cavity with partial fill insulation it may be economical to use a lightweight block inner leaf to augment the cavity insulation to bring the wall to the required U-value. Partial-fill is the standard choice for most new developments. The 50mm gap has the advantage of reducing the chance of any moisture that does penetrate the outer leaf bridging through to the internal structure. For that reason, the system is required by many local authority building control departments especially in the UK’s many ‘exposed’ locations. 

PARTIAL FILL MATERIALS

The materials used for partial fill insulation should be of boards, slabs or batts that are sufficiently rigid for ease of handling and to be retained in a vertical position against the inner leaf inside the cavity without sagging or losing shape, so that the edges of the boards remain close butted throughout the useful life of the building. They are supplied at 455mm wide to allow easy installation between standard vertical wall tie spacings and minimum on-site cutting and waste.

Those partial fill materials can be grouped as:

  • Inorganic insulants
  • Organic insulants

Organic insulants are made from naturally occurring materials that are formed into fibre, powder or cellular structures that have a high void content, as for example, glass fibre, mineral fibre (rockwool), cellular glass beads, vermiculite, calcium silicate and magnesia or as compressed cork. Organic insulants are generally non-combustible, do not support spread of flame, are rot and vermin proof and generally have a higher U-value than inorganic insulants. The organic insulants most used in the fabric of buildings are glass fibre and rockwool in the form of loose fibres, mats and rolls of felted fibres and semi-rigid and rigid boards, batts and slabs of compressed fibres, cellular glass beads fused together as rigid boards, compressed cork boards and vermiculite grains.

Inorganic insulants are based on hydrocarbon polymers in the form of thermnosetting or thermoplastic resins to form structures with a high void content, as for example polystyrene, polyurethane and phenolic. Inorganic insulants generally have a lower U-value than organic insulants, are combustible, support spread of flame more readily than organic insulants and have a comparatively low melting point. The inorganic insulants most used for the fabric of buildings are expanded polystyrene in the form of beads or boards, extruded polystyrene in the form of boards and polyurethane and phenolic foams in the form of preformed boards or spray coatings. With the recent increase in requirements for the insulation of walls it may well be advantageous to use one of the somewhat more expensive inorganic insulants such as XPS (extruded polystyrene), PIR (polyisocyanurate) or PUR (polyurethane) because of their lower U-value, where a 50mm clear air space is to be maintained in the cavity, without greatly increasing the overall width of the cavity.

Partial fill materials used as insulation for the buildings may be also grouped as:

  • Expanded Polystyrene
  • Phenolic Boards
  • PIR Boards
  • Mineral Wool Batts.

 

EXPANDED POLYSTYRENE

Partial Fill Polystyrene Cavity Wall Insulation Boards are a far more cost-effective alternative to PIR that offers a 20% reduction in thickness. This insulation will reduce your carbon footprint and help to decrease heating bills by limiting heat loss. Polystyrene Cavity Wall Insulation Board (EPS 70) (1200 x 450mm - coverage 0.54m²) is manufactured from low lambda polystyrene and is a square edged panel that offers excellent thermal performance when used within masonry wall constructions to satisfy the relevant U-value requirements. 

Products:

SPI Stylite Partial Fill EPS 

Jablite Partial-Fill Cavity Wall insulation  EPS 70 (white) and EPS HP 70 (grey) 

 

PHENOLIC BOARDS

Partial fill cavity board is a premium performance insulation with a fibre-free rigid thermoset phenolic core. It provides a level of performance that is unrivalled in the world of rigid thermoset insulation materials with a thermal conductivity of just 0.018 W/mK across all thicknesses. However, phenolic products are more expensive up front and installation can require more attention to detail on site.

Products:

SR/CW Cavity Wall Insulation Board Xtratherm Safe-R  

Kingspan Kooltherm K108 Phenolic Cavity Insulation Board 

 

PIR BOARDS

PIR partial fill cavity boards are a high performance insulation with a fibre-free rigid thermoset polyisocyanurate (PIR) core. They are used to insulate partial fill cavity walls, and have usually have a thermal conductivity of 0.022 W/mK. Rigid products offer better thermal performance allowing you to specify a thinner wall or achieve a better U-value at the same thickness. 

Products:

Kingspan® Thermawall TW50 

Celotex® CW4000 Cavity PIR Insulation Board

Xtratherm® XT/CW Thin-R Partial Fill Cavity Insulation

Xtratherm® Xtroliner XO/CW

 

MINERAL WOOL BATTS

Mineral wool partial fill batt is designed to provide thermal insulation in partial-fill external masonry cavity walls, with no height restriction (additional requirements apply for buildings above 25 metres in height for partial fill). It can be used regardless of height and in cavities in areas of 'very severe' exposure without rendering the outer leaf. Semi-rigid batts of glass mineral wool or rockwool are the traditional choice. Their flexibility allows them to fit snugly against the masonry as well as knit together at abutments.

