FR/BGM

Specification Clause

The flat roof insulation shall be Unilin Insulation Thin-R FR-BGM _ _ _mm thick manufactured to EN 13165 by Unilin Insulation comprising of a rigid Polyisocyanurate (PIR) core between fleece finished bitumen/glass fibre facings with a Agrément declared Lambda value as low as 0.024 W/mK. The flat roof insulation shall be installed in accordance with instructions issued by Unilin Insulation.

Refer to NBS clause J42 420, J42 10.

Falls

The fall on a flat roof should be designed to ensure that rainfall does not pond

Fire Performance

The fire rating, when tested to TS 1187 and classified to EN 13501-5, will be dependent upon the waterproofing system specified.

Loadings

The boards are suitable for use on roof decks that are subject to limited maintenance foot traffic. Walkways should be provided on roofs requiring regular pedestrian access. When the roof is complete, protective boarding should be laid if additional site work is to be carried out.

Roof Finish

Built up roofing systems should be finished with a suitable reflective layer such as chippings. Advice should be sought from system manufacturer

Vapour Control Layer (VCL)

Decks should be primed before the application of the hot bitumen used to bond the vapour control layer. Reference should be made to BS 8217 when applying the vapour control layer. Carry the VCL past the insulation and seal with the parapet wall.

Laying (Timber Deck)

On plywood decks, Unilin FR/BGM should be fully bedded in hot bitumen over a continuous vapour control layer which has been nailed or bonded to the deck. The boards can also be mechanically fixed or the mineral coated glassfibre facer (MG) can be adhered with other suitable adhesive. Fixing heads should be sealed with bitumen.

Laying (Concrete Deck)

Ensure concrete decks are laid to provide correct falls to outlets and are clean, dry, without projections. Primer should be laid in accordance with the manufacturer’s instructions. The vapour control layer should be fully bonded to the deck and the Unilin FR/BGM should be laid into hot bitumen on the vapour control layer in a break bonded pattern. The boards can also be mechanically fixed or the mineral coated glassfibre facer (MG) can be adhered with other suitable adhesive. Fixing heads should be sealed with bitumen.

Bitumen Based Built Up Roofing Systems

Technical guidance from the appropriate bitumen waterproofing manufacturer should be sought as to assure proper installation of the bonded built up roofing system.

Fixings

The specification for fixing Unilin roof boards will vary with the location, roof height/width and topographical data. Architectural specification should be consulted. Generally with 1200mm x 600mm boards, a minimum of 4 fixings per board are adequate, located between 50mm and 150mm from all edges, additional fixings may be placed along the centre line. Counter sunk washers, 50mm in diameter should be used with each fixing. However, BS 6399 Part 2 or BS EN 1991- 1.4: 2005 + A1: 2010 (National Annex to Eurocode 1.Actions on structures. General Actions. Wind Actions) should always be consulted. It is recommended to seek advice from the fixing manufacturer for specific guidance. During the construction process, the construction should be protected from rain penetration during breaks in the process

Fire

Each project should be assessed for suitability of torch on applications. The suitability of materials, substrates and specifications should be assessed before commencement. Application of the torch on system should be undertaken only by fully trained personnel with appropriate fire precautions and fire extinguishing equipment available at hand. All timber roof components, and most insulation materials are combustible, and will be vulnerable to a naked flame. These materials may be hidden from view. Due attention should be given and all precautions taken. This is the responsibility of the operatives.