Which Way Should Your House Face?

[JimShortz]

that is an incorrect assumption. as the "long" sides have to take a big heat load from in the mornings and late afternoons when the sun is for a long time "low" whereas the heat load from the south is less due to the sun standing "high" in tropical and subtropical countries.

I agree entirely with this. Where i live in Chiang Mai the South facing walls do not get heated up because when the sun is in the south it is high enough to not fall onto the walls, and when it sinks a little lower an outbuilding protects my south side. It's the western side of the house that gets hot in the afternoons - this is the side that needs shading most. Actually, to be more accurate it's when the sun is in the southwest that it is hitting my house walls.

I'm interested to know what people think about building on a northeast-southwest axis, with shade trees to the southwest side. Any thoughts on this one folks?

[Naam]

that is an incorrect assumption. as the "long" sides have to take a big heat load from in the mornings and late afternoons when the sun is for a long time "low" whereas the heat load from the south is less due to the sun standing "high" in tropical and subtropical countries.

I have yet to see a source mention this factor, but it is a tantalizing counter argument to ponder. It would be nice if someone made a calcultor for this like they have for solar panel pitch and such that takes into account all the various factors that could influence making this call.

you need a source as much as you need one to know that "two plus two equals four". logical thinking and knowing at what angle the sun shines at what time on the east, south or west part of a building is sufficient. if you don't know the latter just watch the sun during various times of the day (assuming you live Thailand or another tropical or subtropical country). results from Scotland or Northern Norway are not relevant!

Edited April 5, 2010 by Naam

[lannarebirth]

My observations from spending time on many parcels of land here. Orient your house to take full advatage of local and distant views. Orient to natural water features. Limit size of SW and west facing windows. Insulate your ceiling well and some thick Qcon style blocks facing south and west would probably be an advantage. The greatest heat I experience, both ambient and radiating is in the late afternoon hours when SW and W facing surfaces are most heated. Good tree placement will take care of some of these issues.

Edited April 5, 2010 by lannarebirth

[bifftastic]

To the OP,

Is there a temple nearby? That might dictate the bed location within the rooms and therefore maybe the location/placement of the actual bedrooms. My friend's bed had his feet pointing towards the temple (nearly 1km away but visible over the fields) and he was strongly urged to change his design by the builders (and the wife) to ensure that this wasn't the case!

For my preference, I love a sunset (never up to see the sunrise) and so have a western facing terrace/decking + purchased 5 mature trees to provide ample natural shading for the house.

Cheers

James

Thanks James,

haven't got the land yet but it will be near where g/fs' sisters house is, so the Wat is kinda diagonally about 1km away, do a left then a right on the main road and it's on the left, but yes, i'll be sure not to point my feet at the Wat

[bifftastic]

My observations from spending time on many parcels of land here. Orient your house to take full advatage of local and distant views. Orient to natural water features. Limit size of SW and west facing windows. Insulate your ceiling well and some thick Qcon style blocks facing south and west would probably be an advantage. The greatest heat I experience, both ambient and radiating is in the late afternoon hours when SW and W facing surfaces are most heated. Good tree placement will take care of some of these issues.

Thanks, some very good advice there.

[jubby]

Chiang Rai whilst not unique , is different to more southerly parts of thailand re climate.

if your out in the sticks its worth taking advantage of the predominantly southerly winds.

I'd say face north and have a lot of shade for the southerly windows. perhaps an extention of the roof to the south.

If in a built up area then its less important perhaps. our place more by accident than design is very cool. we only need Aircon perhaps 1-2 months a year to sleep.

[craigt3365]

Considering the temps I just noticed in the North, I would make sure whatever you do, have lots of shade. Either trees or large overhangs. Keep the sun out of the inside of your house!

Our house is just South of Pattaya. It faces pretty much south and west. Horrible. There were two small patios when we purchased the house. The sun beat into the house terribly...both in the AM and in the PM. We have added a very large patio to help keep the sun off the house...and are planting trees now to also help.

