It is the responsibility of the installer to ensure that the flue installation through the roof is weatherproof i e no rain must ingress into dwelling roof space.
Flue installation through tiled roof.
Page 10 page 11.
The flue pipe must not rely on the roof terminal for support.
Google roof pipe flashings for products and install info.
With the pipe in a vertical position trace around the pipe using a pencil.
Hi welcome back to cover that roof.
The flue must rise high enough to create a 2 3m horizontal clearance between the top of the last length of pipe and the surface of the roof.
The penetration will be oval to have a round pipe exit vertically through a pitched roof you need an oval hole in the roof.
Most installers or roofing contractors will use a slate piece or a metal or lead piece that fits onto a flat or pitched roof with a gromit where the flue pipe goes through.
This is the conclusion of the 2nd of a 2 part video series showing the installation of a kitchen vent flashing.
Go into your attic.
Take it up through the soffit remove a roof tile and use a tile slate pipe flashing to exit pipe through and seal.
Use reducer adaptors for varing pipe diameters.
Position the vent pipe up to the bottom of the roof.
For an internal twin wall system rising up through the roof surface you must consider all four of the following building regulation requirements.
Use a flexi metal connector to take up any misalignment.
You may need an experienced roofing contractor.
This flashing is used to provide a weatherproof seal where the flue passes through a tiled or slate roof.
However depending on your type of roof a flat roof for example your engineer may also get a roofing contractor to check everything is properly sealed.