Roof Leaks

[curtklay]

I think I've read all the posts about leaking roofs, but am more confused than ever on how to fix them.

My house is less than 2 years old with tile roofing, but they did not install foil under the tiles. When it rains, I can hear drops hitting the gypsum ceiling in various places, but have only seen small water spots appear in 2 locations. The water has yet to actually leak through the ceiling, and the spots dry up very quickly when the rain stops so it seems minor, but it's making me nervous and the dripping sound is very annoying. The builder has been out twice, patched, siliconed, and painted several locations, but to no avail. He even took a hose up on the roof and sprayed while a worker sat in the loft area. They said they found it, but nothing has changed. During the recent rains, I went up into the loft area myself, but could not see any sign of a leak from the tiles even when it was pouring. Everything was bone dry, which amazed me since I could still hear it and the water spots again formed on the ceiling. I have another "repairman" coming out to inspect, but am expecting more of the same, so I'm seeking feedback from TV members on the process of spraying foam on the undersides of the tiles, particularly the SPRAYME PURFOAM company. I've read a lot of previous posts, but it seems to be a very mixed bag. Some say it's great, others say it's horrid. IMHO, it looks like it could be a viable solution to a minor dripping problem. I do have ventilation areas in the roof so I don't think the heat build up that others have warned about would be a problem as long as the foam was not sprayed over them. I also don't think that puddling would be an issue since the leak is minor, and it seems to me the water would just get pushed back out from wherever it's coming in since the foam dries hard and thick. But I'm no expert on this. Actually, I thought the ideal solution would be to seal the tiles from the outside with a clearcoat spray, but whenever I get into that, all I get are blank stares.

So, I'm seeking some current advice from anyone who has recent experience with the spray foam on the inside, or anyone who has succesfully sealed the outside by another method. I am amazed that roof leaks are such a common problem in a country that receives so much rain. I'm also amazed that the most common fix is to put a bucket on the floor!

[Pib]

My house is about 4 years old, using the rippled tile that is about 17" long and 13" wide that I think you are talking about. The sides of each tile have grooves that allow it to interlock with the tile next to it and each tile overlaps the tile below it by about 4 inches. Each tile costs in the 10-20 baht range at hardware stores. Pretty common roof tiles for any house worth over a few million baht. I'm not talking the long, wide sheet tiles that are screwed down. I have foil underneath the tile roof, but that foil is really for insulation (heat reflection) rather than a second rain barrier. Well, the foil may act like a water barrier but the foil stops just before the gutter edges of the roof which can make finding the true source of the tile leak more challenging...the leak could be near the top of the roof, but be running down the foil making the leak appear many feet away.

When I first moved into my house I had few small leaks kinda like what you are having on two different occasions and locations on the roof. I called the builder, they came out, looked at where the leak appeared to be coming from, and said a couple of tiles didn't seem to be fully/properly set. Actually they had to tear the foil a in a few places to look at the roof from the underside also in order to find the true source of the leak. Each time if was some tiles that were not fully set into place/settled into the adjacent tile grooves/etc. After ensuring the tiles were firmly setting in the grooves and the overlapping tiles were laying flat, I had no more leaks. If the tiles are not set properly and when you have "wind blown" rain, the rain will just blow "under" the tiles/"around" the groves if the tiles are not fully settled down. That appeared to be my problem because the leaks went away...haven't had any leaks since and that has been years.

Later on, from looking at the roof from ground level I could also see some tiles that were chipped/had missing pieces on the bottom corners, normally where they overlapped the tile below them. I bought myself a ladder to get on he roof, adjust my C Band antenna, etc., and replaced these half dozen or so tiles "just in case" as I knew the chips/missing pieces allow less of an overlap which means wind-blown rain (sideways rain) might find its way in in a strong, side-ways type rain. I watch the wind and rain swirl around on my neighbor's roof across the street and that visual makes is so easy to understand how if a tile is not "fully settled down" that wind will just push rain underneath it or from the side.

The tiles are pretty easy to replace as their weight/interlocking is the only thing that secures them....properly lift up some of the surrounding tiles and the tile you want to replace will just slide out...then you slide in the new tile and let the tiles around it settle back down on the new tile. Now, you may have a few tiles along the valleys that have some wires through holes help to securing them but those are easy to replace also. Now the tile at the very top ridge of the roof are probably cemented in place so those are more challenging to replace. But generally, replacing roof a few pieces of roof tile is really easy, but be careful while on the roof.

