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125mm Kingspan Kooltherm Cavity Closers (pack of 10)

125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
  • 125mm Kingspan Kooltherm® Cavity Closer (KKCC 125)
  • Premium performance uPVC insulated cavity closer
  • Designed for closing cavities around masonry wall openings
  • Thermal conductivity of 0.022 W/mK - 2400mm lengths
  • Suitable for use in both new build and refurbishment projects
Estimated delivery:
In Stock
£ 328.80
Ex VAT: £ 274.00
  • Brand: Kingspan®
  • Model: 125mm KKCC Cavity Closer
  • Weight: 14.88kg
  • Dimensions: 2,400mm x 170mm x 125mm
  • SKU: KKCC 125
  • Product code: P1-2587
  • MPN: 125mm KKCC Cavity Closer

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Kingspan Kooltherm Cavity Closer 125mm (KKCC 125) is an extrusion of PVCU with a premium performance fibre-free rigid thermoset phenolic core designed for closing cavities around masonry wall openings in England and Wales.

Cavity Closer Kingspan Kooltherm is compatible with uPVC, timber, metal and composite window frames, suitable for use in both new build and refurbishment projects.

It provides a simple and efficient method of closing cavities around openings in masonry cavity walls, and has a thermal conductivity as low as 0.022 W/mK.

The thermally efficient insulation core inhibits heat transfer and thus reduces thermal bridging, whilst the uPVC casing provides a damp proof barrier.

Kingspan Kooltherm® Cavity Closer can reduce the risk of condensation forming at reveals and thus unsightly mould growth, which can lead to the deterioration of plaster, paintwork and wallpaper.

Using this premium performance cavity closers you will avoid problems commonly associated with the use of traditional methods for the closing of cavities.

Kingspan Cavity Closer provides a simple and highly effective method for closing cavities around openings in masonry cavity wall constructions in England and Wales.

The insulation component of the product shall be manufactured with a blowing agent that has zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP).

KKCC Cavity Closer comes in 2400mm lengths, 125mm thickness is designed to fit 125mm cavities.




Thickness: 125mm 

Width: 170mm

Length: 2400mm

Thermal Conductivity: 0.022W/mK

Compressive Strength: 100kPa

Water vapour resistivity: 300MN.s/g.m

Fire Rating (Reaction to Fire): C(Class 1)


Kingspan Kooltherm® Cavity Closer KKCC Features:

 · Thermal conductivity of 0.022 W/mK.

 · Unaffected by air-infiltration.

 · Easy to handle and install.

 · Non-deleterious material.

 · For use in England and Wales only.

 · Simple and efficient method of closing cavities.

 · Premium performance fibre-free rigid thermoset phenolic core.

 · Simplified SAP calculations - bespoke set of psi-values for jamb and sill details valid for a broad range of constructions.

 · Inhibited heat transfer - reduces thermal bridging, condensation risk and mould growth.

 · Weather resistant - forms an integral DPC.

 · Can be fitted with door and window frames as a combined unit.

 · Insulation core manufactured with a blowing agent that has zero ODP and low GWP.


Cavity Closer Kingspan Kooltherm® Installation:

 · Cutting should be carried out using a fine toothed saw in such a manner that cross-sectional cuts are square.

 · Plaster or floor screed is applied directly to Kingspan Kooltherm® Cavity Closer as the section provides an effective key.

 · Where it is used in conjunction with a floor screed at a door threshold, the screed should be of sufficient thickness(65mm minimum) or reinforced to prevent cracking.

 · Plastering, the first coat of plaster should be pricked up into the keys on the Kingspan Kooltherm® Cavity Closer and then scored as a key for the next coat of plaster.

 · Dry-lining, the dabs for dry lining readily key into the Kingspan Kooltherm® Cavity Closer Fixing Oversailing Window Boards.

 · Window boards should be fixed in the conventional manner.

 · Direct fixing to Kingspan Kooltherm® Cavity Closer is insufficient.

 · Where an embedded tiled inner sill or threshold is required, the Kingspan Kooltherm® Cavity Closer profile provides a key for cement bedding.

 · On completion, the frame is sealed to the surrounding masonry and internal plaster in accordance with normal practice.

 · Kingspan Kooltherm® Cavity Closer is non-loadbearing and should not be used to support window or door frames, nor used in place of normal cavity wall ties.

 · Care must be taken when storing to prevent distortion of the sections.

 · Kingspan Kooltherm® Cavity Closer should not be exposed to excessive heat.

 · The packaging of Kingspan Kooltherm® Cavity Closer should not be considered adequate for outdoor protection.

