SDN - Design a house

[Korto]

It's been a trifle warm around here lately, as in over 40C, and our house has a lovely ability to keep the heat in. Last night it was 34 inside the house at 2.30AM, and was still 31 at 6.30AM (shit...is that all the sleep I got? Fuuuck...).
So basically I've had it up to here with the heat.

The house is old. Quite old (amendment: quite old for Australia. I don't want to hear about someone in Europe living in a place built by the bloody Romans), old enough that electricity was a later modification, and so it has a few old bad ideas (lack of insulation), and what few good ideas they had were ruined by later modifications (the verandah sheltering the windows has been closed in, transforming it into a solar oven that heats the rest of the house).

In two more years, we'll have paid this hovel off, at which point we'll be able to save some money up to do something about the place. Now, the house is so old that it's no longer worth trying to fix it up, so we're planning to knock it down and rebuild in its place (besides, I'm looking forward to watching a bulldozer go through the house. Please, tell me there'll be a bulldozer).
I've been working on a design lately, which strangely enough has largely concerned itself with keeping cool during summer. I'm trying to avoid air conditioners, and look a lot at design and passive cooling. I've got a few ideas, but my ideas can sometimes be either (a) too expensive, (b) stupid, or (c) both, so I figured I'd open the discussion up.

Design Problems
1) Design for the long-term. I want this house to be designed to stand for over a hundred years. Whether it does is up to whoever owns it at that point, but that's got nothing to do with me. That means Global Warming (GW) has to be accounted for.

2) The HEAT! I'm sick of it! Average temperatures during summer are in the 30s (which are OK), peaking to 40s, and with about a 10C drop overnight. With GW, I'm expecting it to get hotter.

3) The property is at the bottom of a small basin, in a flood zone. Under heavy (maybe once ever 4 years) rain, we get two feet of water in the yard - the council has done extensive work redirecting the run-off from the surrounding higher land behind us to a large sports field area that acts as a sump. Before that was done, I'm reliably informed the water was over 4 feet high and came into the house (this trapped water effect was actually because of a recent-ish set of flats blocking the natural drainage, it wasn't like that originally).
This water can take over a week to subside.
However, the worst flood on record rose to 2.4 metres, in the 1960s. There's a marker on a powerpole just outside. I measured it. It happened once, it can happen again.
I'm expecing GW to make this worse.

4) FInances. We're not rich. If we were, we'd say "Fuck this" and move to somewhere cool. Like a castle in Scotland. We need to do our best to keep the build costs down, BUT ALSO the running costs down (two aims that are frequently contradictory).

5) I would prefer not to eat up more yard space then the house already takes.

Property Layout
The front of the house, facing the main road, faces basically north. A bit NNW.

The front of the property has a very small yard, a footpath, and then the main arterial road. This road is built up 1.5m above ground level (just measured it. Hey! It's sprinkling outside! And today's going to cooler...mid 30s...and probably going to be as humid as fuck), and there is no road access there. The back yard is medium-sized, and there's a laneway behind it for street access. On the sides, there's significant yard space on the east (over 8m), minimal on the west (3.2m).

The house itself is basically a rectangle and take up 12 x 8m (including the verandah).

My Ideas So Far
Put the house up on stilts, 2.5 metres above ground level. Nothing important to the house integrity is to be below there. This then creates a problem that hot wind under the house will heat the house, so the area underneath is to be enclosed with good insulating material that would break away in a serious flood and wont be completely ruined by immersion in a few feet of water for a week. I'm thinking expanded polystyrene (EPS), with render over the outside. Inside, I want a thermal mass wall, so I'm seeing lots of shelving, packed with 3 litre milk bottles full of water. Solid walls of the damn things, creating a wall of water from floor to ceiling 150mm thick, and then covered over with something (don't know what, will come up with something, not important now). The shelves will sit (not secured) on little ledges on the stilts, so that if there is a serious flood, the flood water will break the EPS and push the bottles and shelves out, and leave the stilts unmolested.
It would be nice to have air come into this basement via underground pipes, for added cooling effect, although I do have concerns about what if they get flooded. Perhaps if the outside end finished a few metres up in the air? With netting to keep out the wildlife, and a rain-cap.

