Roofing (clay Roof Tiles)

[Nirvana]

Hello All

I am building an outhouse / bar with clay roof tiles with a natural colour (not orange) as I understand it they are around 11- 15 baht a piece. Roof size is 80 sq meters or so.

They will be fixed onto a steel structure which will be checked by an engineer as this is going to be pretty heavy. See attd pictures

What I would like to know is normally just so i can check contractor is doing it correctly, is the procedure for fixing and underneath the tile.

Is it again best to use the foil etc. A brief idiots guide on process and check list would be well appreciated just so i can monitor personally.

Thanks

Nirvana

[Rimmer]

It looks like your contractor has used L section steel as roof battens, in which case I suspect the tiles will be wired on.

The correct galvanized 'top hat' section batten is only slightly more expensive and allows tiles to be screwed onto the rail.

Any foil should be under the rails not on top of it.

If you want to put foil on top of the rails you can but you will have to use a heavier grade of foil to prevent the tiles punching though the foil.

[stgrhe]

Any foil should be under the rails not on top of it.

And if the shining side is put upwards there should be an airgap of minimum 5 cm to the tiles, else the foil will not reflect the radiant heat properly and it will be a waste of money.

If you use foil, ensure you insert air gaps on the upper part of the walls so the thermal heat has an exit.

[Nirvana]

It looks like your contractor has used L section steel as roof battens, in which case I suspect the tiles will be wired on.

The correct galvanized 'top hat' section batten is only slightly more expensive and allows tiles to be screwed onto the rail.

Any foil should be under the rails not on top of it.

If you want to put foil on top of the rails you can but you will have to use a heavier grade of foil to prevent the tiles punching though the foil.

Hi Rimmer

any idea where I would source that "top hat section" and the name in thai (i knw i am pushing it)

Thanks

Nirvana

[Nirvana]

Any foil should be under the rails not on top of it.

And if the shining side is put upwards there should be an airgap of minimum 5 cm to the tiles, else the foil will not reflect the radiant heat properly and it will be a waste of money.

If you use foil, ensure you insert air gaps on the upper part of the walls so the thermal heat has an exit.

Hi Stgrhe

Ok , so Shiny side facing outwards towards back (inner side ) of tile. As is if the foil is fixed on inner side of frame then it definately will not be 5 cm between tiles. any ideas ?

Noted on air gaps.

By the way for an outhouse with bar under do you think it will make much difference not to use foil in first place , I .e is it necessary ?

Thanks Nirvana

[Rimmer]

It looks like your contractor has used L section steel as roof battens, in which case I suspect the tiles will be wired on.

The correct galvanized 'top hat' section batten is only slightly more expensive and allows tiles to be screwed onto the rail.

Any foil should be under the rails not on top of it.

If you want to put foil on top of the rails you can but you will have to use a heavier grade of foil to prevent the tiles punching though the foil.

Hi Rimmer

any idea where I would source that "top hat section" and the name in thai (i knw i am pushing it)

Thanks

Nirvana

It's available at all Home Mart style shops that sell roofing tiles as it's part of the system.

There are many different prices for rail. C Pack rail is probably the most expensive but the generic brands are OK as well.

They come in a six meter length. The rail is screwed to the C section steel using C Pack steel roofing screws which have a built in drill bit and go through the rail and steel like butter. Use the small high speed Maktec electric hand drills with a screwdriver bit in the chuck.

Edited October 1, 2009 by Rimmer

[Rimmer]

Here you can see the rail and how the foil goes underneath the rails. An air gap of 5cm is a new one on me but the rails are quite deep so maybe....

[stgrhe]

Here you can see the rail and how the foil goes underneath the rails. An air gap of 5cm is a new one on me but the rails are quite deep so maybe....

You can find several studies on the internet about the foil and how it should be applied in order to reflect the radiant heat. Radiant barriers must have an air space, hence the 5 cm, that faces at least one of its reflective surfaces in order to function properly. When the reflective surface is too close or in direct contact with another surface, it becomes a conductor of heat.

Also, when a radiant barrier in an attic is installed horizontally, dust accumulation over time will reduce the effectiveness of a radiant barrier.

[fremmel]

Ok , so Shiny side facing outwards towards back (inner side ) of tile. As is if the foil is fixed on inner side of frame then it definately will not be 5 cm between tiles. any ideas ?

It looks like there's some confusion on which way to put the shiny side. As Stgrhe says there must be an air gap next to the shiny side for it to be effective. So, if you decide to put the shiny side on the top then make sure it's under the battens.

But for most roofs it's much better to have the shiny side pointing down. That way you get a good air gap and you don't have the dust settling on the shiny side degrading its performance.