Products:

Rockwool® HP Partial Fill Cavity Slab

Knauf Rocksilk® RainScreen Slab

URSA 32 Cavity Wall Insulation Batts

Superglass® Superwall 36 

URSA® 32 Cavity Wall Insulation Batts

 

PARTIAL FILL CAVITY INSTALLATION

Usual practice is to build the inner leaf of the cavity wall first, up to the first horizontal row of wall ties, then place the insulation boards in position against the inner leaf. Then as the outer leaf is built, a batten may be suspended in the cavity air space and raised to the level of the first row of wall ties and the batten is then withdrawn and cleared of droppings. Insulation retaining wall ties arc then bedded across the cavity to tie the leaves and retain the insulation in position and the sequence of operations is repeated at each level of wall ties. Insulation retaining ties are usually standard galvanised steel or stainless steel wall ties to which a plastic disc is clipped to retain the edges of the insulation. The ties may be set in line one over the other at the edges of boards, so that the retaining clips retain the corners of four insulation boards.

 

Related articles:

All types of partial fill cavity insulation

How to choose the right Kingspan insulation board for construction?

How to work out how many square metres of insulation I would need?

Cavity wall. All you need to know

Best 6 passive fire protection cavity barriers.

4 types of full fill cavity insulation explained

Cheaper alternative/equivalent to kingspan insulation


Video credit:https://www.youtube.com/watch?v=3zPD3JOfj80&t=26s

Brand: Unilin Insulation (UK) known as Xtratherm Model: 100mm Unilin ECO/CW
100mm Unilin ECO/CW Cavity Wall 360 is a partial fill cavity wall insulation board, a rigid PIR insulation core with textured robust low emissivity foil facings and engineered shiplap jointing. Unilin ECO/CW 360 cavity system incorporates robust facings, engineered jointing details, preformed cor..
  • 100mm x 450mm x 1200mm Unilin ECO/CW 360 Cavity Wall Insulation
  • Partial fill cavity wall insulation board with an engineered shiplap jointing
  • ECO/CW can achieve a Passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Minimising the threat of Thermal Bridging and improving the U-Value of the wall
  • Premium modified PIR insulation core with textured robust low emissivity foil facings
£ 137.88
Ex Tax:£ 114.90
Estimated delivery: 5-7 working days
Brand: Celotex® Model: 25mm CW4000
25mm Celotex CW4000 Partial Fill Cavity Wall Insulation Board (CW4025) is an easy to install PIR (polyisocyanurate) rigid insulation board, featuring a low emissivity foil facings with excellent thermal conductivity of 0.022 W/mk that is suitable for partial fill masonry cavity wall applications. ..
  • Lightweight - Squared edges
  • Partial Fill Masonry Cavity Walls
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificate 16/5343
£ 137.88
Ex Tax:£ 114.90
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 25mm Unilin XT/CW
25mm Unilin Thin-R XT/CW PIR Cavity Insulation Board is used in traditional masonry walls, built to the highest thermal standards whilst maintaining a residual cavity, offering protection from wind driven rain. Unilin Cavity Wall (T&G) tongue and groove jointing offers a practical onsite solution..
  • 25mm Unilin Thin-R XT/CW Partial Fill Cavity Wall Insulation Board
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CW improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 143.88
Ex Tax:£ 119.90
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 40mm TW50
40mm Kingspan TW50 Thermawall Cavity Wall Insulation Board is a high-efficiency, BBA certified cavity insulation board designed for partial fill masonry cavity walls. Thermawall TW50 is a stable and rot proof cavity wall insulation board used in newbuild and extension projects and will remain eff..
  • Low emissivity foil facings
  • Easy to handle and install
  • Thermal conductivity 0.022 W/m.K
  • BBA Certificate 14/5133
  • Non–deleterious material
£ 128.78
Ex Tax:£ 107.32
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 40mm XT/CW
40mm Xtratherm XT/CW Partial Fill Cavity Wall is a high-quality, BBA certified, tongue and groove PIR insulation board with certified thermal conductivity of 0.022 W/mK designed for use in traditional masonry partial fill cavity walls. Xtratherm Cavity Wall is a highly-durable, rot proof insulati..
  • BBA Certification No. 08/4613
  • Board coverage : 0.54m2
  • Pack coverage: 4.86m2
  • R-Value:  1.8m2K/W
  • Surface spread of flame: Class 1
£ 105.79
Ex Tax:£ 88.16
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 50mm SR/CW Cavity Insulation
50mm SR/CW Partial Fill Cavity Wall Insulation Xtratherm Safe-R is a top-class phenolic foam rigid cavity insulation board with a low emissivity foil facings designed for use in traditional masonry walls. A high-performance BBA certified 1200mm x 450mm x 50mm square edge board with an approved th..
  • Thermal Conductivity: 0.021W/mK
  • For New Build or Refurbishment
  • Reaction to Fire Euroclass D -s1, d0
