TORCH ON ROOF INSULATION

Torch-on roof insulation such as PIR is a high performance board for use in warm flat roofs with hot-applied waterproofing systems (including torch-on) and any bitumen compatible single-ply membrane system. Its optimum stability, strength and structural integrity, allows for the flattest finish. In fact, torch on roof insulation is often associated with 120mm PIR insulation called Kingspan Thermaroof TR24, TR27 or 120mm Celotex flat roof insulation. There is a strong reason for that. Market leader - Kingspan are the first insulation manufacturers who achieved a Grade B listing to LPS 1181: 2003: Part 1 for a built-up external flat roof system. Kingspan® Thermaroof TR26, TR27, Thermataper TT46 and TT47 are the first insulation products to carry this rating. Kingspan® Insulation's Thermaroof and Thermataper ranges will also provide an extremely high level of thermal efficiency, achieving or exceeding required U-values with minimal thickness. These boards offer unprecedented resistance to mechanical stress (compressive strength 120kPa-150kPa) and  extra resistance to weather conditions. In combination with plywood and a waterproof system, they are absolutely the winner and not replaceable in torch on applications. On other hand Celotex TC3000 Flat Roof Board and its PIR foam core is temperature tolerant and withstands the application of hot bitumen to the surface temperature of 240°C. Board has a thermal conductivity of 0.025 W/mK and it is inert and stable in water and soil. However, the most used product is the FR/BGM Xtratherm Thin-R PIR Flat Roof Insulation Board. Its black side suit most bituminous waterproofing systems and lighter side suit fully adhered single ply membranes. Some contractors are saying it’s perfect for the job and probably the only board you'll need.

TORCH ON INSULATION PRODUCTS

KINGSPAN TR27

Kingspan Therma TR27 is used for flat roofs waterproofed with a fully adhered single ply, mastic asphalt and cold liquid applied waterproofing. 

Cost: 100mm - 36.35 per m2
AVAILABLE THICKNESSES: 25mm | 50mm | 60mm | 80mm | 90mm | 100mm | 110mm | 120mm | 130mm | 140mm | 150mm | 160mm 
Thermal conductivity (λ-value): 0.024 - 0.027 W/mK

KINGSPAN® THERMAROOF TR26

Kingspan Thermaroof™ TR26 LPC/FM is suitable for use with most mechanically fixed PVC single–ply waterproofing membranes. This durable product has a thermal conductivity of 0.022 W/mK and  is perfect for the flat roofs waterproofed with partially bonded built-up felt, fully adhered single-ply, mastic asphalt and cold liquid applied waterproofing.

Cost: 100mm - 36.99 per m2
AVAILABLE THICKNESSES: 25mm | 50mm | 60mm | 70mm | 80mm | 90mm | 100mm | 105mm | 110mm | 140mm | 150mm 
Thermal conductivity (λ-value): 0.022 W/mK

KINGSPAN® THERMAROOF TR24

Kingspan Thermaroof TR24 is manufactured with Nilflam technology which means trademarked set of formulations based on polyisocyanurate (PIR) manufacturing processes, which is a prime factor behind the exceptional performance of these rigid urethane flat roof insulation products.

Cost: £24.70/m2
AVAILABLE THICKNESSES: 80mm | 100mm | 120mm | 130mm | 140mm | 150mm 
Thermal conductivity (λ-value): 0.024 - 0.027 W/mK

XTRATHERM® FR/BGM

Xtratherm PIR insulation board with bitumen glass fibre and mineral glass facing is designed for partially bonded, torched-on and built-up bituminous felt systems. Xtratherm Flat Roof Thin-R board can also be used in mechanically fastened or loose laid ballasted bituminous roofing systems.

Cost: 100mm - £32.58 per m2
AVAILABLE THICKNESSES: 25mm | 30mm | 40mm | 50mm | 60mm | 70mm | 80mm | 90mm | 100mm | 120mm | 130mm | 140mm | 150mm 
Thermal conductivity (λ-value): 0.026W/mK

CELOTEX® TC3000 (discontinued)

Celotex TC3000 is suitable for use in hot applied bituminous systems and mastic asphalting and torch-on systems.

PROTHERM® PIR TORCH

ProTherm PIR B Tapered is a rigid Polyisocyanurate (PIR) foam core faced with bitumen coated glassfibre tissue on one side and polypropylene fleece on the other. Individual ProTherm PIR TORCH tapered boards should be laid with the bitumen tissue side up with edges butted and in a break bond pattern laid at right angles to the edges of the roof or diagonally across the roof.

Cost: 100mm - £28.60 per m2
AVAILABLE THICKNESSES: 30mm | 50mm | 60mm | 70mm | 80mm | 90mm | 100mm | 110mm | 120mm | 130mm | 140mm | 150mm
Thermal conductivity (λ-value):  30 to 80mm = 0.026 W/mK, 80 to 120mm = 0.025 W/mK, 120 to 150mm = 0.024 W/mK

ECOTHERM® ECO TORCH PIR 

Designed for use with hot applied roofing systems or adhered single ply systems.

Cost: 100mm - £27.38 per m2
AVAILABLE THICKNESSES: 30mm | 50mm | 80mm | 100mm | 130mm | 140mm 
Thermal conductivity (λ-value): 0.026W/mK

RECTICEL POWERDECK® U

Its optimum stability, strength and structural integrity allows for the flattest finish.
AVAILABLE THICKNESSES: 30mm | 40mm | 50mm | 60mm | 70mm | 80mm | 90mm | 100mm | 120mm | 130mm | 140mm | 150mm 
Thermal conductivity (λ-value): 0.024 - 0.026 W/mK

TORCH ON INSULATION BOARD DETAILS

Most popular torch on insulation board thickness used for flat roof application is 120mm. The typical length and width of a torch on PIR board is 1200mm x 600mm and is available in most popular thicknesses from the manufacturer such as Kingspan, Celotex, Xtartherm, Recticel or Ecotherm.
Torch on insulation range includes the following readily available product thicknesses: 25mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 110mm, 120mm, 130mm, 140mm and 150mm.
When deciding which board to use, the density of a block is often the most important factor. The product is classified based on compressive strength and compressive stress. Compressive strength determines what the grade of PIR is. In fact, it is the maximum uniaxial compressive stress that material can bear before fracturing. Number is assigned to the PIR product based on its compressive stress at 10% compression. Torch on rigid panels are designed to cover all general needs for thermal insulation, fire resistance and sound reduction and because of their versatility and high compressive strength 120kPa, PIR boards are often used in roofing jobs.

TORCH ON SYSTEM INSTALLATION

Torch on application is recommended to be used on flat roofs as it involves heating the stripes on the upper surface of the vapour control layer to disperse the thermofusible film and activate the bitumen stripes. The boards are positioned onto the vapour control layer and pressed into the surface ensuring a good and uniform bond. Boards must be close butted and laid staggered (broken joints) and should be laid with the black facing side up. On metal decks the long edges should be laid at right angles to the corrugations. All board joints should be fully supported by the deck. When applying PIR torch on existing bituminous or sanded substrate the surface must be prepared in accordance with the project specific guidelines.

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