Triflex Kemperol and Self Terminating FlashingsSteven Dickinson
Just found your website and have a quick question regarding the use of triflex/widopan – from the look of your website this seems very similar to Kemperol that you describe in your videos?
Can you confirm whether (in order to meet building regs) lead flashing is required over the top of the up stands? I noticed in a video you used the term ‘self terminate’? Also, should the ‘fleece’ be cut into the wall as you would normally see with lead flashing?
On one of your videos you have chosen to cut back the wall and then render over the up stands? Is this recommended best practice or simply a ‘tidier’ finish?
Thanks for the email Phil,
Interesting as it’s an argument I’ve had with lots of manufacturers as at the end of the day its the roofing company that has to pick up the pieces if all goes wrong.
Surveyors and architects expect to see a cover flashing or sometimes called a slip flashing traditionally used to terminate up-stands of flat roofs against vertical surfaces. Some manufacturers argue that there roofing systems are self terminating and a flashing is not needed. This leaves the roofer and building control in a bit of a gray area as it’s all down to personal preferences.
We now nearly always place a flashing over the top. As regards the video with us placing the membrane into the wall we are using liquid plastic, again this has become controversial although with liquid plastic I think this works. Traditional felt or asphalt would crack and fall away because of the weight of the product having an overlapping flashing that’s not fixed and can slip back and forth with movement helps stop the cracking an excellent method of termination.
Liquid roofing systems such as Kemper Triflex and Liquid Plastic all soak into the wall are flexible and lightweight water cannot get behind as there is no behind the system is part of the wall, theoretically no need for a flashing.
If the wall is not that good we will flash over the top or build the system into the wall, we also flash over the top a lot just to keep surveyors happy as it’s still a details that looks like it should be there. We now don’t do Kemper Triflex or Liquid Plastic mainly because of cost mostly because of the health and safety problems, we much prefer Gacoroof and SD650 from 3M and where possible we will use EPDM rubber.