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A Guide to Celotex Insulation ....

What is Celotex Insulation ?

Celotex is a multi-purpose insulation board that can be used for a huge range of applications. Roof insulation , floor insulation , wall insulation and cavity wall insulation are places where Celotex could be used.

celotex insulation roof insulation

What is Celotex made from ?

Celotex Insulation boards are made using a PIR ( polyisocyanurate ) foam material. This foam is sandwiched between 2 layers of low emmissive foil. This creates a rigid foam core insulation board which is both lightweight and hard wearing. The production process is zero ozone depletion and as such has a low impact on the environment. At the time of writing Celotex PIR insulation is manufactured in thicknesses from 20mm up to 200mm.

Is Celotex waterproof ?

Celotex is moisture resistant as it is a closed cell foam product. This insulant is ok left outside for a small period of time but should not be left immersed in water as eventually this will break down the foam.

Is Celotex hard wearing ?

By nature of this product it is relatively easily chipped and snapped during transit but once installed is a strong durable insulation that should not break down if installed in the correct way and situation.

Is Celotex fireproof ?

At the time of writing there is no fireproof PIR insulation available on the market. However Celotex is fire resistant which means the material slows the spread of fire. Specifically designed to resist high temperatures with a Euroclass 'F' reaction to fire classification.

Is it easy to cut Celotex insulation ?

Cutting Celotex insulation is easy using a fine tooth saw. It must be noted if not using a fine tooth saw this will cause disruption to the edge of the board and not make it easy to get a proper seal around the edge when installed. We have also known people use sharp bread knives to saw through some of the thinner sizes

What is the thermal conductivity of Celotex?

A standard Celotex insulation board has a thermal conductivity of 0.022W/mK. This thermal conductivity can be used to calculate the products required to achieve a target 'U' Value in your construction.

What lifespan does celotex Have ?

Celotex PIR insulation boards if left undisturbed have an approximate lifespan of around 60 years. Importantly this is about 3 times the suggested lifespan of fibreglass insulation.

How to store PIR insulation ?

Celotex PIR insulation boards should be stored flat so as not to encourage the board to bow. Although these boards are moisture proof they should not be allowed to sit in water so raising from the ground is important where water is present. There are no real other issues with storage of this type of insulation.

What can Celotex be used for ?

A general purpose insulant Celotex can be used in many applications. These include Floating and underscreed floors, Cold and warm roof situations, cavity wall between inner and outer skins, and internal wall projects. Ideal for use in both commercial and residential insulation builds.

Do I need to use foil tape with Celotex ?

Creating a proper thermal envelope when building is important. As such all the joints where boards meet should be sealed with an appropriate aluminium foil tape. This foil insulation tape is much easier to use at 100mm as it provides a proper seal.

Celotex Floor insulation

When considering your floor insulation installation Celotex should be one of the first prodcuts you look at. This can be the perfect solution for both under screed and concrete floors along with floating timber floors. When installing Celotex PIR it should always be fitted tight together and the joints taped as to create the perfect seal. The floor is one of the largest areas in your property that will transfer cold and Celotex can help prevent this happening.

Celotex board is the ideal insulation when installing underfloor heating as it has the additional benefit of having a grid pattern on the board.This grid pattern makes it much easier for pipe layout.

The Following Insulation boards can be used as floor insulation...

Celotex GA4000

Celotex TB4000

for further information please see our Celotex insulation page

Celotex Wall insulation Boards

Insulating walls with Celotex is easy and can be done in a number of ways these include

Cavity Wall insulation in between the inner and outer skins of the construction.

Exterior walls on the inside of the inner skin of an exterior wall.

Internal partition walls in between the plasterboard layers.

Cavity Wall insulation

Celotex cavity wall insulation , can be either partial fill or full fill. Partial filling a cavity is where the insulation is installed leaving a 50mm airspcae in the cavity allowing it to breath. Celotex CW4000 is an ideal product for partial fill cavity wall construction. Full fill cavity boards are generally trongue and grooved to ensure a airtight seal and fill the cavity all bar a few millimetres. Thermoclass '21' is the celotex insulation answer for full fill cavity wall projects.

Internal Stud Wall insulation

Celotex GA4000 can be an excellent insulant for internal partition walls. These boards should be cut to fit in between the wall studs and then covered with the appropriate plasterboard finish. This type of wall construction gives a high thermal and fire resistance on any internal stud partion wall.

External Wall insulation

Celotex can be an ideal insulation for fixing to the inner skin of an external wall, GA4000 would usually be used for this or quite often Celotex PL4000 which is a pre bonded plasterboard to Celotex insulation. This pre bonded board can help save time on installation as it is a 2 in 1 product.

The Following Insulation boards can be used as internal and external wall insulation...

Celotex XR4000

Celotex TB4000

Celotex PL4000

For further information please see our Celotex insulation sales page

Building with Celotex for roof insulation.

Roof insulation can be applied in a variety of ways and help very much with the energy efficiency of the building. Various types of roof insulation include.

Loft floor insulation

Pitched roof insulation both over and under rafter

Flat roof insulation

Using celotex as an insulant in a loft floor.

Insulating your loft floor is one of the easiest and most effective ways to save on household bills and increase energy efficiency. This can be done in a number of ways. The insulation board can be cut to fit between the joists thus allowing for boarding over the top and being available for use as a room or storage. alternatively it can be laid across the top of the joists allowing for a layer of fibreglass to be installed in between. It must be noted that when installing in between allowance must be made for light fittings so that they do not overheat. Importantly when laying over the top of the joists , these boards are not designed for load bearing in this situation and should not be used as storage or foot traffic.

Insulating a pitched roof with Celotex.

PIR insulation is an ideal insulant for use in the pitch of a roof. This is because not only is it a great insulant but also very easy to cut and install. Both cold and warm roof insulation projects can be achieved using celotex, Meaning the board can be installed in both over and under rafters along with inbetween where necessary.

Insulating a flat roof with Celotex insulation.

Celotex boards can make insulating a flat roof very easy with the range of celotex available on the market this can be done in both over joist and in between joist applications. A layer of Celotex PL4000 could also be used under the joists to ensure a complete thermal envelope. A Flat roof can be the source of great heat loss in your property so insulating properly is a must.

Roof insulation from Celotex can be from the following ranges....

Celotex GA4000

Celotex XR4000

This is a guide to Celotex insulation

Where can I buy Celotex Insulation ?

For all your insulation requirements give Direct insulation online store a look where you can save money on all the Celotex Insulation range. Or call the national sales office on 01793 791010.


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