And I'd like to add an endorsement for using the foil. It will make a major difference in how comfortable outhouse/bar is on sunny days.

[slapout]

Wire tie roof, just watch when they install tiles as the workers seem to have a tendency to tie what and when they want to. If you have access to roof from below (access door) every tile can be tied. I have watched tiles going on where they tied every tile, every other tile, every other row of tile, every third row of tile, and once where no tile were tied.

[Beardog]

Shiny side pointing down!

If you are going to use battens as Rimmer suggested you can save a bunch if there is a Kangyong store around there battens & other supplies Clips are cheaper Foil about the same. & will handle the same load for the tiles. You can get Silka brand rolls for the flashing also instead of the small rolls you get a large roll for 1000 baht with 6 times the amount of material & just cut to fit. Home mart has most of the goods....I would use your own team or contractor to do the job. Unless you like bloated belly prices. They cut corners just like most of the workers. Home mart has independent companies within each homemart so if you can shop around different homemarts for the best price.

Good luck if all goes well I will be doing my roof around march.

Barry

[Rimmer]

Wire tie roof, just watch when they install tiles as the workers seem to have a tendency to tie what and when they want to. If you have access to roof from below (access door) every tile can be tied. I have watched tiles going on where they tied every tile, every other tile, every other row of tile, every third row of tile, and once where no tile were tied.

I think the OP is using the small clay tiles on a smallish roof which can of course all be wired on.

If however a normal C Pack style roof is fitted it is usual to fix every other tile otherwise tiles can not be removed, the roof can not be repaired, the void space can not be accessed and the tiler can not slide tiles up to use the batten rails as a ladder to reach ridge tiles. Also the UBC man hates you because he can not get his cable under the tiles.

[Nirvana]

Wire tie roof, just watch when they install tiles as the workers seem to have a tendency to tie what and when they want to. If you have access to roof from below (access door) every tile can be tied. I have watched tiles going on where they tied every tile, every other tile, every other row of tile, every third row of tile, and once where no tile were tied.

I think the OP is using the small clay tiles on a smallish roof which can of course all be wired on.

If however a normal C Pack style roof is fitted it is usual to fix every other tile otherwise tiles can not be removed, the roof can not be repaired, the void space can not be accessed and the tiler can not slide tiles up to use the batten rails as a ladder to reach ridge tiles. Also the UBC man hates you because he can not get his cable under the tiles.

All reply posters

Morning.

Thanks to every one for their time. I am going to look at this over next 2 days and decide. The tiles I am looking at buying are PPK orange clay tiles , 5 inches w by 9 inches L. They are around 9 baht a piece. roof size is 80 sq m . 1 sq meter is 75 pieces and each tile is 0.5 Kg roughly.

ONe thing notice from the sample is there is no holes at all in the tile so any pics on how they are tieing these on ?

Any further advise / comments deeply appreciated before I go ahead on this one.

Thanks

Nirvana

[David006]

Wire tie roof, just watch when they install tiles as the workers seem to have a tendency to tie what and when they want to. If you have access to roof from below (access door) every tile can be tied. I have watched tiles going on where they tied every tile, every other tile, every other row of tile, every third row of tile, and once where no tile were tied.

I think the OP is using the small clay tiles on a smallish roof which can of course all be wired on.

If however a normal C Pack style roof is fitted it is usual to fix every other tile otherwise tiles can not be removed, the roof can not be repaired, the void space can not be accessed and the tiler can not slide tiles up to use the batten rails as a ladder to reach ridge tiles. Also the UBC man hates you because he can not get his cable under the tiles.

All reply posters

Morning.

Thanks to every one for their time. I am going to look at this over next 2 days and decide. The tiles I am looking at buying are PPK orange clay tiles , 5 inches w by 9 inches L. They are around 9 baht a piece. roof size is 80 sq m . 1 sq meter is 75 pieces and each tile is 0.5 Kg roughly.

ONe thing notice from the sample is there is no holes at all in the tile so any pics on how they are tieing these on ?

Any further advise / comments deeply appreciated before I go ahead on this one.

Thanks

Nirvana

Do you mean ceramic tiles? they ( and concrete) usually have a wire hole someplace and they attach to roof thereby with gal wire every second row. Without this high winds may leave you with some damp patches on your ceiling? Maybe your tiles need clips or suchlike?

Re insulation..nobody has mentioned venting or wind vane'd whirligig vents..do they use these in Thailand?

Also there are heat reflective coloured roof paints availble...

Air gap?? In the US and Canada they have f/glass bats coated with foil in wall insulation and then vapour barrier taboot plus gypsum/siding seems there is no airgap to speak of in that case???