If I had it to do over, I would definitely not have my house face that direction. Before the extended patio, the sun came in through the large bedroom patio doors and hit the back wall! In the AM, it came in about 2 meters into the dinning room (only a small overhang there initially).

I would also do double block insulation...but a large veranda is perfect if you really want to face south or west....

[bifftastic]

Considering the temps I just noticed in the North, I would make sure whatever you do, have lots of shade. Either trees or large overhangs. Keep the sun out of the inside of your house!

Our house is just South of Pattaya. It faces pretty much south and west. Horrible. There were two small patios when we purchased the house. The sun beat into the house terribly...both in the AM and in the PM. We have added a very large patio to help keep the sun off the house...and are planting trees now to also help.

If I had it to do over, I would definitely not have my house face that direction. Before the extended patio, the sun came in through the large bedroom patio doors and hit the back wall! In the AM, it came in about 2 meters into the dinning room (only a small overhang there initially).

I would also do double block insulation...but a large veranda is perfect if you really want to face south or west....

yep, definitely going for the overhanging roof, it may be cooler up north but only in the mornings and evenings, still gets plenty hot during the daytime, I'm not there now but the mrs reckons I'll be 'farang suk' if i stay outside too long in the afternoon!

Double block walls too, not just for the heat but the noise of the <deleted> dogs and chickens!

I reckon the outside patio type area will still have an overhang protecting it and will probably face east and the bathrooms will be at the west end and have no windows, west north and south sides will have a perimeter wall to shade them so the blocks don't soak up the heat like a storage heater. If I want to go out in the sun I can go out somewhere, need the house to be as cool as possible, having said all that i'm sure she'll still complain about being cold! At the moment, when she's using the washing machine (outside) and waiting for it to finish she stands in a little triangle of sunshine cos she gets too cold in the shade!

[craigt3365]

That's great...love the comment about the dogs and the chickens! I lived downtown Bangkok a few years ago and could still hear a few!

[Naam]

Double block walls too, not just for the heat but the noise of the <deleted> dogs and chickens!

because it's the walls and not the windows which let the noise of the <deleted> dogs and chicken through

[bifftastic]

Double block walls too, not just for the heat but the noise of the <deleted> dogs and chickens!

because it's the walls and not the windows which let the noise of the <deleted> dogs and chicken through

well, yes, noise will come in through the windows but if I have single block walls with no cavity they'll get hot, as the rooms under her sisters house do currently, also they have those vented blocks at the top, presumably to let some air in, they also let the mosquitos and the noise in! Double glazed windows will, I know, still let some noise in but given that the area is a lot less than the walls, <deleted> chicken/dog noise will, hopefully, be reduced. And the bedrooms will be in the middle of the house and only have small windows.

I am not hopeful for a total <deleted> chicken/dog noise-free environment, only for the feeling that the <deleted> chickens/dogs are not actually in the room with us!

[xerostar]

Bifftastic, having read your replies it seems to me that you may not be aware of the best alternative to concrete blocks.

Concrete blocks are cheap, but they absorb and hold a lot of heat.

Why not use Superblocks or Q-con blocks?

They are light, easy to lay and they have great insulating properties both against heat and sound.

They come in large sizes so you can build a wall to full height in a 1/4 of the time it takes to build a concrete block wall.

The method does not require mortar between the blcks, just a thin layer of adhesive, making them easy to lay even for an amateur.

Because of their excellent insulating properties, it's not neccessary to build a double wall.

We used them for our house and shed as well as the main perimeter wall.

I can say it was one of my better decisions, despite the other bad choices I made in designing our home.

[bifftastic]

Bifftastic, having read your replies it seems to me that you may not be aware of the best alternative to concrete blocks.

Concrete blocks are cheap, but they absorb and hold a lot of heat.

Why not use Superblocks or Q-con blocks?

They are light, easy to lay and they have great insulating properties both against heat and sound.

