A reader's Roofs and roofing question: smoke hood?

Brian T.   from   Hervey Bay, Country: Australia   had this smoke hood question.

Bill's reply

Hi Brian, Look up "Dektite", they make all sorts of flashing for around pipes. I have just had a quick look and they do a "square base" one up to 440mm. Only thing I would worry about is the temperature, will the EPDM rubber last?

Probably the best way is to get a flashing made up at a sheet metal shop out of Zincalume. They do it all the time for commercial kitchen extractors etc.

At the same time I would then fix a soaker flashing from under the ridge to just past half way down your pipe, like on the solar tube photo on my flashings page.

If you use any sort of sealer I'd say use Sikaflex PU, unless the sheet metal shop know of a better one for handling higher temperatures.