The advantages of PIR

As the brand leader within the UK’s largest category of insulation, Celotex PIR (polyisocyanurate) insulation provides one of the most cost effective, thermally efficient insulation solutions to the UK construction market.

What Is Celotex PIR insulation?
Celotex PIR is made by blending together two primary chemicals and other materials to form a rigid foam product. The heat generated during the reaction enable gases to evaporate and become trapped within cells delivering premium thermal performance characteristics.

Celotex insulation boards are manufactured via a continuous production process combining PIR foam between two layers of facer. The facer of the products will differ depending on the end use application. Celotex facers include aluminium foil, mineral glass tissue and other aluminium facers.

Why Is Celotex PIR Better Than Other Insulants?
Celotex PIR carries numerous advantages over other insulation materials used within the construction industry. PIR delivers significant thermal advantages compared to other typical insulation materials as well as being available in a wide range of product thicknesses and suitable for nearly all typical building applications.

Combined with a low environmental impact, enhanced fire performance, structural strength and moisture resistance, the specification of Celotex PIR insulation will deliver a higher level of insulation performance to any building project.

Celotex Thermal Performance
The main advantage of PIR insulation is its low thermal conductivity (lambda) value. Whilst the typical lambda value of PIR is 0.023W/mK, Celotex combining breakthrough technology and industry advancement now offers an improved thermal performance to 0.021W/mK on its FR5000, CG5000 and SL5000 products. This enhancement in product performance helps achieve better U-values and thinner solutions. Celotex PIR is up to 100% more thermally efficient than typical glasswool.

Low Emissivity
Celotex products are faced with aluminium foil facers which have been independently tested and approved by third party test houses. In applications where a cavity air space is present such as a partial-fill cavity wall, this means within the U-value calculation you can claim a higher thermal value for the airspace. In some instances, this can result in 5-10mm less insulation being required.

Multiple Applications
Celotex PIR insulation is suitable for use within pitched roofs where the insulation can be installed in various combinations between, under and/or over the rafters. In flat roofs, Celotex provides solutions compatible with most weatherproofing systems and installation techniques including single-ply membranes, mastic asphalt, bitumen and torch-on. For walls, Celotex can be used in either cavity or solid walls including masonry, timber frame and rainscreen cladding systems. Celotex provides solutions for floors where the insulation is laid below the concrete slab or as part of a beam and block, suspended timber or concrete soffit floor.

Celotex also provides an excellent option for thermal laminates where composite materials such as plywood, plasterboard and calcium silicate can be laminated to the product to deliver a ‘two in one’ solution.

Thickness Range
From as thin as 12mm right through to 200mm thick, Celotex PIR is available in a thickness range unrivalled by any other PIR provider. This provides additional choice and value for the specifier and end user.

Environmental Impact
The environmental impact of insulation materials are independently rated within the BRE Green Guide 2008. Materials are rated on an A+ to E scale where an A+ rating is given to materials with the lowest environmental impact. PIR insulation is generically rated ‘A’ providing a lower environmental impact than extruded polystyrene and some cellulose glass and stonewool solutions.

Celotex was the first manufacturer of PIR insulation to achieve an A+ rating when compared to the BRE Green Guide 2008 which it has held since July 2008. This A+ rating is driven via a BRE Approved Environmental Profile providing an environmental impact rating which is 20% better than typical PIR.

Fire Performance
PIR insulation is manufactured through an irreversible chemical reaction. This means that it cannot melt. The ratio of the two primary chemicals used to make PIR delivers a stronger chemical giving the product an improved resistance to higher temperatures.

With fire performance being an important selection consideration for many projects, Celotex is the only PIR manufacturer that has a Class O rated product in its range. FR5000 and CG5000 offer Class O fire performance throughout the entire product unlike phenolic insulation which has only had the foam tested.

Moisture Resistance
Water absorption through exposure to moisture or indeed in exceptional circumstances through floods, is a significant factor in the selection of any modern insulation. The thermal performance of mineral wools and phenolic foams is significantly compromised and reduced when exposed to water. Celotex due to having a closed cell structure is a hydrophobic product meaning it does not absorb water. This allows the thermal performance and integrity of the product to be retained over time.

Structural Strength & Weight
PIR insulation possesses substantial inherent structural strength. This is why Celotex is used so widely in the construction sector. The core prevents the product from sagging through time ensuring it retains its thermal characteristics. In addition the products can cope with light foot traffic or loading which is an important consideration in flooring and flat roofing applications.

These characteristics are complemented by the lightweight attributes of the product ensuring it can be easily handled and transported during installation. Based on 100mm product, Celotex PIR is over 10% lighter than phenolic insulation.

Life Expectancy
As Celotex products do not sag, absorb moisture or be permeated by air, you can be confident of consistent performance which will typically last the full lifetime of the building. There is also no requirement for additional maintenance or treatment to the Celotex boards during this time.