And move around gently on the tiles as the weight of a heavy person/farang can crack them, which would cause a leak. I cracked a few in replacing the chipped tiles, buy hey, I bought exact replacement tiles at Home Mart for 13 baht each. I have about a half a dozen tiles in my storage room just in case I need to get on the roof again for something and my weight cracks a tile as I'm walking around the roof.

[richardjm65]

Yeah, we had this spray foam applied by the company you've mentioned. Our old tin roof was worn out, so we decided to replace it with tiles and since the roof pitch was shallow I was worried that in high winds rain might still be driven under the tiles. I have to say that I reckon the money spent on the spray foam job was the best I've spent on our house. In the fiercest rainstorms, I can barely hear the rain at all, there are no signs of any leaks, the roof tiles are effectively glued, so no likelihood of wind damage and any thief would have a tough job breaking through. The firm performed well under direction from its expat boss, covering up and masking areas that might be affected by overspray.

The acoustic insulation properties I've already mentioned, but the thermal insulation qualities provided another pleasant surprise. The temperature is far more even inside the house - on hot days it feels quite cool inside. We use the bedroom aircons less than before and there's been a reduction in our power bills, presumably a result of the improved insulation. I'd also heard some tales about temperature build up between ceilings and roof, but if this does occur, it is easily dealt with by installing louvred ventilation fittings at opposite ends of the roof space - any excess heat will be drawn out.

If I were to build another house, this sprayfoam job would be one of the essentials in my opinion - it's got my vote!

[wpcoe]

I've read that an additional benefit of the foam sprayed on to the underside of the tiles is to help burglar-proof the house. As mentioned above, it is easy to remove roof tiles to replace them. It is just as easy for a burglar to remove a tile to be able to drop into the house. The spray-on foam cements the tiles together. OTOH, if for some reason you need to replace roof tiles, the spray-on foam makes it more challenging to remove individual tiles.

[Pib]

To the OP, where you say: "Everything was bone dry, which amazed me since I could still hear it and the water spots again formed on the ceiling."

If you are just looking around the ceiling from the access hatch to the roof area, I expect you are not able to see the entire ceiling/roof. I sure know I can't from looking at the ceiling with my body poked about half way through the hatch and using a flashlight to look around. With the structure/construction of the ceiling beams and second floor, I just can't see all ceiling areas. "If possible" you might want to see if you can somehow move around up in the ceiling area in order to see all areas, especially since you said you can hear the leak. Doing such a check during a bright and shining day may prove benefical also by looking for beams of light sneaking through the tiles.

Also keep in mind that if the rain is pretty much coming straight down with little wind, then you may not experience a leak. But with wind blown rain, which creates swirling patterns on the roof, the rain is much more capable of finding any little hole, tile not properly seated, etc. And of course you know, if you see the dripping of water that this drip point may not be the tile intrusion point, as water on a slanted roof will run along the underside of the tiles or along the support roof structure until gravity makes the water drip straight down.

Water leaks in roofs can be a real pain to find sometimes, especially when they don't occur during every rain. Good luck.

Edited May 1, 2011 by Pib

[curtklay]

Thanks Gents for the input!

While the jury is still out on the foam spray, I had a "roofing specialist" come out and inspect. His explanation is that the roof gullies are installed incorrectly. A photo is attached showing that the metal strip does not extend far enough under the tiles to keep water from seeping in (most obvious on the left side of the photo). Once the water gets in, it will run in various paths causing the drips onto the ceiling in various places. In addition, he says the tiles should have been brought further in over the gully forming an overhang, and exposing less of the gully.

It seems to make sense, and would explain why I hear the drops hitting the ceiling in different areas depending on the wind and how hard it's raining. The gully issue was also brought up in a previous post by "Rimmer" who said 90% of roof leaks are related to the gullies or where roof sections join. (Thanks to Rimmer for pointing that out).

So, I'm convinced enough to confront my builder about how he wants to handle the 5 year warranty he gave on the roof. I'm sure I'll be met with some resistance, but I'm not going to let it slide. The expert said in 2 years, the ceilings will be ruined and I believe it. Since my first post, it rained again and water did actually drip through the ceiling in one spot, so it is a worsening situation.