  • BBA Certification No. 10/4803
  • BRE Green Guide A+ Rated - Building Regulations
£ 117.85
Ex Tax:£ 98.21
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 50mm Unilin SR/CW Cavity Walls
50mm Unilin SR/CW is a partial fill cavity wall insulation board used for traditional masonry walls, achieves excellent U-Values whilst maintaining a residual cavity, offering protection from wind driven rain. Unilin Safe-R SR/CW is manufactured to EN 13166 by Unilin Insulation with certified lam..
  • 50mm Unilin SR/CW Phenolic Insulation Board for Partial Fill Cavity Walls
  • Safe-R SR/CW improves U-Values and meets Future Homes standards
  • SR/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.020 W/mK and Euroclass D-s1 d0
£ 143.88
Ex Tax:£ 119.90
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 50mm Unilin XO/CW Cavity
50mm XO/CW T&G Unilin, comprising a rigid polyisocyanurate (PIR) foam insulation board with a textured aluminium foil-facing on both sides, for use as partial fill insulation. Xtroliner XO/CW improves U-Values and meets Future Homes standards, providing an excellent choice for passive and low ene..
  • 50mm Unilin XO/CW T&G Insulation Board for Partial Fill Cavity Walls
  • Xtroliner XO/CW improves U-Values and meets Future Homes standards
  • XO/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.021 W/mK and Euroclass C s2 d0 fire class
£ 119.88
Ex Tax:£ 99.90
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 50mm Unilin XT/CWP (T&G)
50mm Unilin XT/CWP Thin-R Plus Partial Fill Cavity is a partial fill cavity system with engineered tongue and grooved joints to ensure insulation continuity and minimisation of thermal bridging. The lower lambda (thermal conductivity) of 0.021 W/mK improves U-Values of the cavity and meets Future..
  • 50mm Unilin Thin-R PLUS XT/CWP Partial Fill Cavity Wall Insulation
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CWP improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 107.17
Ex Tax:£ 89.31
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 50mm XT/CWP Cavity PLUS
50mm Xtratherm Thin-R XT/CWP Cavity Wall Plus is a robust tongue and groove jointing PIR (polyisocyanurate) rigid insulation board with a low emissivity foil facings, used for traditional masonry partial fill cavity walls. XT/CWP Cavity Wall Plus (T&G) is the best solution when building tradition..
  • 50mm Xtratherm XT/CWP Cavity Wall Plus Insulation Board
  • Lower Lambda value (thermal conductivity) of 0.021 W/mK
  • Enhanced performance PIR (polyisocyanurate) rigid insulation
  • Easy to install tongue and groove (T&G) jointing system
  • Used as a traditional masonry partial fill cavity wall insulation
£ 117.66
Ex Tax:£ 98.05
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 50mm XO/CW
50mm Xtratherm Xtroliner XO/CW is an improved performance PIR (polyisocyanurate) tongue and groove insulation board with robust foil facings designed for partial fill cavity wall insulation with an approved thermal conductivity (lambda value) as low as 0.021W/mK. This lower lambda improves U-Valu..
  • A + rating under the BRE Green Guide
  • Thermal Conductivity: 0.021W/mK
  • Reaction to Fire Euroclass C-s1, d0
  • (T&G) tongue and groove jointing
  • BBA Certificate 12/4956 - Building Regulations
£ 132.14
Ex Tax:£ 110.12
Estimated delivery: 5-7 working days
Brand: URSA® Model: 75mm URSA TERRA 32
75mm URSA 32 Cavity Wall Insulation Batt is a non-combustible class A1 fire rated, semi rigid glass mineral wool slab treated with silicone water-repellent additive designed for use as either a full or partial fill masonry cavity wall insulation for buildings up to 25meters in height. URSA 32 Cav..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.032W/mK
  • BBA Certificate 09/4624 ǀ Density of 32 kg/m3
£ 76.22
Ex Tax:£ 63.52
Estimated delivery: 3-5 working days
Brand: URSA® Model: 75mm URSA TERRA 35
75mm URSA 35 Cavity Wall Batt is a non-combustible, A1 fire rated, semi rigid glass mineral wool cavity insulation slab with certified thermal conductivity of 0.035W/mK and density of 22kg/m3, used in full fill or partial fill external masonry cavity walls. URSA 35 Cavity Wall Insulation Batt 75m..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.035W/mK
  • BBA Certificate 09/4624 ǀ Density of 22 kg/m3
£ 67.50
Ex Tax:£ 56.25
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 40mm Kooltherm® K108
The 40mm Kingspan Kooltherm K108 is a partial fill cavity wall insulation board, an advanced phenolic fibre-free rigid thermoset insulation core with certified thermal conductivity of 0.019 W/mK. K108 Phenolic Cavity Board 40mm x 450mm x 1200mm is a one of the thinnest commonly used insulation fo..
  • Kingspan Kooltherm K108 Partial Fill Cavity Insulation Board 40mm
  • Premium performance lower lambda (0.019 W/mK) cavity insulation
  • Significantly increases the thermal resistance of the cavity walls
  • Kooltherm® Kingspan K108 Phenolic Cavity Board 450mm x 1200mm
  • Achieves the same U-value as an alternative products with a thinner board
£ 191.88
Ex Tax:£ 159.90
