Building a Roof in Thailand

[dirtydog]

Another in the series of dirtydogs DIY building projects, although here in Thailand you probably wouldn't want to spend all day up on the roof welding bits of steel together, yep it is hot here in Thailand.

Okay for a start I believe all roof trusses are made from steel now, I really don't think anybody in Thailand uses wood anymore as it is too damn expensive.

Now a nice roof has lots of differant areas to it and basically is all over the place looking nice, this will probably have to be worked on every year or two to repair leaks, cement and galvanised sheeting are not really that good for sealing or sorting out roofs, the cement cracks after a year or two and the galvanised sheeting is generally not big enough to cope with heavy rain storms, obviously the best roof style you can have from a maintenance point of view is an A frame roof, but hell they are ugly and they do work and if everybody had one it would put pikeys out of business.

So the first step is to order a load of steel and paint it in red oxide, the steel comes in 6 meter long pieces and is covered in some crappy oil stuff, wipe this down with thinners or whatever and then give it a coat or two of the old red oxide, normally here one coat is the norm, so if you ask for a second coat at this stage expect to pay more money for that, we do 2 coats while it is uncut as it is a lot easier painting the steel on the ground rather than in the roof, once it is in the roof generally the steel only gets touched up on the weld burns, but then again the slag aint even knocked off, yep problems for the future, but how long did you expect your roof to last?

[dirtydog]

So as above we shall stick to the really heavy "Monier" type of tiles, for these we need some real big steel supports as they are bloddy heavy, it really don't look so good when the roof sags, now the cross members we need about a 28cm spacing between each one so the tiles overlap real good, obviously this can be spaced out more and save money on steel but hell you got to live there, now for this we can use "L" shaped steel which is real cheap, or square steel which is damn expensive, yep depends on the job the big steel supports are set apart by 60 to 80 cms apart.

[man with no head]

Stupid question but how does the frame of the roof actually attach to the house? To the rebar left over in the supports, or, long bolts, etc.

[Bung]

They weld it to the rebar sticking out of the top of the vertical cement beams.

I have that corrugated fibro syle roofing with all the bolts sticking through but was just looking at a mates place and they have a new style of bracket to attach them now which looks much cleaner and they don't have to punch holes through it.

If you are building a roof like this demand these types of fixtures!

[man with no head]

How much more expensive is wood compared to the one shown?

[dirtydog]

I have no idea, don't know of anybody who has used wood to build a roof in years.

[man with no head]

This is sort of the roof design I had in mind (this is a mockup of a house design that I came up with).

[jumbo]

DD,
I have noticed that a lot of builders weld the steel to the rebar at the top of the uprights, as you show in the first picture, it looks strange to have these uprights held together with the steel of the roof. I have specified that beams be formed to tie in the uprights at the top of the walls. Do you think I am being a little over the top by requesting this.

Jumbo

[jumbo]

The new Bungalow in the picture, is it on the Egmongkol (spelling) on Teprasit.
Jumbo

[dirtydog]

I have specified that beams be formed to tie in the uprights at the top of the walls. Do you think I am being a little over the top by requesting this.

Nope that is quite normal.

The new Bungalow in the picture, is it on the Egmongkol (spelling) on Teprasit.

It's actually the new Ekmongal village off of Soi Chayapruk 2.

[jumbo]

DD,

I know this is not going to be easy, but is there a ball park figure for roofing, steel work and tiles. I was thinking of tiles of the type in the photo of the Ekmongol bungalow.

Jumbo

[dirtydog]

2,500baht per square meter.

[Dougal]

Dog,

Do you base your estimate on the surface area of the roof or the roof's footprint? I hope that makes sense.

