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Example: Felt Flat Roof Porch Manchester

Replacement Felt Flat Roof

A repair/replacement flat roof on a front porch in Manchester, UK

K-Roofing contractors inspected a leaking flat roof on a small domestic porch. Minor repairs were unsuitable because the roof survey had identified rot in the timber decking caused by water ingress and damp that could not be mended.

• The defective plywood roof deck, felt membranes and chippings were stripped back to reveal sound roof joists. These old materials were removed from site and disposed of

• To fix the drainage problems and ponding we mechanically fixed 'firring pieces' (triangular wedges 3" to 0") to the joists. This ensured a fall to the new timber deck allowing rainwater to drain off
• We installed 18mm Exterior Grade WBP (Weather and Boil Proof) plywood decking. This has water resistant adhesives used in its construction to ensure water resistance and combat any damp
• At brick wall abutments (where the roof meets the wall) we installed 50mm x 50mm 'tilt fillets' to ensure drainage. Tilt fillets are 3 edged raised wooden upstands that channel rain water from roof edges towards the front gutter
• The porch roof specification was agreed with the client: a built-up felt membrane system. The merits being the suitability to roof type, use, local environment, lifetime and cost of materials and installation
• We applied replacement roofing felts in layers using the 'Torch-on' system. 'Torching on' is ideal for small roofs because the bitumen on the reverse of the felt turns liquid when heated and bonds the felts together. The result is an impermeable water barrier with total lap security and long life
• Fire precautions are always taken because direct heat is applied to the materials.
• We replaced the timber fascias with uPVC fascias (horizontal) for long, low maintenance life
• To the edges we supplied and installed aluminium metal edged trims
• We replaced the existing guttering with uPVC gutters and down pipes
• At the wall abutment a 150mm Lead substitute / alternative (UBI-Flex) flashing are installed and mechanically plugged at 300mm centres, a final finish/seal is provided using a flexible lead sealant. This ensures a watertight fix
• The client was delighted with the quality and cost of the repairs and we installed roof facia and nbarge boards to the pitched roof of the main building