Estimated delivery: 5-7 working days
Brand: URSA® Model: 100mm URSA TERRA 35
100mm URSA 35 Cavity Wall Batt is an A1 non-combustible semi rigid glasswool cavity insulation slab with certified thermal conductivity of 0.035W/mK and nominal density of 22kg/m3, used in full fill or partial fill external masonry cavity walls. URSA 35 Cavity Wall Insulation Batt 100mm x 455mm x..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.035W/mK
  • BBA Certificate 09/4624 ǀ Density of 22 kg/m3
£ 66.56
Ex Tax:£ 55.47
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 110mm Unilin ECO/CW
110mm Unilin ECO/CW 360 Cavity is a rigid PIR insulation board with textured robust low emissivity foil facings and engineered shiplap jointing used as a partial fill cavity wall insulation. Unilin ECO/CW cavity system incorporates robust facings, engineered rebated jointing details, preformed co..
  • 110mm x 450mm x 1200mm Unilin ECO/CW 360 Cavity Wall Insulation
  • Partial fill cavity wall insulation board with an engineered shiplap jointing
  • ECO/CW can achieve a Passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Minimising the threat of Thermal Bridging and improving the U-Value of the wall
  • Premium modified PIR insulation core with textured robust low emissivity foil facings
£ 149.88
Ex Tax:£ 124.90
Estimated delivery: 5-7 working days
Brand: Celotex® Model: 40mm CW4000
40mm Celotex CW4000 Partial Fill Cavity Wall Insulation Board (CW4040) is an easy to install PIR (polyisocyanurate) rigid insulation board, featuring a low emissivity foil facings with excellent thermal conductivity of 0.022 W/mk that is suitable for partial fill masonry cavity wall applications. ..
  • Lightweight - Squared edges
  • Partial Fill Masonry Cavity Walls
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificate 16/5343
£ 83.88
Ex Tax:£ 69.90
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 40mm Unilin XT/CW
40mm Unilin Thin-R XT/CW PIR Cavity Insulation Board is a traditional masonry wall cavity board offering highest thermal standards whilst maintaining a residual cavity, offering protection from wind driven rain. Unilin Cavity Wall (T&G) tongue and groove jointing offers a practical onsite solutio..
  • 40mm Unilin Thin-R XT/CW Partial Fill Cavity Wall Insulation Board
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CW improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 107.88
Ex Tax:£ 89.90
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 45mm TW50
45mm Kingspan TW50 Thermawall is a high-performance cavity wall insulation board with a rigid thermoset polyisocyanurate (PIR) core designed for partial fill masonry cavity walls. Thermawall TW50 is a stable and rot proof insulation board used in newbuild or extension projects and will remain eff..
  • Low emissivity foil facings
  • Easy to handle and install
  • Thermal conductivity 0.022 W/m.K
  • BBA Certificate 14/5133
  • Non–deleterious material
£ 101.88
Ex Tax:£ 84.90
Estimated delivery: 7-10 working days
Brand: Xtratherm® Model: 45mm XT/CW
45mm Xtratherm XT/CW Partial Fill Cavity Wall is a high-quality, BBA certified, tongue and groove PIR insulation board with certified thermal conductivity of 0.022 W/mK designed for use in traditional masonry partial fill cavity walls. Xtratherm Cavity Wall is a highly-durable, rot proof insulati..
  • BBA Certification No. 08/4613
  • Board coverage : 0.54m2
  • Pack coverage: 4.86m2
  • R-Value:  2.025m2K/W
  • Surface spread of flame: Class 1
£ 112.82
Ex Tax:£ 94.02
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 50mm Kooltherm® K108
50mm Kingspan K108 Cavity Insulation Board is an advanced partial-fill cavity wall insulation, K108 Kingspan achieves the same wall U-value as alternative products with a much thinner profile. K108 Phenolic Cavity Board 50mm x 450mm x 1200mm is a one of the thinnest commonly used insulation for p..
  • Kingspan Kooltherm K108 Partial Fill Cavity Insulation Board 50mm
  • Premium performance lower lambda (0.019 W/mK) cavity insulation
  • Significantly increases the thermal resistance of the cavity walls
  • Kooltherm® Kingspan K108 Phenolic Cavity Board 450mm x 1200mm
  • Achieves the same U-value as an alternative products with a thinner board
£ 155.88
Ex Tax:£ 129.90
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 60mm XT/CWP Cavity PLUS
60mm XT/CWP Xtratherm Thin-R Cavity Wall Plus is an enhanced performance PIR (polyisocyanurate) rigid insulation board with a robust tongue and groove jointing, used as a traditional masonry partial fill cavity wall insulation. XT/CWP Cavity Wall Plus (T&G) is the best solution when building trad..
  • 60mm Xtratherm XT/CWP Cavity Wall Plus Insulation Board
  • Lower Lambda value (thermal conductivity) of 0.021 W/mK
  • Enhanced performance PIR (polyisocyanurate) rigid insulation
  • Easy to install tongue and groove (T&G) jointing system
  • Used as a traditional masonry partial fill cavity wall insulation
£ 129.32
Ex Tax:£ 107.77
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 60mm SR/CW Cavity Insulation
