Help! We have a flat roof kitchen extension on the back of our house. The main house is rendered the extension isn't. The render where the flat roof meets the back wall has blown and fallen off meaning the roof flashing has come loose and away from the wall leaving a gap and a leaking roof. We asked a roofer we have used before to come fix the roof as it was pouring in when it rained but he said the whole back needs re-rendering first and then he can fix new led flashing into the render. My husband was then left to chisel out mortar from the brick work level with the roof line and fix the roof back to the wall and use roof sealant to try and patch it up over christmas. So my question is, as I've read conflicting advise, do we have the lead flashing fixes into the brick work and render down to it. Or do we have the render done first and then a groove ground into it and the lead flashing fixed into it? And is there anyone who does roofing and rendering who could do both jobs at once?
Are you a tradesperson and able to answer this question?
Chase out the brick work where the lead goes as deep as possible take the old lead out I prefer to put a sealant in the joint first then the new lead or a theft free lead in then you can re point the joint then get it Re render then get it rendered with a qualified plaster Good luck with the job.
Answered9 February 2020
2
Anonymous user
Hard to answer without seeing the job but I would hack the old render, cut a deep groove into the wall (sloping slightly upwards) - ideally min 40mm deep - but the deeper the better. Ideally 150mm above the roof. Dress the lead into the groove, fix and seal. Then fix a stainless bell bead just above the groove and render down to the new bead. The only reason to render first is if the condition of the wall is so poor that you cannot cut a groove into it. In this circumstance I would prep and apply a first coat of render then follow the above procedure. So to answer your question. Roofer first then render. A competent plasterer should be able to do all this work. Does not need a roofer.
Personally i would remove all lose render, chase the wall for the lead flashing have that done the seal it up then I'd render down to the lead or maybe just over it as an extra layer of protection, personally I think they need to be done at the same time
Answered9 February 2020
0
Anonymous user
First
Fit the lead into the brick joint
Then render the wall down to the lead
Regards
sorry your roofer was a bit useless , lead should always be channeled into the mortar lines & sealed even when rendering this stops any water getting behind the render creating water ingress into the property
good luck Alex