Also I have seen lots of non air con'd shops (ceiling less)etc in LOS with the foil reflective side inside? ..maybe it's double sided? or the installer double scotched? Seen lots of samples of sealed foam foil coated ( both sides) different thicknesses etc..may be good stuff. din't use anything in the end....maybe put good old fg bats up there on the ceiling one day...

Don't understand the logic/expense of insulation under roof line if you have a ceiling..maybe to keep the geckos cool in the attic?

david

[Goinghomesoon]

No hole for the wire? Do you have traditional-style tiles with the wedge underneath that hooks over the batten ('kabuang kroc')?

[bangkokumpalumpa]

one thing that is worth mentioning is welding

take a hammer and go up there and bash lots of welds to knock of the slag and look at the quality of the welds, it can be shocking at times how scary the welding can be.

now a good weld will be stronger than the steel, a bad weld will weaken both and leave a point for corrosion.

ok how important are the welds?? well at 0.5kg per tile and 75 tiles to the sq meter with 80 sq meters that makes for 3,000kg or three tons of tiles plus the weight of the steel. all resting above your head.

you can also add to that loading with monsoon and wind loads.

here is a pic of a good quality weld

here is a pic of a bad weld

i really cant stress enough how important it is for you to inspect those welds!!!

I was a welding instructor here in thailand for some time for a very very high profile construction company I trained there construction crews, and to put it simple the work was scary!!!! hence they paid me big money to train there crews to get them up to standard!

it is common that this area is not looked at so the least amount of effort is put into the quality, but it is the area that you need the best quality, a tile or two coming off is not major but the roof falling down is!!!

[Nirvana]

No hole for the wire? Do you have traditional-style tiles with the wedge underneath that hooks over the batten ('kabuang kroc')?

Hi Going homesoon

Sorry for delays in posting. I will post some pictures very soon, but yes what you say is correct "kabuang kroc'.

The guy that did the roof structure screwed it up and was outed, spacing between the metal c section was off compared to the recommended distance on the detail supplied ( I was given a glance of but unable to copy). Ie now the amount of tile showing is about 2.5 cms more than it should have been.

Now we are advised to fold tin inbetween tiles before tiling the roof to assist in water proofing. I did ask about the ties and was advised that weight will hold it down at 35-40 kgs per square meter which is about 60 tiles now instead of 75 more or less.

Not a happy story so far..

comments appreciated

Nirvana

[Nirvana]

one thing that is worth mentioning is welding

take a hammer and go up there and bash lots of welds to knock of the slag and look at the quality of the welds, it can be shocking at times how scary the welding can be.

now a good weld will be stronger than the steel, a bad weld will weaken both and leave a point for corrosion.

ok how important are the welds?? well at 0.5kg per tile and 75 tiles to the sq meter with 80 sq meters that makes for 3,000kg or three tons of tiles plus the weight of the steel. all resting above your head.

you can also add to that loading with monsoon and wind loads.

here is a pic of a good quality weld

here is a pic of a bad weld

i really cant stress enough how important it is for you to inspect those welds!!!

I was a welding instructor here in thailand for some time for a very very high profile construction company I trained there construction crews, and to put it simple the work was scary!!!! hence they paid me big money to train there crews to get them up to standard!

it is common that this area is not looked at so the least amount of effort is put into the quality, but it is the area that you need the best quality, a tile or two coming off is not major but the roof falling down is!!!

Hello

I am certainly checking that for this place and also in other house the other day while up inspection hatch I found one that is not as it should be. Working on rectifing that. Cheers for the heads up

Nirvana

[Beardog]

one thing that is worth mentioning is welding

take a hammer and go up there and bash lots of welds to knock of the slag and look at the quality of the welds, it can be shocking at times how scary the welding can be.

now a good weld will be stronger than the steel, a bad weld will weaken both and leave a point for corrosion.

ok how important are the welds?? well at 0.5kg per tile and 75 tiles to the sq meter with 80 sq meters that makes for 3,000kg or three tons of tiles plus the weight of the steel. all resting above your head.

you can also add to that loading with monsoon and wind loads.

here is a pic of a good quality weld

here is a pic of a bad weld

i really cant stress enough how important it is for you to inspect those welds!!!

I was a welding instructor here in thailand for some time for a very very high profile construction company I trained there construction crews, and to put it simple the work was scary!!!! hence they paid me big money to train there crews to get them up to standard!

it is common that this area is not looked at so the least amount of effort is put into the quality, but it is the area that you need the best quality, a tile or two coming off is not major but the roof falling down is!!!

That would be a common Thai weld called dog piling & you are correct after a while you will be structurally doomed. I hope these hosers don't ever decide to modify an auto or truck frame OMG!!!!