A photo of one gully is attached. Any further comments are appreciated.

[Beardog]

Thanks Gents for the input!

While the jury is still out on the foam spray, I had a "roofing specialist" come out and inspect. His explanation is that the roof gullies are installed incorrectly. A photo is attached showing that the metal strip does not extend far enough under the tiles to keep water from seeping in (most obvious on the left side of the photo). Once the water gets in, it will run in various paths causing the drips onto the ceiling in various places. In addition, he says the tiles should have been brought further in over the gully forming an overhang, and exposing less of the gully.

It seems to make sense, and would explain why I hear the drops hitting the ceiling in different areas depending on the wind and how hard it's raining. The gully issue was also brought up in a previous post by "Rimmer" who said 90% of roof leaks are related to the gullies or where roof sections join. (Thanks to Rimmer for pointing that out).

So, I'm convinced enough to confront my builder about how he wants to handle the 5 year warranty he gave on the roof. I'm sure I'll be met with some resistance, but I'm not going to let it slide. The expert said in 2 years, the ceilings will be ruined and I believe it. Since my first post, it rained again and water did actually drip through the ceiling in one spot, so it is a worsening situation.

A photo of one gully is attached. Any further comments are appreciated.

Another mind boggling concept is the fact that they punch holes through the valley trough to hold the trough in place. Guaranteed leak within time. And C pac trains all their staff to install them this way.

[Pib]

The valleys could very well be the problem. Heck, even as a kid I remember my Dad always smearing some more tar in the valleys because of leaks. Seemed most leaks on our metal tile roof always occurred in the valleys.

The side metal strips of my valleys (I live in Bangkok) extend approx 8-12 inches "under the tile" on each side. Also, the trough of my valleys are real close to being as wide as yours, however, I only have approx 2-3 inch gap between the tiles for the water to drop down into the valleys. Yours look like there is a 6 to 8 inch gap between the tiles. A person shouldn't need concrete/patch material on the side of the valleys/tiles like yours appear to have....this is probably done for appearance and to help keep water out since the gap between the tiles is so wide.

[curtklay]

The valleys could very well be the problem. Heck, even as a kid I remember my Dad always smearing some more tar in the valleys because of leaks. Seemed most leaks on our metal tile roof always occurred in the valleys.

The side metal strips of my valleys (I live in Bangkok) extend approx 8-12 inches "under the tile" on each side. Also, the trough of my valleys are real close to being as wide as yours, however, I only have approx 2-3 inch gap between the tiles for the water to drop down into the valleys. Yours look like there is a 6 to 8 inch gap between the tiles. A person shouldn't need concrete/patch material on the side of the valleys/tiles like yours appear to have....this is probably done for appearance and to help keep water out since the gap between the tiles is so wide.

Thanks Pib.

I think we're on the way to solving this. I met with the builder, and he admits he made the valleys extra wide because he thought it would drain more water that way. Well intentioned, but unfortunately incorrect. We are negotiating on the cost to fix it. He really is a good builder, and did a beautiful job of building my house from just pictures and international phone calls, so I can't be too hard on him. Hopefully we will get this resolved.

[Pib]

The valleys could very well be the problem. Heck, even as a kid I remember my Dad always smearing some more tar in the valleys because of leaks. Seemed most leaks on our metal tile roof always occurred in the valleys.

The side metal strips of my valleys (I live in Bangkok) extend approx 8-12 inches "under the tile" on each side. Also, the trough of my valleys are real close to being as wide as yours, however, I only have approx 2-3 inch gap between the tiles for the water to drop down into the valleys. Yours look like there is a 6 to 8 inch gap between the tiles. A person shouldn't need concrete/patch material on the side of the valleys/tiles like yours appear to have....this is probably done for appearance and to help keep water out since the gap between the tiles is so wide.

Thanks Pib.

I think we're on the way to solving this. I met with the builder, and he admits he made the valleys extra wide because he thought it would drain more water that way. Well intentioned, but unfortunately incorrect. We are negotiating on the cost to fix it. He really is a good builder, and did a beautiful job of building my house from just pictures and international phone calls, so I can't be too hard on him. Hopefully we will get this resolved.

