Kingspan TR27

TR27 is a roofing insulation board from the Kingspan Thermaroof range of innovative insulation products. It features a polyisocyanurate (PIR) core, which is sandwiched between two glass tissue facings. The board is designed for use in flat roofs with compatible waterproofing systems. Contact Kingspan to confirm whether your roof’s waterproofing system is compatible with TR27.

You can buy genuine TR27 insulated roof panels online directly from Insulation Wholesale. We sell a wide range of Kingspan TR27 PIR boards in multiple thicknesses that fit flat roof insulation work. We offer trade pricing and fast dispatch for UK-wide delivery.

To install TR27 boards systematically beneath your waterproof layer:

1.Prepare the deck 

Ensure the roof deck is clean, dry, and smooth. Any irregularities can cause problems later.

2. Fix a vapour control layer (VCL) if required

Check the design notes. Some flat roof systems require a VCL on warm roofs to keep moisture from moving into the insulation. VCL use depends on roof build-up and internal humidity.

3.Lay out the TR27 boards

Position the PIR boards butt tight (edges touching) across the roof area. Start at one corner and keep rows straight. Boards typically come 1200 × 1200mm.

4.Fasten or bond the board

The fixing method depends on the waterproofing system. TR27 boards are typically:

• Mechanically fixed – Use approved insulation fasteners through the boards into the deck, following the membrane manufacturer’s fixing pattern.
• Bonded – Use system-approved PU adhesive to bond boards where specified.
• Loose-laid with ballast, depending on the membrane spec.

5.Check board levels

Confirm boards are level and fully supported, with all edges aligned. Uneven boards can cause ponding later.

6.Seal joints if required

Taping joints is not always required for TR27. Use compatible tape at board edges where required by the roof specification or membrane manufacturer.

7.Apply a waterproof layer

Once the boards are secure, install your waterproofing system (single-ply membrane, liquid-applied, mastic asphalt) over the insulation.

In the UK market, the major brands supplying TR27-style flat roof insulation boards are:

• Kingspan (Thermaroof TR27) – Only Kingspan makes “TR27”, the PIR flat roof board with fibre-free core and coated glass tissue facings.
• Recticel (Powerdeck F / Powerdeck U) – Comparable PIR insulation boards that match TR27 thermal and mechanical performance.
• Ecotherm (Inno-Bond) – PIR flat roof boards designed for bonded and mechanically fixed systems. Manufactured to similar TR27 performance levels and often interchangeable in spec.

These product lines deliver rigid PIR insulation with low thermal conductivity (~0.024–0.027 W/m·K) and good compressive strength for flat roof conditions.