60mm SR/CW Partial Fill Cavity Wall Insulation Xtratherm Safe-R is a top-class phenolic foam rigid cavity insulation board with a low emissivity foil facings designed for use in traditional masonry walls. A high-performance BBA certified 1200mm x 450mm x 60mm square edge board with an approved th..
  • Thermal Conductivity: 0.020W/mK
  • For New Build or Refurbishment
  • Reaction to Fire Euroclass D -s1, d0
  • BBA Certification No. 10/4803
  • BRE Green Guide A+ Rated - Building Regulations
£ 128.09
Ex Tax:£ 106.74
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 60mm Unilin SR/CW Cavity Walls
60mm SR/CW Unilin Safe-R is a rigid foam phenolic insulation core between low emissivity foil facings used for traditional cavity masonry walls, achieves excellent U-Values whilst maintaining a residual cavity. Unilin Safe-R SR/CW is manufactured to EN 13166 by Unilin Insulation with certified la..
  • 60mm Unilin SR/CW Phenolic Insulation Board for Partial Fill Cavity Walls
  • Safe-R SR/CW improves U-Values and meets Future Homes standards
  • SR/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.020 W/mK and Euroclass D-s1 d0
£ 155.88
Ex Tax:£ 129.90
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 60mm Unilin XO/CW Cavity
60mm Unilin XO/CW T&G is used to reduce the thermal transmittance of cavity walls in new buildings of a domestic or nondomestic nature with masonry inner and outer leaves. Xtroliner XO/CW improves U-Values and meets Future Homes standards, providing an excellent choice for passive and low energy ..
  • 60mm Unilin XO/CW T&G Insulation Board for Partial Fill Cavity Walls
  • Xtroliner XO/CW improves U-Values and meets Future Homes standards
  • XO/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.021 W/mK and Euroclass C s2 d0 fire class
£ 125.88
Ex Tax:£ 104.90
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 60mm Unilin XT/CWP (T&G)
60mm Unilin XT/CWP (T&G) Partial Fill Cavity Walls is an engineered tongue and grooved joint partial fill cavity system used to ensure insulation continuity and minimisation of thermal bridging. The lower lambda (thermal conductivity) of 0.021 W/mK improves U-Values of the cavity and meets Future..
  • 60mm Unilin Thin-R PLUS XT/CWP Partial Fill Cavity Wall Insulation
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CWP improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 113.88
Ex Tax:£ 94.90
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 60mm XO/CW
60mm Xtratherm Xtroliner XO/CW is an improved performance PIR (polyisocyanurate) tongue and groove insulation board with robust foil facings designed for partial fill cavity wall insulation with an approved thermal conductivity (lambda value) as low as 0.021W/mK. This lower lambda improves U-Valu..
  • A + rating under the BRE Green Guide
  • Thermal Conductivity: 0.021W/mK
  • Reaction to Fire Euroclass C -s1, d0
  • (T&G) tongue and groove jointing
  • BBA Certificate 12/4956 - Building Regulations
£ 141.02
Ex Tax:£ 117.52
Estimated delivery: 5-7 working days
Brand: URSA® Model: 85mm URSA TERRA 32
85mm Cavity Wall Insulation Batt URSA 32 is an A1, non-combustible semi rigid glass mineral wool cavity slab with silicone water repellent additive used as either a full or partial fill masonry cavity wall insulation for buildings up to 25meters in height. URSA 32 Cavity 85mm is manufactured in 1..
  • 85mm URSA 32 Cavity Wall Insulation Batts A1
  • Full or Partial Fill Masonry Cavity Walls Insulation
  • Glass mineral wool cavity slab Non-combustible
  • Certified thermal conductivity of 0.032W/mK
  • BBA Certificate 09/4624 ǀ Density of 32 kg/m3
£ 81.90
Ex Tax:£ 68.25
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 100mm ECO/CW Internal Corner
100mm Internal Corner Unilin ECO/CW 360 Cavity is used as a partial fill cavity wall insulation system to minimise the threat of Thermal Bridging and improve the overall U-Value of the wall. Unilin ECO/CW cavity system incorporates robust facings, engineered rebated jointing details, preformed co..
  • 100mm Internal Corner for Unilin ECO/CW 360 Cavity Wall Insulation
  • Partial fill cavity wall insulation board with an engineered shiplap jointing
  • ECO/CW can achieve a Passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Minimising the threat of Thermal Bridging and improving the U-Value of the wall
  • Premium modified PIR insulation core with textured robust low emissivity foil facings
£ 137.88
Ex Tax:£ 114.90
Estimated delivery: 5-7 working days
Brand: URSA® Model: 100mm URSA TERRA 32
100mm URSA 32 Cavity Wall Insulation Batt is a semi rigid glass mineral wool cavity slab with silicone water repellent additive designed for use in full fill or partial fill external masonry cavity wall insulation for buildings up to 25m in height. URSA 32 Cavity Slab is manufactured in 1200mm x ..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.032W/mK
  • BBA Certificate 09/4624 ǀ Density of 32 kg/m3
£ 80.86
Ex Tax:£ 67.38
Estimated delivery: 3-5 working days
Brand: URSA® Model: 125mm URSA TERRA 35