The house proper is post-and-beam construction, with no load-bearing walls. The walls are made of strawbale, thickly rendered inside (acts as a thermal mass); this enables them to insulate from the outside, and moderate inside. It looks good, and I think it's within our capabilities to do the walls ourselves.

Cathedral-style ceiling. I've gained the impression the taller the ceiling, the cooler the room, so effectively no ceiling, just a roof. I like the bare-rafters look, anyway. It may be a dutch-gable roof, with large air-vents at the gable ends, or maybe a clerestory roof with windows that can be opened to allow heat out. I'm leaning towards the clerestory roof, as the windows will also supply light into the house (one of the things that annoys me about this house is how I've got to have lights on during the day).

The walls don't go all the way to the roof, only 3 metres or so, allowing air circulation, and light from the windows.

A cantilevered verandah that completely encircles the house (no posts to the ground). Multiple doors to it, so someone can go from their bedroom to the verandah. No way to the verandah except through the house (security).
I'm speculating that I may not need a gutter if I can drop the water 1.5 metres away from the house; gutters are a pain, they generate work.

An internal staircase goes from the basement (and front door) up to the internal front door of the house. Cool air from the basement can come up this into the house, to replace hot air lost above.

There will be solar electricity, but possibly not hot water as I'm wanting instantaneous electric, and I feel the solar loses me the temperature control that instantaneous electric gives (we've got a modern instaneous in the bathroom. You want the water 45C? Set in 45. You want 34? Set in 34. It's brilliant. But it can't cool water, so if the water's too hot already...). Mind you, if new cold was introduced before the instantaneous, it would solve that problem, and reduce the hot water used from the solar storage. Hmmm....

A sketch:

Huh. Probably should label my stuff better.
OK, the top is the ground floor, with the verandah. You can see the bedrooms, bath, toilet, etc. Kitchen, dining, lounge is open-plan.

The ticky lines rule off metres.

Under that is the basement. You can see the bottom front door, and stairs. That square marked off is the laundry. Therefore there'll be a door to the backyard around here. The basement will also be used as a workshop and gaming space, possibly even to store junk, but nothing we would cry about if it got flooded.
The laundry will probably have a laundry chute from the bathroom located conveniently above.

Underneath that is a side and front view, with a dutch gable roof

Last Words
Don't panic. I fully intend to talk to actual trained people when it comes to that, with letters after their names and everything, but it's a few years away at the moment. I'm just trying to sketch out what I want in advance.

Anyway, it's fun.

[Jaepheth]

My dream house is an earth sheltered home. (Build a concrete/steel house and then bury it under a hill)
The rooms would be arranged around a central cloister that has a large domed skylight with retractable shades.



(Mine wouldn't have as much exposed outer wall as this one. but it gives you an idea of what I'm talking about.)

[Korto]

Oh yeah, I love those underground homes. Bit pricey when I was looking, but very cool.
Not very suitable for a flood zone.
Would the skylight be translucent, or clear so you could see the sky?

[Simon_Jester]

One concern I note is "the higher the ceiling, the cooler the room;" I'm not entirely sure it works that way. The incoming sunlight will heat up the roof. If you've got good ventilation under the roof that may not matter, but it won't help. At least with ceilings, you can realistically hope to get the temperature of the ceiling into thermal equilibrium with the temperature of the room you're in.

[Starglider]

Straw bale plus wood frame sounds like a fire hazard. Plastic bottles produce nasty fumes in a fire as well. I would build the lower plinth out of watertight reinforced concrete, so that it is an actual usable basement for storage / home cinema / gym. Ventilation pipes rising above any plausible flood level is correct. If you insist on post and beam for the upper house, at least use reinforced concrete or failing that mild steel columns. Reinforced concrete is quite amenable to self-build if you have the minimal carpentry skills requires to errect formwork and place rebar. If you don't have gutters, and the area isn't fully paved/drained, you should put in a soak-away trench to avoid ground erosion (just a trench full of gravel along the eaves line). The stairs as designed appear to rule out access to the house by wheelchair. While not a showstopper, it would be sensible to allow for possible addition of a wheelchair ramp later, in case someone in your family becomes disabled.

