PIPE THROUGH A FLAT ROOF - KEEPING IT WATERTIGHT?

[K2harry]

Any advice please. I am about to run a 22mm copper pipe up through a flat roofed garage into the loft of a house. What is the best way to keep the roof weatherproof / water tight at the point of exit of the pipe.

Any help appreciated.

 

[justlead1]

Hi. If you are running any size pipe through a roof, flat or pitched it usual practice to weather it with a lead slate. This allows the pipe to move without creating stress / leak at the point of exit. You will find images of lead slates at http://www.justlead.co.uk

 

[K2harry]

Many thanks. as the pipe passes through the lead slate is that point just sealed with external mastic? And what about the lead slate, how is that 'sealed' to the roof - If it's placed on top of the felt what's preventing water ingress underneath and likewise if it's sited under the felt what's preventing water ingress?

Pitched roof no problems, tiles over the top of the slate at the top end with the slate over the tiles at the bottom, water just runs down. And with for example a flue, the flue vertical roof fittings are weatherproof so water won't run down the side of the flue into the roof.

 

[justlead1]

Hi. You normally scrape gravel of roof around area of lead slate, drill the hole for pipe and seal base of slate to flat roof material by using hot bitumen, torch on etc this will vary according to your roofing material. If this seams costly and you have facility why not take the pipe out through a wall and bend so as to avoid tampering with roof? Good Luck

 

[roofer1234]

this is an easy one cut the hole and depening on what roofing material it is put a lead or plastic sleeve around this then seal this to the flat using a ptch of torch on mineral faced cap sheet felt would take a felt 20 mins if that to install and then you can either use external mastic to seal the sleeve and the pipe or use a rubber joint to seal it. need any help with details or quotes then give me shout where do live anyway as i maybe able to help you for next to nothing.