Advice getting started on a family house

[Netease]

One of the first things you will want to understand is the sun angle throughout the year, which is critical when positioning and designing the house, and the landscaping.

Here's the summer solstice: http://suncalc.net/#/13.7954,100.5029,8/2015.06.21/12:00

And the winter solstice: http://suncalc.net/#/13.7954,100.5029,8/2015.12.22/12:00

If you play around with the dates, you will see that from March to September (the equinoxes) the sun is mostly overhead, or a little to the North - meaning that the biggest issues are the East (sunrise) and West (sunset) sides of the house. From September to March, the sun comes from a very pronounced Southerly direction, and by the December solstice it really does have some angle to it - so much so that things like roof overhangs become completely ineffective against the afternoon sun.

Thank you for the links, I am planning my building at the moment on a couple of Rai out from Chiang Mai to the east which will be a long house to take in the mountain views. The SunCalc allows me to actually pin point my land and see the sunrise and sunset through the whole year by hours of each day. Thank you this is a 5 star link

[kitjohnson]

Two Storey Cons:

* More direct sunlight hits the ground floor walls and windows, because the roof overhangs are so high up - can be mitigated with 'skirt' roof sections.

* Heat rises - which means the second floor is generally hotter than what a single storey house would be - that can be mitigated as well though. We have now built a few houses where the staircase ends adjacent to an upstairs terrace area - so the hot air just flows right out of a screen door. In those houses, the staircase is usually the coolest room in the whole house, and the other rooms upstairs or no hotter than what a single storey house would be.

* Construction costs per sqm are about 10-20% more than single storey.

We've switched fromm one storey to two. I was keen to raise the whole house a whole storey, traditional Thai house-on-stilts style, with an open ground floor. However we thought for the cost of doing that, and of putting in a nice floor, why not put in some walls and - hey, we have a two-storey house. Is that over-simplifying things?

With two storeys comes staircases. I remember IMHO said something interesting about that - quoted above.

With almost all of the two-storey house plans we have looked at, the stair case is a U-shape (bending back on itself) and ending slap bang in the middle of the second storey. This seems problematic since heat will rise and it will get trapped there. There is an example of this over on a site for free government (Public Works Department) house plans. Plan 55.

Incidentally, that site was a bit of a gold mine for me. I was aware of the a bunch of free government plans, helpfully linked to from this post on the Teak Door Forum. However the plan I linked to above appears to be part of an new set of plans, many of which look more modern.

Back to the staircase issue. I've read a bit about whole house fans. If you put a whole house fan in the ceiling above the landing on the second floor, right at the top of the staircase and in the middle of the house, my guess is that you could get a good current of air through the house and into the attic. With a well ventilated attic, the problem might be solved.

The other solution is to go for something like IMHO mentioned. There are some examples here:

• Plan 53. The staircase is one one extremity of the house and so heat buildup wouldn't affect other rooms so much (I guess).
• Plan 50. The staircase ends by an exterior wall on the second floor. Open up a door or window and hey presto, somewhere for the hot air to go.
• Plan 56. A staircase with no bends, also ending by an exterior wall on the second floor.

I'm interested in creating something like a chimney effect, where the staircase draws warm air from the ground floor and exhausts out of a second storey window, door, or screen.

If anyone has any thoughts on this then please do post. We're getting closer to knowing exactly what we want from our layout, but issues like this are key to creating a house that is cooled efficiently.

[IMHO]

Plans 53 & 56 have little to no roof overhangs = hot. Plans 50 & 55 are soul-less, style-less boxes. Keep searching - you can do a lot better than this. Try an SE-ED bookstore.

[kitjohnson]

Plans 53 & 56 have little to no roof overhangs = hot. Plans 50 & 55 are soul-less, style-less boxes. Keep searching - you can do a lot better than this. Try an SE-ED bookstore.

I just chose those plans to think about the staircase design and placement. I wasn't considering them for us at this stage. We're going to have a better look at them this weekend, and maybe get off to a bookshop too :-)

[fang37]

Get a better builder - not the cheapest. Medium size operator preferable to a big operator. Look at some of his recent jobs. Has he done many farang quality work?

Drainage - important

Insulation - similar

Mats - the best you can afford

Architect, books etc - No unless you are spending B8-10+m. Look at project homes & modify the plan.

Watch carefully that the mats purchased are in accordance with the agreement.

One level v 2 level - personal preference.

Ensure that your personal relationship is rock solid. -

Ensure that your missus has both feet on the ground.

Contact an astrologer - you need a lot of luck! Get 2 astrologists.

Whatever your budget is, add 20-50% extra.

Time - add 1/3 & be careful re rainy season.

Assess the optimum direction the house is facing.