 · Ideally, sections should be stored inside a building.

 · If, however, outdoor storage cannot be avoided, then the sections should be stacked clear of the ground and covered with a polythene sheet or weatherproof tarpaulin.

 · Sections where the insulation core has been allowed to get wet should not be used.

 · Kingspan Insulation products are chemically inert and safe to use.


*Further information may be found in our Downloads section.

Fairly easy access to all PDF files.

Datasheet ǀ Declaration of Performance - DoP ǀ BBA Certificate ǀ Installation Guide ǀ Certificates ǀ Brochure ǀ SPEC Sheet 

*Special Product - Non returnable cancelable.

Colour Light shade of red
Compressive Strength 100kPa
Length 2400mm
lmetres 24.00
Material PVCu J-section with a phenolic insulation core
Pack Quantity 10 lengths
Profile J-section uPVC
Size 125mm x 170mm x 2400mm
Thermal Conductivity 0.022 W/mK
Thickness 125mm
Weight 14.88kg
Width 170mm
Coverage 2.4 linear meter per one length
Finish PVCu profile
Application Temperature from +5 °C to +25 °C
Shipping method Articulated Vehicle ǀ Courier
Applications Closing cavities around masonry wall openings
ETA Notification Yes
Features Inhibits heat transfer and reduces thermal bridging
Manufacturer Kingspan Kooltherm® KKCC

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We deliver insulation materials to Mainland UK only. Deliveries to Highlands, Northern Ireland, Isle of Wight etc.. might be possible at additional cost.
We offer free delivery on most of the orders above £300 (excluding VAT) (except special products - shipping cost via courier - products marked ''Request A Quote'')

Delivery of some insulation materials might be extended due to the current situation (Covid-19, stock shortages, allocations).
If you need materials quickly please contact us - we will do our best to help you source materials needed.

We do not deliver on weekends and bank holidays. Sometimes we can deliver on Saturdays - please check with us before placing the order.
If you need any further information please contact us tel. 02081910776

We can help to calculate price per m2 or linear meter (one meter in length) cost, please just contact us via phone 02081910776, email or live chat. Alternatively, you can work it out yourself quickly and easily: to get cost per meter square please divide price shown in orange area by ''Required area (m2)'' Example price of £28.80 divided by board coverage 2.88m2 = cost of £10.00 per m2.


No matter whether you choose a local installer or a national company, there’s a few tips to help you find the right installer for your home insulation improvements, such as asking for recommendations and making sure that they’re part of a certification scheme. This makes sure that they have the right skills and standards of workmanship to carry out the installation, and you can be sure that they know exactly what they are doing.


1. Thermal inspection picture in portfolio

It’s worth seeing a installer’s previous work. There’s no harm asking if you can see any properties nearby that they’ve installed insulation in. Best way would be to see Infrared Thermal Imaging Inspections. Thermal cameras spot small, but key changes in temperature in different areas of a house, identifying problematic areas that the human eye never could and some that a visual inspection could only hypothesize.

2. Reviews

Along with checking recommendations and previous work, finding reviews online can often be a great way to find out if they provide a good service or not. However, it’s best not to solely rely on reviews you may find or review websites, as there’s no controlling who writes them.

3. Compare prices

Comparing prices will also ensure companies can’t take advantage of you and give you a fair price. 

4. Word of Mouth

The best way to find a great insulation installer is through recommendations. Make sure you ask friends and family. They will most likely give you their honest opinion and can tell you from first hand experience.


Whether you require a wall, cladding, external wall, loft or floor insulation fitted, you can find and hire your local insulation installers from popular UK web pages. A simple internet search will return thousands of potential installers near your area.



We are the stockist of construction materials and related products for both trade and DIY from most recognizable brands in the UK like Cordek, RCM, Promat, Rockwool, Isover, Celotex, Xtratherm, Ursa, Low-E, Cedral, Kingspan, Dufaylite, British Gypsum, K-rend, Ecotherm, Iko enertherm, Kay-Metzeler, Terrawool to allow you to complete your insulation job on time at competitive prices and the highest standards.


Whether you are a large company or a DIYer, if you need a large amount of insulation materials, we can offer quantity discounts at the best prices. Please contact us and our friendly customer service will try to find the best and cheapest solutions for you. We value your time and we will try to deliver the products as soon as possible at a reasonable price to your construction site or house. The UK's leading insulation supplier near you and your needs. Price List available upon request.
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
125mm Kingspan Kooltherm Cavity Closers (pack of 10)
£ 328.80