Here's a couple pictures of my home's valleys....and I looked around at my neighbors' houses on my soi and the next soi over, and they are all the same way....only a small gap. I never hear anyone complaining about leaks. Actually there appears to be only a 1 to 2" gap between the tiles. Or said another way, there is about a two finger width gap.

Edited May 4, 2011 by Pib

[curtklay]

The valleys could very well be the problem. Heck, even as a kid I remember my Dad always smearing some more tar in the valleys because of leaks. Seemed most leaks on our metal tile roof always occurred in the valleys.

The side metal strips of my valleys (I live in Bangkok) extend approx 8-12 inches "under the tile" on each side. Also, the trough of my valleys are real close to being as wide as yours, however, I only have approx 2-3 inch gap between the tiles for the water to drop down into the valleys. Yours look like there is a 6 to 8 inch gap between the tiles. A person shouldn't need concrete/patch material on the side of the valleys/tiles like yours appear to have....this is probably done for appearance and to help keep water out since the gap between the tiles is so wide.

Thanks Pib.

I think we're on the way to solving this. I met with the builder, and he admits he made the valleys extra wide because he thought it would drain more water that way. Well intentioned, but unfortunately incorrect. We are negotiating on the cost to fix it. He really is a good builder, and did a beautiful job of building my house from just pictures and international phone calls, so I can't be too hard on him. Hopefully we will get this resolved.

Here's a couple pictures of my home's valleys....and I looked around at my neighbors' houses on my soi and the next soi over, and they are all the same way....only a small gap. I never hear anyone complaining about leaks. Actually there appears to be only a 1 to 2" gap between the tiles. Or said another way, there is about a two finger width gap.

Thanks again!

You've helped me pinpoint the problem. Your valleys are obviously done the correct way, and are a world apart from mine.

[Fookhaht]

At least you guys have builders to come and back up their work!

As a renter, I regularly complain to management about literally liters of water which pour into my office and bedroom during each rain. Manager/owner's response: "Live with it. ALL Thai houses leak." Indeed six families all around me (living in duplexes built by the same builder) all hang out their bedding and floor mats to dry after each rain inundates their homes. Small comfort.

[curtklay]

At least you guys have builders to come and back up their work!

As a renter, I regularly complain to management about literally liters of water which pour into my office and bedroom during each rain. Manager/owner's response: "Live with it. ALL Thai houses leak." Indeed six families all around me (living in duplexes built by the same builder) all hang out their bedding and floor mats to dry after each rain inundates their homes. Small comfort.

It is dumbfounding how crappy the building techniques are considering how much rain falls here. In the US, before they put on the tiles or shingles, there is plywood sheeting with felt, tar paper, or a membrane on top of that. Here you're lucky if they put a sheet of foil over the framework. (I don't even have that). Guess that's one benefit of permits and inspections being required.

Pib's roof looks exceptionally well done, and I'm using his pictures to show my builder how to correct the valleys.

Thanks again, Pib!

[merijn]

When i build my house they sprayed to whole roof from the inside with a special sort of expanding foam.

It is delivered in two separate barrels and mixed via a spray gun when they apply it.

They cover the whole roof including the hangers, boarding etc etc.

The foam expand to about 10 cm and it came with a 10 year guarantee against any roof leakage and no danger any more of roof tiles blowing of in high winds as the foam acts as a glue to the roof tiles and seals everything in.

This stuff works great and is easily done even when the house is already finished as they only an access hatch to the roof.

The temperature dropped about 10 oC under the roof after the foam was installed.

Not cheap but perfect stuff.

[curtklay]

When i build my house they sprayed to whole roof from the inside with a special sort of expanding foam.

It is delivered in two separate barrels and mixed via a spray gun when they apply it.

They cover the whole roof including the hangers, boarding etc etc.

The foam expand to about 10 cm and it came with a 10 year guarantee against any roof leakage and no danger any more of roof tiles blowing of in high winds as the foam acts as a glue to the roof tiles and seals everything in.

This stuff works great and is easily done even when the house is already finished as they only an access hatch to the roof.

The temperature dropped about 10 oC under the roof after the foam was installed.

Not cheap but perfect stuff.

Thanks for the input.

So far, the score is 2-0 in favor of the spray foam.