If You Had A Twin, But Didn't Realise...
Family Life2 mins ago
The flat roof on our bay window has been leaking.
Having had roofers round to qoute on fixing this there have been 2 methods proposed. I have no idea which would be best. Can anybody help?
Current covering is a mixture of zinc and lead. The lead has a roll, or broomhandle as one guy called it, down the middle.
One option is to replace with code 5 lead with a plywood base underneath.
The other option is to flatten the existing lead and put in a scree.
To me the scree seems like a good idea as it would direct the water, but the fact that the lead has a roll in it would suggest that it is below the minimum code 5 so would flattening be the right thing?
Any thought would be most appreciated.
Thanks
No best answer has yet been selected by Bez. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.Forget the screed and flattening nonsense, and painting with bitument, it is rubbish.
The first thing is to know why it leaked. Is the rainwater outlet blocked? Is the outlet of the right size? Can all of the roof drain to it? Are there puddles? Did the water rise above the roll so that water got in through the lead welt which is on top of the roll? Does the roll stop the water from getting to the outlet? Has somebody nailed through the lead/zinc? Are there perforations or a hole? Are the flashings at least 6" high? This is the sort of investigation that you must carry out before you do anything at all. It may be that all that is required is a simple repair somewhere..
However. if it all has to be replaced there are two ways (1) replace it all with lead (do away with the zinc), or (2) replace it with a single sheet PVC covering (there are several sorts on the market, and so long as you go for a reputable system it is trouble free and lasts forever). You may have to strip whatever the existing lead is sitting on and replace it with (1" suggested) WBP ply (marine is not necessary) firred to give a decent fall to the outlet. If you would like amplification of the foregoing, can you post a photograph to assist?
Hi Golden Shred.
The outlet is very small. It is a late Victorian house with the original pipe, but the outlet is much smaller than even this original pipe.
The roll does impede the water reaching the outlet since it does not fully flatten out. (Also not helped by a join which faces the wrong way stopping the water).
Puddles do collect since it cannot reach the outlet and the outlet does not seem to be at the lowest level of the flat roof. I have not seen water go over the roll though.
The flashings have actually cracked the bath stone where it is attached at the top meaning that water can get into the stone itself.
Not sure how to post a picture, but if this description is not enough I will work out how to do it.
Cheers
Hello Bez. I really should see something of it before I comment further. Could you try www.tinypic.com? To use take pic, upload to My Pictures, go to Tinypic, press Browse, right click on picture, press Select, then press Host It on Tinypic. After picture arrives on Tinypic look to 3rd of the 4 addresses starting URL, left click so it turns blue, right click press Copy. Close Tinypic, come here on A/bank, put cursor at start of line, right click and press Paste. URL should be on A/bank in black, press keyboard Enter key and it will turn red and become a link.
I will look in again later tomorrow.