Ask a Tradesman
Don't understand lead flashing!!
After all this wet windy weather we have noticed damp coming through on both sides of our house where the ceiling joins the wall. We have a loft conversion so it is quite obvious where the water is coming from. The roof itself looks in pretty good condition, I believe it is about 10 years old, however all round the edges the tin (lead?) flashing was not flat against the roof tiles at all - in some places pushed right up at 45 degrees! A handy friend hopped up there and hammered the flashing gently back down again so it was flush and indeed the problem seemed fixed. However another couple of months of wet windy weather later and water is coming through again.
I am not really sure I understand what the flashing should actually do - even flush with the tiles it would hardly form a water-tight seal. And should it be pliable enough that wet windy weather bends it out of shape?!
What work do you think we need done to fix this?
sounds to me that there may not be sufficient mortar/sealant on the chase line in the wall. also another problem that there maybe is the lap, which has already been mentioned previously. it may also be a factor that there has been stressing to the lead when it has been hit with a hammer. lead should be bossed gently with a wooden/plastic boss tool and not a steel hammer, although my theory is swaying more to the chase line. i get too many jobs where the mortar needs re-pointing and the lead needing resetting.
Answered 19th Mar 2014
without looking at the roof it is impossible to be 100% sure if it is the flashings that are causing the issues you are having.
the lead should not be pliable enough for the weather to move. this really sounds like the wrong code lead has been used or there is insufficient overlap onto the tiles/ brickwork to do it job sufficiently.
the lead used should be a code 4 lead which has a blue tape round it, if it had a green tape, this is a cheaper lead to thin to be used for flashings.
the flashing is to seal your roof and building where they join against the weather the over lap at least 75mm-100mm but depending on the type of roof tiles may require a bigger over lap.
best bet is post the job on the site and get a local expert round to assess the problem / solution / cost.
good luck Alex
Answered 3rd Mar 2014
I concur! It sounds like the lead used is probably code 3 and being blow up in the wind
Answered 3rd Mar 2014