They come in large sizes so you can build a wall to full height in a 1/4 of the time it takes to build a concrete block wall.

The method does not require mortar between the blcks, just a thin layer of adhesive, making them easy to lay even for an amateur.

Because of their excellent insulating properties, it's not neccessary to build a double wall.

We used them for our house and shed as well as the main perimeter wall.

I can say it was one of my better decisions, despite the other bad choices I made in designing our home.

yes you're right. I wasn't aware of them. I'd heard them referred to but didn't realise they were that different. I just thought they were slightly better than your bog standard block. They sound great. Can they be sourced readily in thailand?

[xerostar]

Yes they are readily available.

Now you get to use Thaivisa forum's search function!

Just type in "super block" and you will find many previous threads discussing what you need to know.

Here is a link to the Superblock company that will give you all the technical/engineering info on their products:

http://www.superblockthailand.com/service.html

Additional to this you can do a similar search on Google and come up with even more information!

That should keep you busy for a few weeks!

Cheers

[bifftastic]

Yes they are readily available.

Now you get to use Thaivisa forum's search function! woohoo lucky me!

Just type in "super block" and you will find many previous threads discussing what you need to know.

Here is a link to the Superblock company that will give you all the technical/engineering info on their products:

http://www.superblockthailand.com/service.html yep, thanks, I found that after reading your earlier post

Additional to this you can do a similar search on Google and come up with even more information!

That should keep you busy for a few weeks! indeed it will

Cheers

I saw an episode of one of my favourite TV programmes 'Grand Designs' where they follow people through their house builds, and they used these blocks, the walls shot up so fast and the builders loved them, they could saw them off to the length they wanted and just chucked the walls up in a few days! They also talked about their insulating properties and I remember being impressed, now I'm double impressed that they can be bought in Thailand! Just got to find them in Chiang Rai somewhere....

So, you're happy with the insulation (both heat and sound) that they provide in your house?

[xerostar]

Yes, except that the concrete floor is radiating infra-red all night and the superblocks keep

the air warm by not allowing any heat to penetrate the outside-facing walls.

I set up 3 digital thermometers (dual readout) with the sensors placed:

a) on the floor under a cupboard (floor temp)

in the ceiling space

c) hanging outside on the verandah

All three thermometers showed the inside room temp. as well as the remote sensor temp.

That's how I found the tiled concrete floor to be the culprit.

It always shows a temp of 29 C +or- 1 degree (that may or may not be the actual ground temp)

Whereas the ceiling air temp was usually a few degrees higher than the outside air temp (as expected).

The Ceiling has glass wool bats fitted for insulation. I would have preferred the blow-in CoolnCosy insulation but the cost

was too high for my budget. The blow-in type gives a more hermetic seal, whereas bats leave small gaps where heat can penetrate.

If it's cool outside then I just need to ventilate the rooms as much as possible. (windows open and fans blowing)

If it's hot outside then only the aircon makes any difference to room temp. (obviously)

If I had used superblocks over the floor of each bedroom (or the entire house) I think it would be a much cooler house.

The sound attenuation is very good. With only a single wall between bedrooms,

I used the 60cm x 20cm x 13.5cm (thickest available) so as to get best possible strength and insulating properties.

That thickness also matched the thickness of the square concrete columns we used.

We used columns at 3M intervals although with Super blocks, we could have done without any columns at all.

However our steel roof frame is welded to the top of all the columns (the reo sticks out at the top) and since we are in an area exposed to strong winds I'm pleased to say our roof has not moved even in cyclonic wind gusts during storms.

We used corrugated steel sheets for the roof. (with alufoil/tar underlay)

We have never had any leaks. The steel sheets heat up quickly but also cool down quickly

so they are fairly neutral when it comes to keeping a house cool.

In contrast the heavy fibro roof sheets can hold heat for a few hours after nightfall.

Worst are the ceramic clay tiles which can radiate heat all night long.

Either way good ceiling insulation is obligatory.

[Naam]

So, you're happy with the insulation (both heat and sound) that they provide in your house?

