Neighbour replaced slate roof but we now have a leak
Anonymous user 15/03/2024 - 2.44 PM
I live in a mid terrace 1910 ish house, we have a slate roof, about a year ago the neighbour had their roof completely replaced still using slates. The house the other side of them also has a slate roof. The issue is where their roof joins ours ( and also their other neighbour) there is a very distinct ridge about a metre wide. The tiles in these areas have a very lifted appearance, which causes rain to get in.I have been told by the neighbour that when the battens were replaced they used 25mm (where as the ones in my roof and his other neighbour are the original presumably less thick battens hence the ridge due to height difference). Was there a better option for joining the roofs? What should they have done?
Are you a tradesperson and able to answer this question?
With any roof in a terraced run, whether slate or tiled the rise between each property is common but sadly a plausible remedy can be made when a re roof is carried out by a considerate roofer. The party walls are the stop point between each property and over the years of natural expectancy the rafters shrink and give in to the weight of a roof. When a roofer installs new felt and Barton's a level line from party walls should be made and the Baton's packed up to take out the dip in the timbers, then the slate lone will run true to your side, how ever remember that you're side will dip from this point so a roofers job becomes limited when then tying in to yours without being liable for damage to your side.
It sounds very much like they haven’t successfully lapped the membrane below the slate. The only way water should get below the slate is to be “wind driven”, the membrane below is the failsafe in this instance. Stripping the slate off to check this will be time consuming and costly. You may first, using a “black light” on the membrane below, see if you can see if the water is tracking from elsewhere.
Overlap on the underfelt could be an issue (if yours has any felt that is) but the roofer should have checked the thickness of adjoining properties roof battens if yours are too thin to accommodate the new tile then a bonding gutter should have been used. If, as another tradesmen said previously, the new roof has a ‘dipping’ appearance then he should have packed out the old rafters to give a flat appearance. Either way I would be asking the roofer to come back, I don’t like to criticise others work without seeing it but it does ‘SOUND’ like something hasn’t been done propefly
Hi, at best guess without looking I suspect your roof will have 3/4 inch x 1.5 inch batton and the new roof would have 1 inch x 2 inch. There's not a lot of difference, but if the battons are butted up it causes a kick when slates are put in place and what can make the kick worse is if the new battons go beyond the partition wall.
