Leaky Roof

[chiangrai]

I have a new roof on 2 small rooms and it's leaking already.

It has a very slight slope,only 10 degrees and has large concrete tiles.6mm thick and crimped(corrugated).

The Thai guys have put long screws with hex heads and metal washers with a rubber ring on the inside.

That's where it's leaking.It's coming in under the screws.

What do I do....take them out and put silicone under them or something.

And what tool do I use,it would be so slow using a spanner(wrench).

Something that would fit on my impact driver would be good

[lopburi3]

They have a paint material that can be used to cover such - but suspect you will have problems with water build up and blowing up to top of tiles and entry there which will be much more serious unless it is sealed (normally they just have an extension on wall above tile which would still allow water to be blown up and under).

Edit: as said above washer should be on top of tile and compressed to prevent leakage - on the inside of the screw but on topside of the tile. Tiles should be fit tight together.

Edited May 3, 2016 by lopburi3

[Pib]

Strange, you really shouldn't have to do nothing....shouldn't have any leaks at those screw points if they were installed properly and were the proper size. As long as the screws where installed on the ridges of the roof tiles, where installed "straight in" (not slanted), the holes for the screws were not made too big (screws should just barely fit into the tile holes (assuming they used self tapping screws this shouldn't be a problem), rubber washer pressing against the tile, and the screws were tightened snuggly you shouldn't have any leaks.

You should go with roof tar-like material they make for such leaks...silicone probably wouldn't hold up/stick well under constant hot sun after a year or so.

And are you sure the leak is at the screw points as water leaks can be very deceiving as to their true source/beginning unless you actually see the leak while it is occurring/the water intrusion occurring real time and tracing it to the very beginning point. Good luck.

Edited May 3, 2016 by Pib

[aussiandrew]

With the heavy rain that regularly occurs in the wet season a roof slope of only 10 degrees sorry to say really is asking for long term major leaking problems. Your builder did not do you any favours. You may have to get the spray in insulation to permanent fix this problem.

Edited May 3, 2016 by aussiandrew

[buythisdashcam]

Is true that when a roof is leaking the only solution is often to rebuilt it completely ? Small repairs will never be definitive ?

And why all these houses are similar, nobody has any idea to build something different ? Why not adding a second roof or a giant sail on top of the standard roof ?

[lopburi3]

Leaks can be fixed - there should not be any need to rebuild roof.

[Goanna]

The minimum angle for cpac monier tiles, at least like the popular ones that I have used, is 17 degrees. This is to minimise rain blowing up inside. Have a look on the suppliers website for specs. Nw, you may need to silastic every joint.

[Goanna]

Actually, your post is confusing. You cannot have concrete tiles of .6 mm. Must be steel panels.vastly different.

[Goanna]

2x

Edited May 4, 2016 by Goanna

[lopburi3]

Do not believe poster has CPAC tiles if measured in mm (CPAC are very thick/small tiles). Believe he is using the normal tile below.

[keeniau96]

Small roof pitch eg. 10 degrees, and wind blowing at the roof is very likely to result in rain inflow. I have that situation over the kitchen wing and at times it is a real nuisance, tried many cures (cement the gas with silicon etc), place metal sheet layer under the times, redo fasteners ... nothing really works well.

edit: sticky keys

Edited May 4, 2016 by keeniau96

[chiangrai]

I wrote this post when I saw water coming in when I was inside and

could see water coming in where the screws were.

I had never actually got the ladder out and looked at the screws from the outside.

I've just done that now and the screws are loose.They are not fully tight and the

washer isn't fully tightened down on the tile.

How did this happen.The roof was done 9 months ago.Could there have been setleling

or something like that or did the boys just not tighten the screws.

So I should tighten them all up and wait for the next big shower I suppose.If they still leak then I will have to do something else.

The screws have been put into the ridges of the tiles,the rubber ring is on the outside,they are self tapping screws,it all looks fine except the screws are not tight

[Pib]

Tighten them down and get out the water hose to test...no need to wait for rain (which could be a long wait with the current drought). Good luck.

[sipi]

Don't over tighten them. Those cement tiles can form hairline cracks which will also leak. Then the tiles will need to be replaced.

[lopburi3]

But they need to be tight - I suspect they had the drill too short and did not drill set hole deep enough so stopped turning screw when it got too hard - you may have to re-drill if on wood beams. It metal and screw not too long perhaps they drilled too large a hole and you will not be able to make tight without larger screws.

Cement tile can last a very long time if properly installed - our house roof is still original from 40 years ago.

Edited May 4, 2016 by lopburi3

[chiangrai]

I've just tried to tighten the screws up.

The first one was broken and just left there.

The second one goes down through the first part of the box iron,

(is that what there called,the lengths of rectangular metal that he used instead of

roofing timbers)but doesn't penetrate the other side.

The third one tightened but it was put in crooked so the rubber ring is not flush

on the roof.

The expression "pay peanuts,get monkeys"comes to mind.

I don't know what to do,the whole house is probably like that.

I might have to put each screw in a different place and patch up the old holes.

[Pib]

Those rubber washers will indeed last a long time....my MIL's roof is built as such, it's at least 3 decades old, and don't leak...probably a couple hundred such screws used to hold down her roof tiles like shown in lopburi3's #12 post above. The screws are screwed into wood supports (very hard wood); not metal. And I got personal with her roof when installing a C band antenna/black dish on roof a few years ago and needing to temporarily remove/reinstall some of the tiles and screws to accomplish the installation.

[chiangrai]

So what about the screws that go into the box metal and don't come out the other side.

How do I tighten them.It will need to be at speed with an impact driver.

I would prefer to drill a pilot hole but I would need a drill bit long enough to go from the ridge of the tile down through the box metal.Can I get a 3mm drill bit that long.

Or I need to get an 8mm socket from eBay.but I'm afraid of splitting the tiles when the screw head is that close to the tile.

In the mean time my wife has stuck blue-tack to the inside of the tiles around the screws

and they have stopped leaking.A Thai solution to a Thai problem.

Only a few screws were leaking even though they all look bad from the outside.

[Crossy]

The screws usually only go through one side of the box so no problem there.

Our main roof and the new patio roof extensions are held on with self-drilling screws (drill through the tile and the beam in one). This sort of thing http://www.screwfix.com/p/c-1022-steel-self-drilling-screws-5-5-x-38mm-100-pack/66798

The boys put them in with a regular electric drill, I don't recall seeing them nip them up with a spanner so that's how tight you need them (just compressing the washer).

As noted above, take care not to over-tighten as there's nothing underneath to stop you cracking the tile.

[chiangrai]

In my case the screws go through the first part of the box metal and go on to touch the inside of the second side of the box and stop.When they do this the head of the screw is nt touching the tile.

Sounds like they used screws that were too long.Do they come in different sizes.

[Crossy]

In my case the screws go through the first part of the box metal and go on to touch the inside of the second side of the box and stop.When they do this the head of the screw is nt touching the tile.

Sounds like they used screws that were too long.Do they come in different sizes.

It does indeed, yes you can get various lengths.

Take one out and get the next shorter one, they usually come in steps of 1/4".

[Pib]

They have many sizes at hardware stores....pretty low cost also.

Edited May 6, 2016 by Pib