One of the things I really got out of the cool thai house prototype is that the bathroom really has to be well laid out prior to starting construction.  The plan (or house blueprint) will include some of the bathroom layout, but it is meant to be an overall guide and not exact.  You can't really lay out the bathroom until you decide on all of the things which will go in there and have measurements for everything, including toilets, bathtubs, shower enclosures, and sinks.  This same thing applies to everywhere in the house where cabinets and fixtures are going to be installed, but is especially true in the bathroom.

The first thing to decide is: Will each shower will have an individual hot water heater, will there be a central water heater.  A central water heating unit isn't all that much more expensive than a good individual shower unit, but there are a lot of added expenses in plumbing it in and in additional hardware.  The plumbing for the hot water should be copper, although there is also the option of using heavy metal pipe.  The problem is this: it will probably rust out after about 10 years and as it is encased in cement, this isn't a very good option.  You could design it so the copper plumbing runs above ground, but this isn't the way it is normally done.  It seems that there are a lot of people that deal with hot water plumbing who are really expensive, to the point of being in the rip-off category.  One copper plumber came to bid on doing the bathroom and related plumbing for the cool thai house and he wanted 10 times what the job eventually went for.  Another thing which drives up costs is that hot and cold faucets are much more expensive than normal cold water ones.  The bottom line here is that central hot water is nice but needs to be budgeted accordingly.

Since the bathroom and plumbing is one of the more expensive parts of the house, professional developers often try to cut corners.  What comes to mind are plastic bathtubs with poor quality drain kits and no 'p-trap'.  Plumbing in a bathtub is a lot of work and it isn't an easy thing to get at the under the bathtub plumbing once the tub is enclosed.  To save say 5000 Baht by using poor a poor quality bathtub and accessories isn't worth it.  A better option than a plastic bathtub is either a good acrylic bathtub or no bathtub at all.

Septics are another area to keep an eye on.  It is so cost effective to add a couple of drainage rings at the onset of building that it is almost always better to be safe than sorry.  The normal depth is 4 drainage rings, 5 or more is probably better.  Septics are normally pretty trouble free, but I've had past experiences of the water not seeping into the soil because of hardness of the soil.  There are companies that will bring a truck and pump out your septic for you, but this should only be required rarely.

Shower enclosures are gaining in popularity, and there are a lot of models on display at Homepro.  They range in price from about 8000 Baht all the way up to 100,000 or more.  A good quality one of tempered glass can be purchased for about 10000 Baht.  I can't see any advantage to buying the acrylic drain panel, which is an option, as a concrete and tile base seems to be very sturdy and works great.  If you purchase one an Homepro you can contract with them there for the labor, which is a good idea if you plumber hasn't done one before.  This may well be the case (your plumber not having ever installed a shower stall before), since these only started becoming popular recently.

Lastly, sink enclosures.  You can purchase sinks that come with a base, or a sink that is to be mounted in a enclosure.  The enclosure idea seems to be a good one as it looks pretty good, is durable and cheap.  Materials include cement, red bricks, tile, a door made or waterproof material and of course the sink itself.  The most expensive part of doing it this way will be the door itself, which will cost upwards of 1000 Baht.

