Garage Roof

Good afternoon staff
I have a small water leak in the garage which is driving me crackers as I can't find the source of the leak. The roof is asbestos. The asbestos feels damp in places. Does asbestos become porous over the years?
Steve
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How many years?
This the time of year (mild days and frosty nights) when you might expect condensation on the underside of a single skin roof. Worse if the car is put away wet or the door left open during the day.
Cement bonded asbestos is supposed to be good as the porosity allows small amounts of condensation to be absorbed and then evaporated when things warm up. 30 year old stuff may be so porous the moisture is unable to evaporate before the next cycle starts. One clue is drips that form where purlins touch the underside.
Alternatively, cracks hidden under moss?

--
Tim Lamb

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writes

I don't really know. There is not a damp course. I would guess it has been there for a good 40 years.

Ahhhh yes. I have a habit of leaving the door open all day. The car won't fit into the garage due to all of my junk; sorry, tools and things :-)

No cracks that I can see. There is moss but I can't get to it.
Thanks.
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On 08/12/2012 15:14, Mr Pounder wrote:

In a word....yes.
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What can be done about this?
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If you can find an actual leak/crack, first drill a hole to stop it propagating. Then fix with Flashband. It needs to be dry/warm weather. Clean up with wire brush and use the black gunge primer first. Watch out for the dust, not good for you.
If porous (never had this problem), bitumous paint on the outside
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If you can find an actual leak/crack, first drill a hole to stop it propagating. Then fix with Flashband. It needs to be dry/warm weather. Clean up with wire brush and use the black gunge primer first. Watch out for the dust, not good for you.
If porous (never had this problem), bitumous paint on the outside
I can't find the leak! But re - Tim I have always had the door open. I have just discovered that the walls are wet. I have have sparked of my old dehumidifer which is reading 99% humidity.
Taa for the reply.
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On 08/12/2012 15:51, Mr Pounder wrote:

It's difficult to cover asbestos with bitumen etc once the asbestos is holding water like a sponge. Very difficult to dry it out completely. Get rid of the nasty stuff. Best to re-roof it and be done with it.
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I'm not paying for Paddy to shaft me up.
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Could be one of the roof fixings, especially if it only happens when it's windy. (Fixings are on the crest.) Asbestos cement lasts forever until some one walks on it and breaks it.
Get some drain dye & mix it up in a bucket with water. Pour on roof & go inside to see if/where dye appears.
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<<<Does asbestos become porous over the years>>>
Seems to - I used to walk on my garage roof 14 years ago, then I did so three years ago and fell straight through it so be warned!!
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Sadly one must first check that you are the same (or similar) weight that you were 14 years ago. ;-)
--
No plan survives contact with the enemy.
[Not even bunny]
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This is what I am afraid off.
I am quite a stupid person.
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On 08/12/2012 17:10, Murmansk wrote:

All the fibrous cement roofing panels become brittle over time so you should never walk on them.
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On Sat, 8 Dec 2012 09:10:06 -0800 (PST), Murmansk

Not to put 10 stones on?
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On Sat, 8 Dec 2012 15:14:22 -0000, "Mr Pounder"

Our corrugated asbestos garage roof is about 50 yrs old. The underside will get condensation on it on really frosty nights that can sometimes drip, but the usual cause of drips is via the nail holes. The black plastic seal thingies on the nail heads have gone hard over the years and no longer make a good seal, and leak when it rains heavily, even though they're through the crests of the ridges, not the valleys. The solution was to go over all the nail heads with black Unibond gutter-seal gunge applied generously. Crawling boards essential while on the roof. I used large sheets of plywood that I had spare.
--

Chris

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wrote:

Yes and thanks. The bloke next door has crawling boards but he don't like me too much. He is a cat man!
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A ladder with a plank of wood on the rungs makes a substitute. A suitably shaped garden hoe can be used to carefully hook out the moss from the valleys.

--
Tim Lamb

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