One of the most important decisions you make about the house you are going to build is the type of roofing material you use.  There are two major ways to go here, tile or synthetic roof sheets.

Heavy tile:  Nowadays this is the material of choice.  It is very pretty and durable.  Tile roofs add value to your house and put it in a different price category -- this becomes important should you decide to sell at some point in the future.  The downside for tile is it is extremely heavy, and this requires a large and sturdy metal substructure which is expensive.  Tile also cracks and chips easily if it is walked on.  This normally isn't an issue except for cases where roof access is required.  It is not secure in the sense that someone can easily gain illegal entry to your house by misplacing a few roof tiles.

Synthetic roof sheets:  If you know you are building a house to live in forever and are simply not worried about resale value -- this may be the way to go.  The roof sheets come in a variety of qualities, materials, and colors and will end up being a lot cheaper to install.  As far as I know there are no downsides, EXCEPT (and it is a big except!) it isn't as pretty and if you've built a high quality house with sheet roofing the resale market won't be there.

This is one of those rare instances where paying more money doesn't lead to an increase of quality.  If I were put on the spot and had to answer the question, 'Which roofing material is of better quality?', I would have to answer 'Synthetic roof sheeting'.  This being said, in the future I will continue to use heavy tile since it is functional and the marketplace demands it.

The heavy tile roofing is all pretty good quality and starts at about 8.2 Baht a piece.  One thing I did notice is that they gouge you when you buy the special pieces, ie. the corner pieces or top pieces (which can cost 4 or 5 times as much as a standard piece).  When choosing the store and tile you are going to purchase I advise getting a price on all of the pieces up front so you won't be surprised later.

Another option which is recommended and commonly used today, is roofing insulation.  This is especially appropriate if you plan to use air conditioning and have a low profile roof, as it will retain much of the cold air and lower your electricity bill.

Materials

Synthetic roof sheeting of which there are a myriad of colors and qualities.  Much cheaper overall than tile roofing.  (21-Apr-04)	More sheet roofing examples.  These pieces are about 60 centimeters long.
A house with a roof made of synthetic roof sheeting material.  (12-May-04)	Close up of synthetic roof sheeting material on the roof.
Another example of a house in progress with a synthetic roof.  (20-Jul-04)	This close up of the same house shows the truss structure.  The truss is made of mostly of wood.
Closer view of the raw tiles.  These tiles are being lifted up to the roof via a rope.  Remember each tile weighs about 4 kilograms.  (28-Mar-04)	Tile roof example (cool thai house).  This is the most common roofing material in use for houses built for foreigners.  (03-May-04)
Tile roof example.  (13-Aug-04)

These are some shots from the cool thai house roof.  Three specific things I would suggest when doing a roof: 1). Subcontract the roof out to a company that does only roofs.  2.) Make sure that the aluminum sheeting used in the valley is of proper width, at least a meter wide.  The standard aluminum drainage sheeting sold for use in valleys is not sufficient.  3.)  Make sure that the supporting walls are completed prior to laying the tile on the roof.  Otherwise the roof metal will bend.

The roof structure is built using heavy gauge steel. The bigger pieces are 4 * 2 inches and 3.2 mm thick. The smaller pieces are 1 by 1inch and 1.6 mm thick. There are two designations, full and light, this is the full heavier gauge variety. (13-Mar-04)	The roof tile will lie on the 1 by 1, so they must be placed at proper intervals. Notice the cross beam supports which sits on top of the foundation posts.
This shows most of the foundation columns as well as the partially finished roof truss. The roof height is 2.75 meters about the foundation pillars, the foundation pillars are 3.50 meters to the overall height is 6.25 meters.	Partially finished roof truss, rear side of house.
This shot also shows the facia board (brand facolia, a synthetic material) along with an aluminum preformed strip for rain water.  This drainage strip is inadequate in size and leads to problems later.  It has a width of about 20 centimeters. (22-Mar-04)	For comparisons sake a pair of photos of another house which shows a wide strip of aluminum flashing (about 1 meter wide) being used which is a better way to do the roof flashing.  (15-May-04/09-May-04)
The roof tile is wired on to hold it in place. Notice the tile sits in place on the 1 * 1 metal cross beam.  (22-Mar-04)	A piece of wood is extended from the roof metal to allow the facia board to be attached.
The nearly complete roof truss.  The supporting walls must be complete prior to starting to lay tiles on the truss, otherwise the truss metal will bend.	Cement work on the roof tiles. (26-Apr-04)
Front valley being completed. (30-Apr-04)	Plastic inserts like these come in easy to install strips, each piece covering 3 sections (like the one shown).  The are used to prevent birds and rodents from entering the attic area.  (09-May-04)
Finished roof, view from left front.  (13-Aug-04)

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