Don't employ relations/friends of family

Other then the above, it is very easy.

[kitjohnson]

Get a better builder - not the cheapest. Medium size operator preferable to a big operator. Look at some of his recent jobs. Has he done many farang quality work?

Drainage - important

Insulation - similar

Mats - the best you can afford

Architect, books etc - No unless you are spending B8-10+m. Look at project homes & modify the plan.

Watch carefully that the mats purchased are in accordance with the agreement.

One level v 2 level - personal preference.

Ensure that your personal relationship is rock solid. -

Ensure that your missus has both feet on the ground.

Contact an astrologer - you need a lot of luck! Get 2 astrologists.

Whatever your budget is, add 20-50% extra.

Time - add 1/3 & be careful re rainy season.

Assess the optimum direction the house is facing.

Don't employ relations/friends of family

Other then the above, it is very easy.

Thanks a lot for the advice!

We've decided against using an architect because for a quality one we would need to pay a lot. Our budget is under 3 million. But our next thought was books - choose a plan and modify it to suit us. You said to go for 'project homes' - what's that?

[fang37]

"Project home" is one constructed in their development. Most designs are similar & cost saving is paramount.

This was a suggestion so that you can determine what you might expect for your $$$.

Take the good ideas & modify.

I cannot over-emphasize insulation aspects including roof tiles.

There are some things you can defer. Prioritize!

[kitjohnson]

After a great deal of discussion and thought, we've come up with a preliminary plan. Here are the plans and elevations. I drew this in Sketchup, and as you'll see, I'm a real beginner. I deliberately didn't draw wall thickness as it makes it much easier to change at this stage. When things are more firmed-up I'll redraw it with real thick walls.

The plan is based on a design we found in a book, though with quite a lot of customisation. Some basic details - like how high we'll raise it from the ground, window placement, wall materials and thickness, ceiling height, roof design, etc. - we hope to sort out in discussion with an architect.

I'm attaching this plan in case anyone has any helpful comments about stuff we should consider changing before we approach an architect. I'm particularly thinking about orientation of the house on the land, but any comments are really welcome.

Here are some passive cooling features that we've tried to build in:

• minimise glass on the south and west sides, and shade these with trees
• we are considering cavity walls on the south, west, and east sides
• the staircase is on the south side of the house, and with a window at the top, the hot air from the ground floor will have a way to escape the house
• the ground floor kitchen, dining and sitting are one big room, and we hope to open up windows and doors to this area during the morning when the air is cooler. When the outside air gets hotter, we'll close up the windows and folding doors.
• if we want to run air-con in the sitting room, we'll close the folding doors that separate it from the dining area. This makes a much smaller space to keep cool.
• the master bedroom has a separate dressing area. Again, running air con during the night we are dealing with a smaller space (16 square metres) rather than cooling a combined bedroom/dressing area.
• my idea for the roof structure is to have two gable ends, with louvres, to allow hot air to escape from under the roof. I have no idea if the roof as I have drawn it is feasible.

I've got one specific question: In the main house the maximum distance between columns is 4 metres. However, ideally we would make the dining area a little bigger. Could we increase the span between columns (2) and (3) to 4.5 metres without adding significant difficulty/extra cost?

That's it. Thanks everyone so much for your help on this thread so far.

[kitjohnson]

Notes on plans:

• I notice the section plane for the first floor plan didn't cut low enough, and we can still see some roof where we shouldn't. The staircase does take the full 2 metres.

Notes on elevations and 3D:

• A couple of windows appear to be missing their transparent blue shading
• there are a bunch of artifacts from my inexperience with this program (e.g. horizontal lines that run around the house)
• I haven't drawn the front door. it's just a grey rectangle right now.

[Thorgal]

You will find more hits in Thailand and in general under : 'passive house' and 'passive cooling'.

House design should be in function with direct natural resources and forthcoming choice in construction materials.

In some cases you need heat in order to create green energy: solar, heat pump, sun boiler, etc :

Some references and tutorials :

http://www.builditsolar.com/Projects/Cooling/passive_cooling.htm#Passive

There's know how in Thailand for your project. But 3M is limited...due to the more expensive construction materials.

Till now I didn't see any post about required 'k' factor or thermal conductivity...which you need for your design of a passive house.

Edited February 8, 2016 by Thorgal

[khunPer]

»I've got one specific question: In the main house the maximum distance between columns is 4 metres. However, ideally we would make the dining area a little bigger. Could we increase the span between columns (2) and (3) to 4.5 metres without adding significant difficulty/extra cost?«

To my knowledge, you count 4 meter distance between columns as 40 x 20 cm beam, 6 meter as 60 x 30 cm; so 4½ m should then be a beam of 45-50 x 23-25 cm. Posts should increase similar, so 25 x 25 cm posts instead of 20 x 20.

