Old concrete roof tiles. Damp on underside help! :-(

dave82_2

We have an old house with a concrete tile roof. The roof looks fine although a little weathered.

In the loft there is no backing to the roof just the tiles so you can see the underside.

After the downpour yesterday i had a look in the loft to check for any leeks.

There were no areas where any water was pouring in but there were several areas where the tiles join that were damp to the touch.

Is it normal for water to penetrate beneith tiles or am I looking at a new roof :-(

savemoney

Concrete is porous I believe although how porous I am not sure

Houses I have lived in never have had felt underneath the tiles/slate. Some councils houses at back of me roofs look fine but getting new roofs nonetheless are having inuslation (kingspan) and blue plastic sheeting underneath the wood.

dave82_2

Cheers not to worries about the fact there is no felt. Just want to know if anyone knows if seeing some dampness is normal or not :-(

vaio

Heavy rain, wind in the wrong direction and a bit of capillary action on the tile lap could well make it look a bit damp in places.

As long as it’s not actually dripping I’d not be too worried although if it dates from a time when felt wasn’t used the tiles could be approaching the end of their life.

The only cure is to remove all the tiles & battens, fit felt and new battens and then either relay the old tiles or (more likely) fit new tiles all of which is not a trivial matter

dave82_2

Cheers. I will keep an eye on it and start saving for a new roof!

aboard_epsilon

i thought all concrete roof tiles were laid with felt under them.

if not then correct me .

all the best.markj

vaio

I think under-felt became standard in the '70s so roof that doesn't have it is getting on for 50 years old (which i think is also the quoted life of concrete tiles)

My roof is slate and dates from 1860, no felt and the slates are fine and will see me out. Shame the same can't be said for the nails

aboard_epsilon

My house is 1954 ..has clay fired tiles and has felt underlay ..roof has never been replaced.

So must have been one of the first ones to have felt
..it also has as original plasterboard ceilings..and a couple of breeze block walls...all other internal walls are brick.

They must have been breaking new ground with it.

It had steel windows art deco style, when i first bought it, which were well rotten..now its got hard wood double glazing.

I've been here 27 years .


all the best.markj

knowloads

Around 1949 felt was introduced, the damp is either condensation from inside, or as mentioned porous concrete, some formun memebrs have made over 170 pages of comments regarding roof coating (see Aquashield) but cleaning before coating is a no no on unfelted roofs. Consider a re-roof and felt (breathable membrane these days), new battons and your good for 50 years.