Xerostar has given excellent advice mate! there's nothing better than gas concrete blocks. but make sure the builder, respectively his masons know how to handle them. the (special) mortar is NOT used "thai style", i.e. 2-2.5cm thick but only a thin layer of 2-3mm. the picture below shows how it should NOT be done (two much mortar, blocks soak up too much water!). for my house i haved used exclusively super block (outside and inside walls). if you want a near perfect insulation then built double outside walls (closed on top). if the latter is not done properly the air cushion between the two walls renders only a fraction of the insulation.

[Naam]

1. The Ceiling has glass wool bats fitted for insulation. I would have preferred the blow-in CoolnCosy insulation but the cost

was too high for my budget. The blow-in type gives a more hermetic seal, whereas bats leave small gaps where heat can penetrate.

2. I used the 60cm x 20cm x 13.5cm (thickest available) so as to get best possible strength and insulating properties.

3.Either way good ceiling insulation is obligatory.

1. to the best of my knowledge blown-in insulation of any kind is not available in Thailand. if you know a source please let me know.

2. in the meantime 25 as well as 30cm thick blocks are available.

3. BINGO!

[Naam]

Yes, except that the concrete floor is radiating infra-red all night...

is the slab poured on the ground or raised with stilts and crawl space?

[bifftastic]

Thanks for the reply, very informative.

So your concrete slab floor extends outside the house thereby transferring the heat inside, which is then trapped by the insulating properties of the blocks?

I am mindful of some recording studio construction techniques where adjoining rooms have distinctly separate floors, ie. although they are next to each other, in order for vibrations, and therefore sound, not to be transferred, they are in fact 'islands' structurally. I know the physics of heat transfer are different but similar principles can be applied. If the slab floor of the interior is separate from any concrete or paving that is in direct sunlight that should help to prevent the outside heat from radiating through my house via the floor. I'm also leaning towards the overhanging roof concept to shade an area around the whole house.

Are your outside walls superblock too? Or just the internal bedroom walls?

With regard to roofing, I would imagine the clay tiles would be almost constantly warm if not very hot. What do you reckon this roof has, similar to yours?

[bifftastic]

So, you're happy with the insulation (both heat and sound) that they provide in your house?

Xerostar has given excellent advice mate! there's nothing better than gas concrete blocks. but make sure the builder, respectively his masons know how to handle them. the (special) mortar is NOT used "thai style", i.e. 2-2.5cm thick but only a thin layer of 2-3mm. the picture below shows how it should NOT be done (two much mortar, blocks soak up too much water!). for my house i haved used exclusively super block (outside and inside walls). if you want a near perfect insulation then built double outside walls (closed on top). if the latter is not done properly the air cushion between the two walls renders only a fraction of the insulation.

Thanks Naam, I checked out the superblock and q-bloq websites and they have guide pages showing how to use their blocks, first course on a thick layer of mortar (some other posts recommend a concrete 'curb') and adhesive applied in thin layers for the rest. If they're laid with as much mortar as in the picture it would mean you have walls with the properties of the mortar rather than the blocks! Weakest link in the chain syndrome.

The double outside walls sound like the business, I can understand the importance of closing the top of the walls properly.

It sounds like what is required is separation of the interior (as far as possible) from any outside radiation of either heat or noise. Am I right in thinking that even if the floor slab doesn't spread outside the area of the walls, if it is poured directly onto the ground the heat will radiate into the house directly from contact with the earth? Hence your question regarding stilts and a crawl space, minimising the contact with the ground and thereby the heat transfer?

Cheers,

Biff

[xerostar]

The last few replies have raised some good points.

My house is on a concrete slab on the ground that has the same footprint as the house with verandah.

I thought the verandah would give enough shade but unfortunately it only shades well at midday.

It should have been built on stilts - even if they were only 30 cm high.

(Then the problem is domestic and wildlife making homes underneath)

High stilts so as to form a garage or carport seems like the best way to go.