[Goinghomesoon]

No hole for the wire? Do you have traditional-style tiles with the wedge underneath that hooks over the batten ('kabuang kroc')?

Hi Going homesoon

Sorry for delays in posting. I will post some pictures very soon, but yes what you say is correct "kabuang kroc'.

The guy that did the roof structure screwed it up and was outed, spacing between the metal c section was off compared to the recommended distance on the detail supplied ( I was given a glance of but unable to copy). Ie now the amount of tile showing is about 2.5 cms more than it should have been.

Now we are advised to fold tin inbetween tiles before tiling the roof to assist in water proofing. I did ask about the ties and was advised that weight will hold it down at 35-40 kgs per square meter which is about 60 tiles now instead of 75 more or less.

Not a happy story so far..

comments appreciated

Nirvana

Ouch Nirvana that doesn't sound too good. We are using smaller tiles (115 per sq.m) ordered direct from producer in Dan Kwian, Korat at either 4.5 baht or 5.5 baht per tile (we are in "discussions" with the supplier over price but that's a whole 'nother story). For us there are no ties, the tiles just hook over the battens and the weight of the rows on top hold them down per the old traditional Thai houses.

To stop leakage our builder suggested running a strip of silicon underneath each tile as it is put in place to waterproof in-between the tile layers. Apparently the tiles are usually fine when first laid (if laid properly, which it sounds like yours aren't) but the problems arise if they get shifted through wind or when the ground or house starts to settle. Then you can get little pockets where the tiles lift/shift and start letting the water through. Our builder assures us the siicon is the way to go but the tile company says it's not necessary. I'm a bit worried it might affect the natural breathing of the roof (these tiles soak up a lot of water when wet and that's what helps cool the house). We've not decided which way to go at this stage but maybe silicon is something you could explore too.

[stgrhe]

Do you mean ceramic tiles? they ( and concrete) usually have a wire hole someplace and they attach to roof thereby with gal wire every second row. Without this high winds may leave you with some damp patches on your ceiling? Maybe your tiles need clips or suchlike?

Re insulation..nobody has mentioned venting or wind vane'd whirligig vents..do they use these in Thailand?

Also there are heat reflective coloured roof paints availble...

Air gap?? In the US and Canada they have f/glass bats coated with foil in wall insulation and then vapour barrier taboot plus gypsum/siding seems there is no airgap to speak of in that case???

Also I have seen lots of non air con'd shops (ceiling less)etc in LOS with the foil reflective side inside? ..maybe it's double sided? or the installer double scotched? Seen lots of samples of sealed foam foil coated ( both sides) different thicknesses etc..may be good stuff. din't use anything in the end....maybe put good old fg bats up there on the ceiling one day...

Don't understand the logic/expense of insulation under roof line if you have a ceiling..maybe to keep the geckos cool in the attic?

david

It is important to understand that there are two kinds of heat, radiant heat and convection heat. Radiant heat is the heat generated by the sun or e.g. infra-red lamps while e.g. an electric element is generating convection heat.

Here in Thailand with our tropical climate the main purpose for using aluminium sheet insulation is to block the radiant heat from entering our houses and to be effective it needs a small air gap between the sheet and the roof tiles. Having said that, if an air gap cannot be accommodated the sheet works equally well if the shiny side is faced downwards.

The heat we and our equipment generate in our houses is convection heat and it should be vented out. That is why one preferably should have a vented attic. If the ventilation holes are done properly the physics will do the job for you replacing the hot air by cooler air.

[Nirvana]

Hi

Installed and up finally in time for rains.

Time will tell

Cheers for help

Nirvana

[Rimmer]

Hi

Installed and up finally in time for rains.

Time will tell

Cheers for help

Nirvana

Looks very nice, well done

[Goinghomesoon]

Hey Nirvana, any leaks with those tiles yet? I'm sending you a PM with a sourcing question.

[Trex52]

Any foil should be under the rails not on top of it.

And if the shining side is put upwards there should be an airgap of minimum 5 cm to the tiles, else the foil will not reflect the radiant heat properly and it will be a waste of money.

If you use foil, ensure you insert air gaps on the upper part of the walls so the thermal heat has an exit.

Heat rises. It will mostly collect in the peak of the roof. They are using this textured cardboard like (corragated) ridge cap stateside, where there is a gap at the very top of the ridge from the final row of shingles so the heat can dissipate through it. I sure would like to find something like that here, as I am getting ready to put a tile roof on our house that is under construction now. Even with dutch gables (hip and gable roof combo) and louvered vents, I think I will use the whirlie type peak vents. And they too, need to be mounted on the very top of the ridge, not just on the roof up near the ridge. Heat dissipation is the key to having a cooler house. trex