125mm Unilin Rafterlock Variable Width Pitched Roof PIR Board - Thin-R XT/RLOC - 1200mm x 370mm
125mm Unilin Rafterlock Variable Width Pitched Roof PIR Board - Thin-R XT/RLOC - 1200mm x 370mm
- Product Code: A1-6693
- Delivery Time: 7 - 10 days
- Brand: Unilin (prev. Xtratherm) (Tech. support: 03712221055)
- Model: 1200mm x 370mm - 0.44m2
Our ratings on 28-08-2026:

4.8 out of 5
125mm Unilin Rafterlock Variable Width Pitched Roof PIR Board - Thin-R XT/RLOC - 1200mm x 370mm
Length: 1200mm
Width: 370mm
Thickness: 125mm
Pack Quantity: 1
Board coverage: 0.44m2
Thermal Conductivity: 0.023W/mK
R-Value: 5.4m2K/W
125mm Unilin Rafterlock Thin-R XT/RLOC is a high‑performance pitched roof insulation board comprising a rigid Polyisocyanurate (PIR) core between low emissivity foil facings. Its unique variable‑width design ensures a snug fit between rafters, delivering excellent thermal efficiency with reduced installation time and waste. Unilin Rafterloc Thin-R XT/RLOC Pitched Roof Board offers a specification‑ready solution for pitched roof insulation, combining flexibility, efficiency, and compliance in one product. It is particularly well‑suited to projects requiring tight fitting insulation with minimal waste and rapid installation.

CHARACTERISTICS
- Designed for sloped/raftered roof constructions
- Variable width pitched roof insulation board
- Rigid PIR insulation with low emissivity foil facings
- 20–30 mm width variation for tight fitting between rafters
- Flexible adjustment margin eliminates gaps and thermal bridging
- PIR core with foil facings achieves high U‑values, supporting compliance with Building Regulations
- Width variation minimises off‑cuts and improves material utilisation
- Tight fit between rafters reduces fitting time compared with standard boards
- Provides consistent insulation quality across pitched roof systems
- Reduces labour time and material wastage
- Ensures a continuous insulation layer with minimal thermal bridging
- Variable width feature adapts to site conditions and rafter spacing
APPLICATION
- Ideal for pitched roof insulation where efficiency and compliance are critical.
- Suitable for upgrading roof insulation without extensive structural alteration.
- Helps achieve improved thermal performance in line with current regulations.
INSTALLATION
- Position boards between rafters with foil facings exposed as specified.
- Adjust the variable‑width edges to achieve a snug fit against rafters.
- Ensure boards are flush with rafter faces to maintain a continuous insulation layer.
- Stagger board joints to avoid continuous thermal bridges.
- Leave a small expansion gap (typically 2–3 mm) at abutments if recommended.
- Seal perimeter joints and service penetrations with approved tape or sealant to maintain airtightness.
- Overlay with plasterboard or internal lining as specified.
- Ensure vapour control layers are correctly positioned if required by the design.
CERTIFICATION
- ISO 9001:2015+A1:2024 - Quality Management Systems
- ISO 14001:2015+A1:2024 - Environmental Management Systems
Brand: Unilin (prev. Xtratherm)
Model: 1200mm x 1200mm - 4.32m2
Delivery Time: 3 - 5 days
140mm Unilin FR/MG is a high performance PIR core with mineral coated glass facers suitable for use below single ply waterproofing systems and partially bonded built-up felt. It is compatible with adhesively bonded single ply roofing membranes laid on mechanically fixed ..
Guide Price: £148.54
£178.25 inc VAT
Brand: Unilin (prev. Xtratherm)
Model: 1200x2400mm - 8.64m2
Delivery Time: 1-3 working days
125mm Unilin Thin-R Hyfloor XT/HYF is a high performance floor Insulation board with superior thickness to performance ratio allowing the lower targets required under the new Building Regulations to be achieved with minimum thicknesses. Unilin Thin-R Hyfloor XT/HYF is a high performance foil faced P..
Brand: Unilin (prev. Xtratherm)
Model: 2400mm x 1200mm - 8.64m2
Delivery Time: 7 - 10 days
130mm Unilin Safe-R 019/MA (Roofs) is a high‑performance phenolic insulation board designed specifically for warm roof applications where exceptional thermal efficiency is required with minimal added build‑up. Its advanced phenolic core delivers one of the lowest thermal conductivities available in ..
Brand: Unilin (prev. Xtratherm)
Model: 2400mm x 1200mm - 2.88m2
Delivery Time: 1-3 working days
130mm Unilin Thin-r XT/PR-UF has a core of polyisocyanurate (PIR) bonded to low emissivity textured aluminium foil facings. Unilin XT/PR-UF board offers excellent insulation performance with excellent thermal conductivity. Unilin XT/PR-UF is CFC & HCFC free and is manufactured under the hig..
Guide Price: £63.52
£76.22 inc VAT
Brand: Unilin (prev. Xtratherm)
Model: 1200mm x 2400mm - 2.88m2
Delivery Time: 1-3 working days
59.5mm Unilin Thin-R Thermal Liner XT/TL-MF is a composite insulated panel of 50mm Unilin PIR core with foil faces bonded to 9.5mm tapered edge plasterboard for mechanically fixing to internal walls. Unilin XT/TL-MF is designed to provide high levels of thermal insulation and dry lining in one opera..
Guide Price: £53.30
£63.96 inc VAT
Brand: Unilin (prev. Xtratherm)
Model: 1200mm x 2400mm - 2.88m2
Delivery Time: 1-3 working days
92.5mm Unilin XT/TL Thermal Liner Dot and Dab Insulated Plasterboard is a high performance rigid insulation board made from 80mm Unilin PIR core faced with composite kraft paper bonded to 12.5mm plasterboard, specially designed for internal walls dry lining and insulation, due to its closed cell com..
Guide Price: £62.39
£74.87 inc VAT