That would eliminate the heat transfer from the ground.

Next the roof needs to be extended a long way beyond the outer walls to give sufficient shade to the concrete slab.

Hhmmmm .... It starts to look like a traditional Thai house!

[Naam]

The double outside walls sound like the business, I can understand the importance of closing the top of the walls properly.

It sounds like what is required is separation of the interior (as far as possible) from any outside radiation of either heat or noise. Am I right in thinking that even if the floor slab doesn't spread outside the area of the walls, if it is poured directly onto the ground the heat will radiate into the house directly from contact with the earth? Hence your question regarding stilts and a crawl space, minimising the contact with the ground and thereby the heat transfer?

Cheers,

Biff

that is a misconception Biff as the soil under the slab is definitely cooler than the ambient air temperature. if the slab stretches beyond the outside walls and that part has direct exposure to the sun a wee bit heat transfer might occur. but my guess is that it is not noticeable. real heat transfer you have when the house is on stilts and hot air can flow underneath. the (often mentioned) thai fairy tale that a house on stilts is "cooled' underneath by ambient air is... a fairy tale!

[Naam]

Next the roof needs to be extended a long way beyond the outer walls to give sufficient shade to the concrete slab.

not only to the slab but to prevent (as much as possible) direct sun on the walls. but there are limits when you build (like me) a rather big single story home. in order that you don't hit your head at a long roof overhang the roof gradient has to be lowered and that might cause leakages between the roof tiles when heavy rain is combined with high winds.

here's an interesting story on an energy efficient home. in a former life i took up a job in West Africa. when i arrived the house in which i was supposed to live later was already in a rough construction state. going through floor plans i shook my head and muttered about the bloody native architect. i want to jump what i did every evening with a 10-pound sledge hammer and a sign "do it again!" and concentrate on "energy". living room combined with an open dining room was around 80m² and i calculated that two 24,000 btu/h aircons were necessary for an adequate cooling to 26ºC at outside temperatures of 35-40ºC. the builder provided the necessary openings to slide in wall units later. to make a long story short. 24k aircons were not available so i installed three 18k units, one in the dining room and two in the living room. the (big bedrooms got 12k units). living in the house i realised that a single 15k unit was enough to cool the 80m².

reasons: the longish rectangle house was placed in exactly east-west direction. bedrooms east, garage storage and utility room west. the roof was highly polished corrugated aluminium (looked awful!) reflecting sunlight like a mirror with an overhang of nearly 2 meters. all windows were 1 meter recessed (outside a planter) and never got a single sunray. the ceiling was some sort of 2 cm thick cardboard without any insulation in the attic. but ample air inlets and a 30m long roof vent provided excellent ventilation. and soon i stopped bitching about them native architects.

[xerostar]

What if I believe in fairy tales?

What if the ground temperature is higher than the air temp?

I suppose it depends where your house is situated, what time of the day, season etc.

e.g. if your house is close to a wet rice paddy and has damp soil, I'd imagine the ground would be cool due to surface evaporation, but the humidity would be higher in those places.

But our house is up on a hill and there is no water for miles around, the soil is baked as hard as granite.

The ground is very hot. The dogs won't lie on that ground, they look for a spot in the shade that catches any breeze.

They prefer it if you give them a trampoline type of bed "off the ground".

That's when it would help to have the house above the ground or better still, sitting on a layer of insulating material.

That idea of having the house on its own pad, separated by insulation from the surrounding verandah would be worth a try.

In any case, anything that prevents the suns rays from striking the house and surroundings or being reflected off the surroundings is going to help keep the house cooler.

[bifftastic]

Next the roof needs to be extended a long way beyond the outer walls to give sufficient shade to the concrete slab.

not only to the slab but to prevent (as much as possible) direct sun on the walls. but there are limits when you build (like me) a rather big single story home. in order that you don't hit your head at a long roof overhang the roof gradient has to be lowered and that might cause leakages between the roof tiles when heavy rain is combined with high winds.