Change in post and beam size will then both be for post 2 and 3, and the opposite posts by the stair.

Your dining table looks a bit oversize, like around 2.80 x 1.20. Seating 6 persons you could look for something in the range of 1.80 x 0.90 and place 2 chairs each side, and one chair each end.

A question to your drawing: Do you plan a narrow door into bedroom #2..?

From my experience I would give little more space for the stair, you have counted 2 meters in width, post-center to post-center. With walls and plaster and banister, you may end up with an 80 centimeter wide stair, which may be extremely difficult to carry stuff up to 2nd floor, for example a king size mattress. I would add some more space between the posts, say 2.20 or up to 2,40 meter, so your stair will be minimum 90 cm wide or preferably 1 meter, which also gives you that more space on 2nd floor to re-size bath 2 and the door into bedroom 2.

You may have to check the beam strength under bath 1, but you may not have sketched beams at all. Again, I would make bedroom 2 little wider than 3 meter between column centers, if you ever think of a king-size bed going in there (count something like 2.20 x 2.00 meter in planning to have enough space). However, if you re-size post separation on ground floor to 4.50 meter in dining area, that may give you an extra 50 centimeter to bedroom 2.
When I draw my house – and I did spent long time doing it with pencil and rubber on millimeter paper – I tried to visualize all rooms and corners, finding similar sizes to get impression, and made physical markers to get the feeling of enough space in for example bathrooms and kitchen; consider how each door opens and possibility of collisions, etc. etc. Lots of wipe out and re-drawing; just 10 to 20 centimer can do a huge difference to the feeling of comfortable room size.

Just some immediate thoughts, if that can help you – wish you good luck with the project.

[William C F Pierce]

After a great deal of discussion and thought, we've come up with a preliminary plan. Here are the plans and elevations. I drew this in Sketchup, and as you'll see, I'm a real beginner. I deliberately didn't draw wall thickness as it makes it much easier to change at this stage. When things are more firmed-up I'll redraw it with real thick walls.

The plan is based on a design we found in a book, though with quite a lot of customisation. Some basic details - like how high we'll raise it from the ground, window placement, wall materials and thickness, ceiling height, roof design, etc. - we hope to sort out in discussion with an architect.

I'm attaching this plan in case anyone has any helpful comments about stuff we should consider changing before we approach an architect. I'm particularly thinking about orientation of the house on the land, but any comments are really welcome.

Here are some passive cooling features that we've tried to build in:

• minimise glass on the south and west sides, and shade these with trees
• we are considering cavity walls on the south, west, and east sides
• the staircase is on the south side of the house, and with a window at the top, the hot air from the ground floor will have a way to escape the house
• the ground floor kitchen, dining and sitting are one big room, and we hope to open up windows and doors to this area during the morning when the air is cooler. When the outside air gets hotter, we'll close up the windows and folding doors.
• if we want to run air-con in the sitting room, we'll close the folding doors that separate it from the dining area. This makes a much smaller space to keep cool.
• the master bedroom has a separate dressing area. Again, running air con during the night we are dealing with a smaller space (16 square metres) rather than cooling a combined bedroom/dressing area.
• my idea for the roof structure is to have two gable ends, with louvres, to allow hot air to escape from under the roof. I have no idea if the roof as I have drawn it is feasible.

I've got one specific question: In the main house the maximum distance between columns is 4 metres. However, ideally we would make the dining area a little bigger. Could we increase the span between columns (2) and (3) to 4.5 metres without adding significant difficulty/extra cost?

That's it. Thanks everyone so much for your help on this thread so far.

Having read through all these posts one thing no-one mentions is the Thai lack of using lintels over doors and windows. Can be a problem that causes cracks in the wall of door and window corners. The other thing to consider is an adequate damp proof course to alleviate rising damp from the wet season. Unless the building is being raised above the ground level. The old traditional style of Thai

is tiered roof like the temples allows hot air to rise and flow out of the overlaps. That's why it is nice and cool inside the temples on a hot day. But costs will not allow you to add this type of roof. Adding a screen wall vent might be useful. Have you considered the cold weather like the end of January 2016. Would it be warm enough for that odd 1 week a year. The drawings neat, tidy and cohesive, they work well in an overall design. This thread has been very useful for ideas for when I start my own home project end of next year. Many thanks.

[kitjohnson]

I feel like this thread has gotten old now, so I will probably create new threads when I get a specific question. Like whether a 20 degree pitch for the roof is too shallow - just posted that question over on Cool Thai House.

I just wanted to say thanks to William Pierce and Khun Per for the helpful comments. The architect we've hired had very similar comments to you, Khun Per.