125mm URSA 35 Cavity Wall Batt is a semi rigid glasswool cavity insulation slab with certified thermal conductivity of 0.035W/mK and nominal density of 22kg/m3, used in full fill or partial fill external masonry cavity walls. URSA 35 Cavity Wall Insulation Batt 125mm x 450mm x 1200mm is an easy t..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.035W/mK
  • BBA Certificate 09/4624 ǀ Density of 22 kg/m3
£ 65.10
Ex Tax:£ 54.25
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 45mm Unilin XT/CW
45mm Unilin Thin-R XT/CW is a partial fill cavity wall insulation board with engineered tongue and grooved joint and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging. Unilin Cavity Wall (T&G) tongue and groove jointing offers a practical onsite solution that..
  • 45mm Unilin Thin-R XT/CW Partial Fill Cavity Wall Insulation Board
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CW improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 118.97
Ex Tax:£ 99.14
Estimated delivery: 3-5 working days
Brand: Celotex® Model: 50mm CW4000
50mm Celotex CW4000 Partial Fill Cavity Wall Insulation Board (CW4050) is an easy to install PIR (polyisocyanurate) rigid insulation board, featuring a low emissivity foil facings with excellent thermal conductivity of 0.022 W/mk that is suitable for partial fill masonry cavity wall applications. ..
  • Lightweight - Squared edges
  • Partial Fill Masonry Cavity Walls
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificate 16/5343
£ 95.88
Ex Tax:£ 79.90
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 50mm TW50
50mm Kingspan TW50 Thermawall Cavity Wall PIR Insulation Board is an advanced cavity wall insulation board suitable for partial fill masonry cavity walls. Thermawall TW50 is a stable and rot proof insulation board used in newbuild or extension projects and will remain effective for the life span ..
  • Low emissivity foil facings
  • Easy to handle and install
  • Thermal conductivity 0.022 W/m.K
  • BBA Certificate 14/5133
  • Non–deleterious material
£ 130.79
Ex Tax:£ 108.99
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 50mm XT/CW
50mm Xtratherm XT/CW Partial Fill Cavity Wall is a high-quality, BBA certified, tongue and groove PIR rigid insulation board with certified thermal conductivity of 0.022 W/mK designed for use in traditional masonry partial fill cavity walls. Xtratherm Cavity Wall is a highly-durable, rot proof in..
  • Size: 1200mm x 450mm
  • Board coverage : 0.54m2
  • Pack coverage: 4.86m2
  • R-Value:  2.25m2K/W
  • Surface spread of flame: Class 1
£ 98.23
Ex Tax:£ 81.86
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 70mm Unilin XT/CWP (T&G)
70mm Unilin XT/CWP (T&G) Thin-R Plus Cavity Walls is the best insulation solution when building traditional masonry walls to the highest thermal standards whilst maintaining a residual cavity. The lower lambda (thermal conductivity) of 0.021 W/mK improves U-Values of the cavity and meets Future H..
  • 70mm Unilin Thin-R PLUS XT/CWP (T&G) Partial Fill Cavity Wall Insulation
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CWP improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 107.82
Ex Tax:£ 89.85
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 70mm XT/CWP Cavity PLUS
70mm Xtratherm Plus Cavity Wall Board XT/CWP is an improved lambda value tongue and groove jointing polyisocyanurate rigid insulation board with a low emissivity foil facings, used for traditional masonry partial fill cavity walls. XT/CWP Cavity Wall Plus (T&G) is the best solution when building ..
  • 70mm Xtratherm XT/CWP Cavity Wall Plus Insulation Board
  • Lower Lambda value (thermal conductivity) of 0.021 W/mK
  • Enhanced performance PIR (polyisocyanurate) rigid insulation
  • Easy to install tongue and groove (T&G) jointing system
  • Used as a traditional masonry partial fill cavity wall insulation
£ 127.20
Ex Tax:£ 106.00
Estimated delivery: 3-5 working days
Brand: Xtratherm® Model: 75mm SR/CW Cavity Insulation
75mm SR/CW Partial Fill Cavity Wall Insulation Xtratherm Safe-R is a top-class phenolic foam rigid cavity insulation board with a low emissivity foil facings designed for use in traditional masonry walls. A high-performance BBA certified 1200mm x 450mm x 75mm square edge board with an approved th..
  • Thermal Conductivity: 0.020W/mK
  • For New Build or Refurbishment
  • Reaction to Fire Euroclass D -s1, d0
  • BBA Certification No. 10/4803
  • BRE Green Guide A+ Rated - Building Regulations
£ 112.70
Ex Tax:£ 93.92
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 75mm Unilin SR/CW Cavity Walls
75mm Unilin SR/CW is used as a partial fill insulation in external cavity walls with masonry inner and outer leaves, in new domestic and commercial buildings, offering protection from wind driven rain. Unilin Safe-R SR/CW is manufactured to EN 13166 by Unilin Insulation with certified lambda (the..
  • 75mm Unilin SR/CW Phenolic Insulation Board for Partial Fill Cavity Walls
  • Safe-R SR/CW improves U-Values and meets Future Homes standards