Bathrooms will normally have windows set up at a height of 2.5 meters, like shown here.  (28-Mar-04)	To allow extra light into the bathroom I like the idea of supplementing with glass blocks.  They are inexpensive and when finished look really nice.  (09-Apr-04)
A septic here is nothing but a hole in the ground with some cement rings inserted.  The normal number of rings is 4, I would recommend using at least 5.  The cement rings come in 1, 1.2 and 1.5 meter diameters, the one show here are the 1.2 meter size.  (08-Apr-04)	This shot shows the correct way of laying down a foundation base for bathroom, in that the floor of the bathroom typically is 10 centimeters lower than the rest of the house.  Notice how the foundation base in this shot is lower for the bathroom than the main house.  (12-May-04)
The frame for a PVC bathroom doors are themselves made of PVC, and as such they need a support housing when they are being set-up, otherwise the weight of cement above the door will cause the frame to bend.  (15-May-04)	This shows the simplicity of the plumbing.  Each bathroom is serviced by two septics, one for solid waste and one for water runoff.  Normally there will be three runoff pipe per bathroom as follows; shower, sink and a runoff for the floor drain.  The pipes are run into the septic and then cemented in place.  (01-Jun-04)
For hot water plumbing this is the recommended way of doing it: copper pipe shielded with PVC tubing.  It isn't that easy to find copper pipe or copper workman here.  (02-Jun-04)	Sink plumbing.  This sink is fed by 1/2 inch hot and cold pipes coming in and there is a drainage exhaust going out.  The pvc pipes will later be cemented into the wall.
This shows hot and cold PVC pipes which are to be poured in cement on the back of the house.  (07-Jun-04)	This shot shows a cement pour in progress which will encase the hot and cold water plumbing in cement.  Also, the septics will be covered in concrete with a 4" PVC pipe for venting.
The plumber is here making a base for the shower enclosures.  You can also buy a acrylic base but it isn't necessary.  A cement tiled base like this works great.  (19-Jun-04)	This is an example of a 75 liter wall mount water heater.  There are many different sizes and brands of central water heaters, one like this costs about 10,000 Baht.  However these haven't really caught on yet (the normal type used is the individual shower water heater) so you will need to hunt to find someone to install it and do the hot water plumbing correctly.  Also, using a central hot water heater like this raises costs more than you would think, from copper pipe to hot/cold faucets, the cost really isn't in the unit itself but all of the associated plumbing.  This is a good decision to make before you start building the house, ie. central hot water or individual hot water heaters?  (21-Jun-04)
An example of a hand done bathroom cabinet.  These can be done inexpensively and a real sturdy.  The cabinet is made of red brick with a door made of waterproof material.	This is the start of a support or a bathtub. The tub will be supported by 4 rows of red brick.
A bathroom sink enclosure being tiled. (22-Jun-04)	If you go with hot water throughout the cost of the faucets increases by about 3 fold.  A faucet like this is around 2000 Baht.  (23-Jun-04)
The lower part of this picture shows the free drainage hardware that came with the acrylic bathtub.  The top is a heavy duty copper set with costs about 1500 Baht.  Using the low quality free drain kit wouldn't be worth it since it is a lot of trouble to later fix a plumbed in bathtub.	Each bathroom will have a floor drain something like the one shown here.  The plumber should slightly angle the floor so water runoff will flow to the drain.
A plumbed in shower enclosure.  These are just starting to become popular.  Acrylic ones can be purchased for around 8000 Baht, but one with safety glass will cost more than 10,000.	Bathroom doors are normally made of a waterproof plastic material like this one.
A critical piece of hardware which should be installed under the bathtub.  It prevents foul odors from entering through the drainpipe.  A plumber may or may not suggest using one, therefore you might want to buy one and request that he install it.  (24-Jun-04)	A view of a finished hand made sink enclosure.
A bathtub in the process of being framed.  It will be supported by 4 rows of red brick.  (25-Jun-04)	A terrible way to do septics.  Here one hole is being dug which will house a series of septics.  (02-Jul-04)
The problem with doing septics this way is that the materials will cross flow between septics.  Also the dirt pack will be tighter if each hole is dug individually.	With all of the work installing and plumbing in a bathtub, it would be a shame to start with a low quality plastic tub.  A good bathtub can be had for about 7000 Baht, where a plastic one costs just over 2000 Baht.  (06-Jul-04)
Preparation for a septic cover.  (08-Jul-04)	One example of a nice looking septic cover.  Some varieties are vented, with this type the septic must be separately vented.  (09-Jul-04)
This shows the septic being vented out the to the rear away from the house.  If it is the solid septic, PVC is sometimes used (as shown here) to direct the exhaust air out and away from the house.  (21-Aug-04)	For a sink comparison, here is a pedistal model that comes with the base included.  (28-Mar-04)

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