Protrusions such as pipes and ducts should be adequately flashed where they pass through the sheeting surface. Where profile sheeting has to be cut away, to avoid anything seeping through, additional framing should be installed as required to support the sheeting.
Depending on the position of the cut, special attention should be given to back flashing the sheeting to the ridge or point of water entry up the roof from the protrusion.
In all cases, all cutting and flashings should be so arranged that adequate provision is made for the drainage of all troughs and corrugations.
Depending on the type of protrusion you have, (e.g velux windows have their own flashings kit, hot or cold pipes you can use a dektite) you may wish to check with the manufacturer for any flashings kit that is made for your requirements.
How do I Handle Protrusions?
When protrusions are a part of your roofing process, you’ll need to make sure you install adequate flashing and additional framing, where required, to support the sheeting. Depending on the position of the cut through the roof, special attention should be given to roof flashings for pipes, in particular, vent pipes.
Flashings are placed around vents, skylights and plumbing pipes, among other roof protrusions, and are usually made from galvanised steel or any other rust-resistant metal. Occasionally, flashings can be made from plastic, rubber or roofing felt.
In all cases, all cuttings to make way for protrusions and roof flashings should be so arranged that adequate provision is made for the drainage of all throughs and corrugations. As above, please contact the manufacturer for flashings kit.
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