ChatterBank1 min ago
Roof
Got a broken roof tile been meaning to get it fixed we have had some nasty weather past few days so went in to loft to check noticed where broken tile is rain has come through the membrane this has not happened any other time it has rained could the gale force wind forced the water through it has always been dry till this bad spell of weather
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No best answer has yet been selected by col72. 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.Just a guess, col, but it's very unlikely to have water come through the felt.
What is very common though, especially in strong winds, is for water to be blown between the "lap".
i.e. where one layer of felt laps over the one below. Old felt widths were about 900mm (3'). Newer felts are around 15mm (5'). So there are plenty of laps.
I had one recently where I had to advise stripping the roof section and re-felting because the laps were only a few millimetres rather than the conventional 100mm (4").
Even with a proper 100mm lap, gales can occasionally lift the lap enough to let water blow in. It's often evident when the loft fills with snow.
What is very common though, especially in strong winds, is for water to be blown between the "lap".
i.e. where one layer of felt laps over the one below. Old felt widths were about 900mm (3'). Newer felts are around 15mm (5'). So there are plenty of laps.
I had one recently where I had to advise stripping the roof section and re-felting because the laps were only a few millimetres rather than the conventional 100mm (4").
Even with a proper 100mm lap, gales can occasionally lift the lap enough to let water blow in. It's often evident when the loft fills with snow.
Water travels along beams, col. It can show up some distance from the leak. Especially with the wind behind it.
Unless the membrane is torn, water won't get through it. I really can't think of any other reason, I'm afraid. Maybe you've lost, or dislodged a ridge tile?
Tiles or slates?
If tiles - concrete or clay?
Unless the membrane is torn, water won't get through it. I really can't think of any other reason, I'm afraid. Maybe you've lost, or dislodged a ridge tile?
Tiles or slates?
If tiles - concrete or clay?
If you're sure there is no tear at that spot, then there's one more possibility. If it's right on a rafter ....... then it sometimes happens that driven water will get in through the nail hole where the batten is nailed (through the felt).
I've had that before.
Old-fashioned bitumen felt or modern microweave?
I've had that before.
Old-fashioned bitumen felt or modern microweave?
Yep, that can happen, Boxers. I guess it's a nail hole. Old-fashioned bitumen felt was sort of self-sealing around a nail hole because of its soft, tarry nature.
Modern felts, although breathable and far superior, don't have that property.
It only comes to light when a tile is missing, and is subject to wind-driven rain.
Modern felts, although breathable and far superior, don't have that property.
It only comes to light when a tile is missing, and is subject to wind-driven rain.