[dirtydog]

Generally the roof as no one wants a low sloped a frame type roof

[dirtydog]

A common problem is when building an extension, now your main roof is already up and a lot of the times you can't follow that line as it would make the ceilings to low, so you normally tie in under the exsisting roof and have a lesser slope on your exstention, now here in Thailand they would just chuck a load of cement in the join to stop leaks, trouble is 90 percent of the time this doesn't work, and even if it does you will get leaks within a year or two, so then every year you got to get a guy in to weather coat it with the water proof black stuff and get him to repair any damaged ceilings, this is pretty much gauranteed to be a yearly thing, don't sound much fun does it that'l teach ya to go for the cheapest

Ok this way does work out more expensive in the short term but it is the only proper way to do it, get a couple of idiots up on that roof and get erm to chip out all that old concrete, don't start whinging if they damage some tiles as sometimes concrete does stick real good to roof tiles, not very often though which is what causes the leaks, go out and buy a load of galvanised sheeting, this comes in 8 by 4 foot lengths, get the guys to take off the first two rows of roof tiles and tie your galvanised sheeting to the rebar, yeah it looks ugly but it is a damn sight better than being flooded everytime it rains.

[dirtydog]

Just thought I should add these roof tiles to the thread, this is probably the cheapest way to build a roof, the tiles are very light and big and cheap, so you don't need too much steel to hold them up, also they come in lovely assorted colors.

[Marmite the Dog]

^What are they made from? Do they last well?

[Dougal]

These houses are being built very close to me. Instead of Monier tiles they are using some sort of tar tile impregnated with coloured grit. I don't know the cost or where you would buy them. They are being laid on chipboard attached to a light weight steel frame.

I guess that they are a lot lighter and thus cheaper than conventional concrete roofing tiles, although as these houses start at 20M Baht you wouldn't expect cost to be a big problem.

I have no idea what the durability of this type of construction is; mybe DD knows.

[El Gibbon]

Look very similar to roofing tiles used in the NE U.S. The new stuff is guaranteed for 20+ years in a tough climate. Ice and snow buildup are the primary causes of failure.

Rain in the tropics shouldn't be a problem but don't know how they would stand up to the heat.

Easy to install, (staple gun) light weight and seal really well on the first warm day.

E. G.

[DrAndy]

I have no idea, don't know of anybody who has used wood to build a roof in years.

now you do, me, I done it guv

[The_Dude]

These houses are being built very close to me. Instead of Monier tiles they are using some sort of tar tile impregnated with coloured grit. I don't know the cost or where you would buy them. They are being laid on chipboard attached to a light weight steel frame.

I guess that they are a lot lighter and thus cheaper than conventional concrete roofing tiles, although as these houses start at 20M Baht you wouldn't expect cost to be a big problem.

I have no idea what the durability of this type of construction is; mybe DD knows.

D,
This is very similar to roofs being built on the West Coast in the States. OSB what you call chipboard is also used on walls and sub-flooring due to it's strength and cost ratio. It is very popular with building contractors. The down side is, if exposed to alot of moisture it will deteriorate and loose it's strength also this stuff when caught on fire is Hell on Earth! And as for the roofing material it looks like asphalt shingles which has a different warranty life depending on grade quality. And also climate where the material will be used. This stuff also when caught on fire will be hard to put out. Interesting to see new products available in LOS. I wonder if these products will hold up to what thailand has to offer, ie., Humidity, Insects, etc.

[Panda]

We own an old timber place. But we plan to tear it down and build a new house on the block. I was hoping to use galvanized metal sheeting for the roof, but I haven't seen much of it around except for the older places.
All the new places seem to be tiles. I would have thought metal sheeting would be cheaper and less roof structure required.

[Dougal]

Instead of metal the roof sheets here are made of some sort of concrete fibre. Pretty light compared to tiles and should last just as well. If the house is for yourself and you are not intending to sell it any time soon that material will be fine. But C-pac Monier or similar undoubtedly look better.

[Panda]

Instead of metal the roof sheets here are made of some sort of concrete fibre. Pretty light compared to tiles and should last just as well. If the house is for yourself and you are not intending to sell it any time soon that material will be fine. But C-pac Monier or similar undoubtedly look better.

My main concern is that we need to span 10 meters on the upstairs patio and is going to take some substantial roof trusses. The lighter the roofing material of course the lighter the trusses will need to be.

[qwerty]

A lot of cheaper Thai buildings use a kind of lightweight corrugated fiberglas/asbestos sheeting that seems to hold up well. DD or others might be able to give you the plusses and minuses of using it!