  • SR/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.020 W/mK and Euroclass D-s1 d0
£ 117.00
Ex Tax:£ 97.50
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 75mm Unilin XO/CW Cavity
75mm Unilin XO/CW is used as partial fill cavity insulation to reduce the thermal transmittance of cavity walls in new buildings of a domestic or nondomestic nature. Xtroliner XO/CW improves U-Values and meets Future Homes standards, providing an excellent choice for passive and low energy builds..
  • 75mm Unilin XO/CW T&G Insulation Board for Partial Fill Cavity Walls
  • Xtroliner XO/CW improves U-Values and meets Future Homes standards
  • XO/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.021 W/mK and Euroclass C s2 d0 fire class
£ 117.00
Ex Tax:£ 97.50
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 75mm XO/CW
75mm Xtratherm Xtroliner XO/CW is an improved performance PIR (polyisocyanurate) tongue and groove insulation board with robust foil facings designed for partial fill cavity wall insulation with an approved thermal conductivity (lambda value) as low as 0.021W/mK. This lower lambda improves U-Valu..
  • A + rating under the BRE Green Guide
  • Thermal Conductivity: 0.021W/mK
  • Reaction to Fire Euroclass C -s1, d0
  • (T&G) tongue and groove jointing
  • BBA Certificate 12/4956 - Building Regulations
£ 113.28
Ex Tax:£ 94.40
Estimated delivery: 5-7 working days
Brand: Kingspan® Model: 60mm Kooltherm® K108
Kingspan Kooltherm K108 Partial Fill Cavity Wall Board 60mm is a premium performance lower lambda (0.019W/mK) insulation used as an advanced partial-fill cavity wall insulation board. K108 Phenolic Cavity Board 60mm x 450mm x 1200mm is a one of the thinnest commonly used insulation for partial fi..
  • Kingspan Kooltherm K108 Partial Fill Cavity Insulation Board 60mm
  • Premium performance lower lambda (0.019 W/mK) cavity insulation
  • Significantly increases the thermal resistance of the cavity walls
  • Kooltherm® Kingspan K108 Phenolic Cavity Board 450mm x 1200mm
  • Achieves the same U-value as an alternative products with a thinner board
£ 155.88
Ex Tax:£ 129.90
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 110mm ECO/CW Internal Corner
110mm Internal Corner Board is used in Unilin ECO/CW 360 partial fill cavity wall insulation system to minimise the threat of Thermal Bridging and improve the overall U-Value of the wall. Unilin ECO/CW cavity system incorporates robust facings, engineered rebated jointing details, preformed corne..
  • 110mm Internal Corner for Unilin ECO/CW 360 Cavity Wall Insulation
  • Partial fill cavity wall insulation board with an engineered shiplap jointing
  • ECO/CW can achieve a Passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Minimising the threat of Thermal Bridging and improving the U-Value of the wall
  • Premium modified PIR insulation core with textured robust low emissivity foil facings
£ 149.88
Ex Tax:£ 124.90
Estimated delivery: 5-7 working days
Brand: URSA® Model: 125mm URSA TERRA 32
125mm URSA 32 Lightweight Cavity Wall Insulation Batt is a non-combustible semi rigid glass mineral wool slab treated with silicone water-repellent additive designed for use as either a full or partial fill masonry cavity wall insulation for buildings up to 25meters in height. URSA 32 Cavity Slab..
  • Non-combustible Class A1 Cavity Batt
  • Full or Partial Fill Masonry Cavity Walls
  • Semi rigid glass mineral wool cavity slab
  • Certified thermal conductivity of 0.032W/mK
  • BBA Certificate 09/4624 ǀ Density of 32 kg/m3
£ 62.88
Ex Tax:£ 52.40
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 50mm Unilin XT/CW
50mm Unilin XT/CW PIR Cavity Insulation Board is a tongue and grooved (T&G) joint cavity wall board with pre-formed corners, ensuring cavity wall insulation continuity and minimisation of thermal bridging. Unilin Cavity Wall (T&G) tongue and groove jointing offers a practical onsite solution that..
  • 50mm Unilin Thin-R XT/CW Partial Fill Cavity Wall Insulation Board
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CW improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 95.92
Ex Tax:£ 79.93
Estimated delivery: 3-5 working days
Brand: Celotex® Model: 55mm CW4000
55mm Celotex CW4000 Partial Fill Cavity Wall Insulation Board (CW4055) is an easy to install PIR (polyisocyanurate) rigid insulation board, featuring a low emissivity foil facings with excellent thermal conductivity of 0.022 W/mk that is suitable for partial fill masonry cavity wall applications. ..
  • Lightweight - Squared edges
  • Partial Fill Masonry Cavity Walls
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificate 16/5343
£ 113.88
Ex Tax:£ 94.90
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 55mm TW50
55mm Kingspan TW50 Thermawall Cavity Wall Insulation Board is a rigid thermoset polyisocyanurate (PIR) board designed for partial fill masonry cavity walls. Thermawall TW50 is a stable and rot proof insulation board used in newbuild or extension projects and will remain effective for the life spa..
  • Low emissivity foil facings
