Celotex General Purpose PIR Insulation Board - TB4020

Name: Celotex General Purpose PIR Insulation Board - TB4020
Brand: Celotex
SKU: ybsueqd7uh
Availability: InStock

The Celotex TB4020 General Purpose Board is a versatile polyisocyanurate (PIR) insulation board th...

Best current price£17.40from Brick Superstore

Best offers

Shopping.co.uk recommended and popular offers

Lowest price

Brick Superstore£17.40Visit shop

Celotex Light/Green Tb4025 General Purpose Pir Insulation Board - 2400 X 1200 X 25Mm

Visit shop

All Offers

3 offers from £17.40 - £33.46

View price history by clicking the chart icon.

Brick SuperstoreCelotex Light/Green Tb4025 General Purpose Pir Insulation Board - 2400 X 1200 X 25Mm

£72.00 delivery

£17.40

Visit shop

Travis PerkinsCelotex Grey PIR TB4000 Insulation Board, 25x2400x1200mm

£30.00 delivery

£33.46

Visit shop

Product Information

Full details

The Celotex TB4020 is a high-performance polyisocyanurate (PIR) insulation board designed for contractors and homeowners seeking to improve thermal efficiency in walls, floors, and roofs. Its standout feature is an impressive 0.022 W/mK thermal conductivity, which allows for thinner insulation profiles while meeting strict energy regulations; however, users should note that as a rigid foam board, it requires precise measuring and cutting to ensure a tight, bridge-free fit during installation.

All features

Model Part Number	TB4020
Brand	Celotex

Extended Product Information

FAQs

What is the thickness of this board?

The TB4020 model is exactly 20mm thick.

Can this be used on floors?

Yes, it is suitable for floor applications, provided it is laid on a flat, even surface.

Do I need to leave an air gap?

While it functions as insulation regardless, the low emissivity foil performs best when positioned next to an enclosed air space.

Is the board moisture resistant?

The foil facing acts as a vapor control layer, but the board should not be used in standing water or persistently damp environments.

How do I cut the boards safely?

Use a fine-tooth saw or an insulation knife in a well-ventilated area, wearing protective goggles and a dust mask.

Troubleshooting

Board is difficult to fit between uneven joists

Use a sharp insulation saw to shave thin layers off the edge rather than trying to force the board into place.

Gaps between boards after installation

Fill small gaps with expanding foam insulation and cover joints with high-quality foil tape to ensure a continuous thermal barrier.

Pros and Cons

Pros

High thermal efficiency in a slim 20mm profile
Lightweight construction facilitates easy handling
BBA certification ensures building regulation compliance
Reflective foil facing improves performance in air cavities

Cons

Rigid board material is not flexible for curved surfaces
Requires precise cutting tools to avoid gaps
20mm thickness may require multiple layers for deep insulation needs

Setup, Compatibility & Care

To install, measure your wall or floor area and cut the board using a fine-toothed saw or a sharp insulation knife. Ensure boards are tightly butted together to prevent thermal bridging—gaps allow heat to escape and moisture to build up. For best results, tape the joints using a dedicated foil tape to maintain the integrity of the vapor control layer.

Compatibility: The boards work well with timber frame and masonry structures. When storing, keep the boards in a cool, dry place, ideally off the ground, and protect them from prolonged exposure to direct sunlight or moisture during the construction phase.