Maybe if the roof had two pitch angles, one higher, above the house itself, then a lower pitch for the overhang? Kinda like a sun-hat with a brim

I agree with the 'fairy tale' g/f's sisters house is wooden on stilts and is hotter then a really hot thing when it's hot and colder than a really cold thing when it ain't! IF the air is cooler it must be by about a tenth of a degree at most, as it's just been heated by the sun before it blows under the house, and then, of course, it doesn't exactly blow, it kinda passes by at best.

I suppose if you were near the shore and lucky enough to have a constant breeze then it might have some effect but I don't think it's enough to have any real effect, more useful in those houses is the fact that everyone can hide underneath the house out of the sun, cos it's like a wooden oven upstairs!

Even though the house is right on the northern most border with Laos and she's from Korat, she's complaining it's too hot. Mum's visiting from Korat and she's too hot, kids are too hot, everyone's too hot.

Electric bill has gone up from 500 baht when I was there in January, to over 1,000 due to multiple fans, which only blow the hot air around anyway!

I think the trick is to (try) and keep direct exposure to sunlight at a minimum and insulate well any areas that protect you from it (mainly the roof) and, if possible, take advantage of any naturally occurring ventilation, like the idea of the 30m roof vent from your African house Naam.

As I said right at the beginning of this thread, this is all a very long way off at the moment, but I've learned a lot already from everyone who's posted here, so, thanks keep it coming, hopefully others can learn something useful too.

Here's what I've come up with so far, it's just a first draught so please, pick holes as much as you like

The terrace or patio is facing East in this illustration, and the perimeter wall is designed to protect 3 sides from some sunlight, the roof overhang will create shade as far out as that wall too. It's a basic drawing and doesn't have many of the details I know it will need but I wanted to get some ideas down.

Cheers

Biff

[kokesaat]

Our house is E-W axis with the carport on the western end to deflect the afternoon heat. We have a wrap-around porch around the south and east sides of the house along with a large overhang. If your porch is less than 7 feet wide, there's not much you can do on the porch.........9-10ft wide gives you a nice outdoor space.

Despite our best efforts, the morning sun is a killer.....if we had to do it all over again, we'd put up a larger east overhang with an extended sloped roof to deflect the sun.

At all costs, keep the sun off your windows (priority 1) and walls (priority 2). The sun never hits our southern, western, and northern windows. That helps.

We have a white rolled steel roof with insulative barrier attached, along with 4" of ceiling insulation. When we remodel in another year or two (our house is 12 years old), we'll add another 6" to the ceiling insulation.

If your house is 2 story, you're out of luck with keeping the sun off the windows.

If your house is raised off the ground (ours is cement and is raised one meter), put your water tank under the house. You'll be especially happy to have cool water in the hot summer months.

[Naam]

Our house is E-W axis with the carport on the western end to deflect the afternoon heat.

1. We have a wrap-around porch around the south and east sides of the house along with a large overhang. If your porch is less than 7 feet wide, there's not much you can do on the porch.........9-10ft wide gives you a nice outdoor space.

2.Despite our best efforts, the morning sun is a killer.....if we had to do it all over again, we'd put up a larger east overhang with an extended sloped roof to deflect the sun.

1. ideal!

2. the reason is the higher relative humidity in the mornings which amplifies sunrays.

in the south-west of the U.S. as well in QLD, Australia you find the ideal house. it's called "Queenslander" which has huge wrap-around porches attached to all four sides.

[splitlid]

biff. i think you need to rip it up and start again.

you are designing a place to live and enjoy, at the moment it looks more like a dark, depressing, unhealthy mess.

try again please.

think about room relationships

light into the rooms (as i said before you should be looking at a min 10% or the rooms floor area) via windows, etc.

flow

blah blah blah

[Naam]

...the perimeter wall is designed to protect 3 sides from some sunlight

to me it seems your land is too small for that dominating wall Biff. people living in the house will suffer from claustrophobia.