  • Easy to handle and install
  • Thermal conductivity 0.022 W/m.K
  • BBA Certificate 14/5133
  • Non–deleterious material
£ 119.88
Ex Tax:£ 99.90
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 55mm XT/CW
55mm Xtratherm XT/CW Partial Fill Cavity Wall is a high-quality, BBA certified, tongue and groove PIR insulation board with certified thermal conductivity of 0.022 W/mK designed for use in traditional masonry partial fill cavity walls. Xtratherm Cavity Wall is a highly-durable, rot proof insulati..
  • BBA Certification No. 08/4613
  • Board coverage : 0.54m2
  • Pack coverage: 4.86m2
  • R-Value:  2.475m2K/W
  • Surface spread of flame: Class 1
£ 129.19
Ex Tax:£ 107.66
Estimated delivery: 3-5 working days
Brand: Kingspan® Model: 70mm Kooltherm® K108
Kooltherm K108 Kingspan Cavity Wall Insulation Board is a 70mm thick lower lambda (0.019W/mK) partial-fill phenolic cavity wall insulation board. K108 Phenolic Cavity Board is a one of the thinnest commonly used insulation for partial fill cavity walls providing ultra low thermal conductivity tha..
  • Kingspan Kooltherm K108 Partial Fill Cavity Insulation Board 70mm
  • Premium performance lower lambda (0.019 W/mK) cavity insulation
  • Significantly increases the thermal resistance of the cavity walls
  • Kooltherm® Kingspan K108 Phenolic Cavity Board 450mm x 1200mm
  • Achieves the same U-value as an alternative products with a thinner board
£ 146.88
Ex Tax:£ 122.40
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 75mm XT/CWP Cavity PLUS
75mm Xtratherm XT/CWP Cavity Wall Plus is a high performance foil faced Polyisocyanurate (PIR) rigid insulation board with a robust tongue and groove jointing, used as a traditional masonry partial fill cavity wall insulation. XT/CWP Cavity Wall Plus (T&G) is the best solution when building tradi..
  • 75mm Xtratherm XT/CWP Cavity Wall Plus Insulation Board
  • Lower Lambda value (thermal conductivity) of 0.021 W/mK
  • Enhanced performance PIR (polyisocyanurate) rigid insulation
  • Easy to install tongue and groove (T&G) jointing system
  • Used as a traditional masonry partial fill cavity wall insulation
£ 138.83
Ex Tax:£ 115.69
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 75mm Unilin XT/CWP (T&G)
75mm Unilin XT/CWP (T&G) PIR Plus Partial Fill Cavity is a rigid enhanced PIR partial fill cavity system with engineered tongue and grooved joints offering excellent protection from wind driven rain. The lower lambda (thermal conductivity) of 0.021 W/mK improves U-Values of the cavity and meets F..
  • 75mm Unilin Thin-R PLUS XT/CWP (T&G) Partial Fill Cavity Wall Insulation
  • Reduced the Thermal Bridging and improved the U-Value of the wall
  • Low emissivity foil facing on XT/CWP improves the thermal performance
  • Recommended residual cavity width is 50mm (Building Regulations)
  • Most effective method of preventing wind-driven rain penetrating a wall
£ 113.34
Ex Tax:£ 94.45
Estimated delivery: 3-5 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 80mm Unilin SR/CW Cavity Walls
80mm Unilin SR/CW Cavity Board consists of closed-cell rigid phenolic (PF) foam, faced with composite foil facings used for traditional masonry walls to achieve U-Values asked for under the building regulations. Unilin Safe-R SR/CW is manufactured to EN 13166 by Unilin Insulation with certified l..
  • 80mm Unilin SR/CW Phenolic Insulation Board for Partial Fill Cavity Walls
  • Safe-R SR/CW improves U-Values and meets Future Homes standards
  • SR/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.020 W/mK and Euroclass D-s1 d0
£ 131.88
Ex Tax:£ 109.90
Estimated delivery: 5-7 working days
Brand: Xtratherm® Model: 80mm SR/CW Cavity Insulation
80mm SR/CW Partial Fill Cavity Wall Insulation Xtratherm Safe-R is a top-class phenolic foam rigid cavity insulation board with a low emissivity foil facings designed for use in traditional masonry walls. A high-performance BBA certified 1200mm x 450mm x 80mm square edge board with an approved th..
  • Thermal Conductivity: 0.020W/mK
  • For New Build or Refurbishment
  • Reaction to Fire Euroclass D -s1, d0
  • BBA Certification No. 10/4803
  • BRE Green Guide A+ Rated - Building Regulations
£ 117.49
Ex Tax:£ 97.91
Estimated delivery: 5-7 working days
Brand: Unilin Insulation (UK) known as Xtratherm Model: 80mm Unilin XO/CW Cavity
80mm XO/CW Unilin is an innovative partial fill cavity wall insulation system incorporating robust textured aluminium foil-facing on both sides and engineered jointing details. Xtroliner XO/CW improves U-Values and meets Future Homes standards, providing an excellent choice for passive and low en..
  • 80mm Unilin XO/CW T&G Insulation Board for Partial Fill Cavity Walls
  • Xtroliner XO/CW improves U-Values and meets Future Homes standards
  • XO/CW Providing an excellent choice for passive and low energy builds
  • Can achieve a passive U-Value of 0.15 W/m2K in a traditional cavity wall
  • Lambda (thermal conductivity) of 0.021 W/mK and Euroclass C s2 d0 fire class
£ 123.00
Ex Tax:£ 102.50
Estimated delivery: 5-7 working days