Soffatts dripping water

[Simon]

My kitchen roof is a reasonably flat angled tiled roof with two Velux windows fitted. The tiles are Marley and according to the roofer are suited to prevent water being drawn back through capiliary action due to the shallow angle of the roof. There is no leakage through the roof evident, but each time it rains, the soffatt at the bottom of the roof takes on water and drips for some time afterwards. The Velux windows were seated by the roofer on an additional area of roofing lead, but I noted that the tiles cut on either side of the windows are not sealed with mortar. The roofer told me that this was not necessary, but due to the dripping soffatt I am wondering whether water is getting underneath and filling the soffatt, and if so, whether I would be best to get some mortar each side of the Velux windows where the tiles start? Can someone advise?

[Simon Stroud]

I'm not 100% sure as my Velux windows were fitted by the people who did my loft conversion, but I vaguely remember that they include a surprisingly big "surround" that is hidden by the tiles and has a very carefully designed system to ensure that any water running down the sides of the window subsequently is diverted out on top of the row of tiles below the window and then on down the roof.

The loft converters were bodgers of the highest order, but at least this is one aspect that they seem to have done OK - no leaks in about 6 years.

... and no there is no mortar sealing the tiles. There is a "foamy" bit of the Velux surround that the goes under the tiles up the sides - I have just reached out and had a quick feel.

Maybe your extra-low-pitch roof needs things to be done in a special way?

Regards, Simon.

[dg]

The most likely cause of dripping off the soffit/fascia is rotten or inadeqate felt draping into the gutter - this lets water drip between the gutter and the fascia.

Even if the velux is letting in water, the water should run down the felt and into the gutter.

Check the eaves for this before looking at anything else

In any case, veluxes do not need any mortar around them

dg

[Simon]

Thanks for the advice - I`ll take another look before I make a mess with mortar Cheers

[The Natural Philosopher]

Felt should never be used to in anyway waterproof.

The normal thing if letting anything into a tile roof is flashing that runs under and over the tiles (soakers) ..or right over all the tiles in a single run..so that it leads water out on top of the tiles..soakers are a sort of series of fake right angle tile pieces interleaved with the tiles..

[keith_765]

Check to see if the alloy apron under the bottom tiles either side as been turned back on its self. The alloy sides are above the corrugated lead under the first tiles at the side. Which Marley tile is it ? Most low pitch tiles require extra head lap, 100mm 22.5 degs and lower. The lowest Marley tiles go down to is 17.5 degs.