I am actually considering flattening our house and building a new one as well, but not for at least four years. My plan is to bisect the conventional pitched roof chalet bungalow plan with a central hall of catenary arches, with (self-cleaning) glass roof in-between. There would be a basement level under 2/3 of the floor plan, such that the hallway is a three-story space with a passenger lift, walkways with translucent glass floor, and plants below. The basement level would contain a lounge area and an underground passage connecting to the detached earth-sheltered triple garage (upper level of; the garage also has its own basement). The eaves would be extended, to increase usable upper floor space, but it would not be a veranda; rather I would have a row of support columns in front of a glass inner wall, with roll-down electric shutters in the overhang. There would be wide aspect arches between the outer pillers and all the walls and arches would be stone clad; upper floor end bedrooms would have arched dormers mirroring the main arched roof. Finally, I would add two small octagonal towers on the side adjacent to the tree-line, and hip the roof ends. Construction would be all waterproof cast in situ reinforced concrete (solid floors, plus primary roof supports), with stone curtain walls, roof supports from CNC bespoke galvanised steel trusses (quite cost effective now; wood is outmoded), dark clay tiles (with hidden valley in the roof to increase upper floor area without raising the roofline, which the council are really strict about).

[Zaune]

I remember hearing a bit about straw-bale housing when my dad was working for a non-profit dealing with energy-efficiency stuff. It can be made to work, and incidentally makes really good insulating material for the price, but you'd need to surround the straw with something airtight and flame-retardant.

[Elheru Aran]

I thought for a moment you were in NZ, and was about to make some crack about how you should dig yourself a Hobbit hole, but then I noticed the 'flooding' part...

Anyway. Vernacular architecture in climates similar to yours is what you're looking for. There's been some work in the southern US on building cheap houses for the economically disadvantaged, using local historically proven building principles and materials. Damned if I remember the name of that program, though. It's in Alabama, I want to say.

[General Zod]

What's your budget? You need to be able to plan for the house you can afford.

[General Zod]

That said . . . a proper HVAC with some electrical re-tooling could go a long way to improving the place. It might run you upwards of $10k to install a solid system with the necessary infrastructure modifications.

[Korto]

OK, let's attack this in order. Incidentally, today is a beautiful cool day, overcast, mid-twenties at the moment. I'll enjoy it while it lasts, which will be, according to the forecasts, today.

One concern I note is "the higher the ceiling, the cooler the room;" I'm not entirely sure it works that way. The incoming sunlight will heat up the roof. If you've got good ventilation under the roof that may not matter, but it won't help. At least with ceilings, you can realistically hope to get the temperature of the ceiling into thermal equilibrium with the temperature of the room you're in.

There's a risk I'm mis-using that rule-of-thumb, because the people were really talking about normal ceilings, not cathedral, and I've just extrapolated. The idea is that with the higher ceiling, there's more space for the heat to rise before becoming trapped. What I didn't mention was that the higher the ceiling, the more expensive it is to heat or cool (ie, AC), because there's not only more volume, but a lot of that volume is up out of where the people are. As I would like to design a house that doesn't need AC (experts keep on saying it can be done), it didn't seem relevant.
Cathedral rooves, according to online sources, can be good, and they can be baaad, and it seems to depend on ventilation, but most vitally, insulation. Without the large ceiling cavity space, the insulation is often crushed to fit, meaning it doesn't work and the roof just picks up all the sun and radiates it in. It can, however, be done properly, and forewarned is a chaos mutant.

Starglider: Strawbale is surprisingly fire resistant, and has been tested by the CSIRO and approved for bushfire areas. Here's a government web page on the material. The trick is the straw is tightly packed with very little air contained, and then is covered with a thick layer of fire-proof render. It is in fact more fire-resistant than many standard materials.
I have a concern about a watertight sealed basement at ground level if there is a real flood, say a couple of metres. My concern is the water would be able to exert so much force it'll be able to do real structural damage. What I'm doing with the EPS and fall-away water shelves is trying to design something that will just break away leaving only posts behind.
I don't believe a thin plastic container with three litres of water in it poses a fire-risk. I wouldn't be surprised if it would be a net benefit, but it can be investigated. There would be the possibility of inbedding the bottle in a mud-brick. These bricks would be ruined by any water-immersion, but be easily replaced.
I'm thinking steel for the posts and frame, although I would investigate concrete; termites can get fucked.
For where the water falls off the roof, I was thinking of some kind of gravel, to break the water inpact and stop erosion. There's turf reinforcement grids, something like this could be helpful, preferably with some kind of tough grass growing in it. Although if I decide we want a water-tank, suddenly guttering would look a lot better.
Yeah, I never thought of disabled access. A ramp up to the ground-floor door wouldn't be a problem. Inside, the stairs should be able to be made to easily convert to take a stairlift if needed. I don't see why not. Just have to remember to specify it.
Starglider's House: You and I live in different financial worlds. We really do.

