External Corner Cavity Full Fill Wall PIR Insulation 150mm

Product Description

Unilin (previously Xtratherm) CavityTherm is a continuous wall insulation system. It delivers ultimate thermal performance with the added assurance of inbuilt protection from wind driven rain.

It is a high performance composite board of enhanced PIR with a lambda value of 0.021 W/mK, for full fill cavity wall applications. CavityTherm has gas tight facings with one face bonded to a profiled HIPS skin during manufacture to provide a drainage plane. The total coverage provided by this pack is 2.16m2.

Unilin (previously Xtratherm) CavityTherm key features:

• Engineered HIPs facer provides wind driven rain protection
• Moisture redirected to outer surface
• Prepositioned slots for sloping wall ties – no creep
• Fully engineered jointing
• Full range of accessory pieces build continuous system
• Excellent Thermal Bridging Values
• Continuous insulation layer
• Minimal cavity width requirement
• No need for engineer’s report
• Ultimate U-values & meets standards
• See the Product Brochure and Installation Guide here
• See the Agrément Certificate here
• See the Specification Clause here
• See the Declaration of Performance here
• If you require very large quantities then you can call us on 0818 888 000 or open up the live chat on our website and we can provide a seperate quotation for very large quantities.
• Thermal conductivity is 0.021 W/m²·k (BS EN 13165:2008)

Unilin (previously Xtratherm) is a built-in insulation system that achieves ultimate U-values within traditional wall constructions. It doesn’t require an engineer’s report, meaning that minimal heat energy is lost through the walls.

Meeting A+ or Passive standards within a 100mm cavity width, CavityTherm builds as a system to provide a continuous insulation layer that you can see is installed accurately. It provides an affordable and practical solution when looking to buy best performance wall insulation.

CavityTherm’s unique engineered profiled facing directs any moisture that might penetrate the external wall down the protective facing and back onto the external leaf, giving added protection from wind driven rain. The board includes specifically designed rebated edge detailing on all four edges to allow the system to tightly interlock when installed. This engineered jointing of the insulation layer ensures continuity and results in excellent thermal bridging detailing.

CavityTherm’s unique engineered profiled facing directs any moisture that might penetrate the external wall down the protective facing and back onto the external leaf, giving added protection from wind driven rain.

The board includes specifically designed rebated edge detailing on all four edges to allow the system to tightly interlock when installed. This engineered jointing of the insulation layer, with the addition of bespoke ancillary pieces to insulate effectively around services such as hockey sticks, meter boxes and corner details, ensures continuity and results in excellent thermal bridging detailing.

Typical Physical Characteristics:

• Density 30 kg/m3
• Compressive Strength >100 kPa @ 10%
• Thermal Conductivity 0.021 W/mk
• Service Temperature -20 degrees C to +100 degrees C

The profile edge of the boards allows wall ties to be positioned sloped down to the outer skin, whilst acting as a template for mortar on the inner skin. Unilin (previously Xtratherm) CavityTherm has gas tight facings – with one additional face bonded to provide a drainage plane, directing moisture onto the outer leaf.

Unilin (previously Xtratherm) CavityTherm’s specially designed profile maintains a residual channel, protecting the structure. Installing Unilin (previously Xtratherm) CavityTherm gives U-Values that are indicative of targets set to achieve the higher levels of the Code for Sustainable Homes – but within traditional construction allowing the architect to design low carbon homes and maintain an overall cavity width of 100mm.

Frequently asked questions:

What is CavityTherm?
Unilin (previously Xtratherm) CavityTherm wall insulation board is a high performance composite board of PIR core with a lambda value of 0.021 W/mK. The boards have gas tight facings with one face bonded to a profiled HIPS skin during manufacture to provide a drainage plane. CavityTherm’s unique profiled facing directs any moisture that might have penetrated the external wall down the protective facing and back onto the external leaf. The board includes specifically designed rebated edge detailing on all four edges to allow the system to tightly interlock when installed.

What is the real benefit of using CavityTherm?
Put simply, the U-Values achieved by placing CavityTherm into your standard 150mm cavity meets the Passive House standards for Ireland. It builds as a ‘system to ensure continuity. You can physically see that the procedures on site are being followed. It’s a very practical, affordable solution to low energy design.

What wall ties do I use with CavityTherm?
Standard S/S wire wall ties are used with CavityTherm. At up to 5 ties/m2  the thermal impact is negligible because the cavity is kept to a reasonable width. Pushing the cavity wider and adding greater amounts of insulation will necessitate low conductivity ties, and result in worse thermal bridging at junctions. It is for this reason that a U-Value of around 0.15W/ m2K is seen as optimum by regulations.

Why slope the wall ties down to the outer face?
This is not specific to CavityTherm, all wall ties in any construction should slope slightly down to prevent water travelling along the wall ties into the construction. Wall ties must be kept clean and free of mortar.

What thicknesses of CavityTherm are available?
CavityTherm is manufactured for 100mm,125mm and 150mm cavities, and achieves U-Values as low as to 0.12 W/m2K.

What building types can use CavityTherm?
CavityTherm can be used in new external masonry cavity walls up to 25m in height in domestic and non-domestic buildings.

CavityTherm has a lot of accessories as part of the ‘system’, what are they for?
An excellent wall U-Value is not the only item that must be addressed to achieve a Low Carbon Fabric. Airtightness and thermal bridging must also be improved. Thermal Bridging is in fact just ‘good detailing’ and is accounted for in SAP. Xtratherm is the only insulation board manufacturer that addresses gaps or breaks within the continuity of the insulation layer.

How do you detail insulation around stepped cavity trays, periscope vents in suspended floors or at corners, or meter boxes?
Unilin (previously Xtratherm) has developed bespoke insulated pieces to ensure that these details are well insulated so as to avoid thermal bridging and possible condensation mould growth.

Is there a benefit in the ‘Engineered edge detail’?
The Building Regulations now ask that insulation systems be ‘continuous’ and are installed in accordance with accredited detailing. The jointing system in Unilin (previously Xtratherm) products achieves this, encourages a more accurate build, and avoids the 0.01 U-Value penalty that should be applied when calculating to BR443.

When a board is cut what tape do I use to make the join?
When two abutting boards are to join, cut the profiled edge from each board and ensure that they are closely butted. The joint should be sealed. When building the inner leaf first – seal with a waterproof tape. The tape should be applied to a dry surface. When building from the inside a preparatory self adhesive jointing strip is available to insert over the join. Any penetrations or small repairs can be made with the tape or sealant. Any services running through the insulation layer should be sloped to the outside. DPCs should be dressed over services as per Eurocode 6.

You recommend the use of a ‘Cavity Board’ – what is that?
The use of a cavity board is recommended during construction. It is a board that is placed over the installed boards as the inner leaf is raised to catch any mortar drops that might fall. If mortar does fall onto the upper edge of the CavityTherm the HIPS skin is easily cleaned with a damp cloth.

If you need any help with this Unilin (previously Xtratherm) Cavity Fill solution then just call our helpful and friendly team today on 0818 888 000 or open up the live chat and we will help in every way we can.

• Note: Delivery of this bulky product is available Nationwide but will be subject to a bulk delivery charge. Delivery charges are calculated during checkout according to the delivery address provided.

Should you require very large volumes of this product then we may be able to improve your delivery charge. To discuss this you can call us on 0818 888 000 for more information and to confirm pricing.