Current favoured practise with render for strawbale is lime or earth. Concrete doesn't allow the straw to "breathe", and so traps in moisture. Straw does have problems in 'wet rooms', such as the bathroom and kitchen, but there are ways to deal with that.

Anyway. Vernacular architecture in climates similar to yours is what you're looking for. There's been some work in the southern US on building cheap houses for the economically disadvantaged, using local historically proven building principles and materials. Damned if I remember the name of that program, though. It's in Alabama, I want to say.

I should do that. Not really sure where to start, to find an area with the same climate. Then, even if their traditional housing is unsuitable, it may have principles that can be used.

And Zod, our budget is, well, we could probably borrow about $200,000 once our current mortgage is paid in two years. Also, once it's paid, we could save up some money first. But, $200k is a reasonable assumption at this point.
Renovating this house is not a good option. It has issues. Think of it a bit like an old car, that you could keep on getting fixed, but it'll be cheaper in the long run to scrap it and buy a new one.

[madd0ct0r]

Hey Korto,

info needed:

1) climate info - what's the summer-winter cycle like, and what's the daytime to nighttime like in summer and winter?
1b) as part of that, humidity. You talked about a 10deg drop at night (from 40 deg to 30deg), which suggests a very humid cloudy area. Am i correct?
1c) How constrained is the plot (8m to the east, 3.2m to the west) and in which direction does the house face? - these are all about thinking about the heat load to balance, and where it can be balanced against. Thermal mass is useless when the temperature is always too hot. What do you use the yard for currently? What is its surface covering?

2) flooding. If you were uk based I could pull up the flood map for your area easily. Might be able to do so for austrailia, but I appreciate the records and detail might not be there yet. For the flooding, I'd advise splitting down into scenarios. A 1% chance flood up to a 20% chance flood. The latter you probably want no damage from, the former, well, you can see what the cost difference would be to design to ignore it or not.

http://www.bom.gov.au/water/designRainfalls/index.shtml and http://www.bom.gov.au/climate/ seem to have reasonable data maps, happy to help you pick out the key bits for your specific address.

3) other constraints: Particular for flood prone areas, how do the local sewer systems work? are there any rules on rainfall retention? are there any issues with fresh water sourcing? How much spare land around the proposed house is there?

4) what is the plan for the waste material coming off the old house?

5) How off grid are you aiming to go? The amount of solar panel (or not) defines the roof shape
---

It dosen't help on the flood side of things, but if the house was built to decent colonial standards, it might be salvageable. Exterior wrap in insulation sheet, restore the verandas and shading, ceiling fans. Ensure the loft cavity is very well ventilated, and then nominate an 'inner core' of rooms to be AC, with insulation and sealed construction for them.

[General Zod]

Does it really need to be two stories? I'm pretty sure multiple floors will actually make it more expensive than just spreading it out across a wider area. Assuming that's an option of course.

[Starglider]

Starglider: Strawbale is surprisingly fire resistant, and has been tested by the CSIRO and approved for bushfire areas. Here's a government web page on the material. The trick is the straw is tightly packed with very little air contained, and then is covered with a thick layer of fire-proof render. It is in fact more fire-resistant than many standard materials.

It will definitely rot if the render cracks. As you may have guessed I am not a fan of bioecosustainadegradability, which is another thing trendy architects tend to inflict on people for their own status points, or rebuilding bits of the house regularly, and many insurance companies would agree. In fact when I change insurance providers they start with 'is the house made of brick, concrete and tile' and if you say anything else it is a minfield of excess fees.

I have a concern about a watertight sealed basement at ground level if there is a real flood, say a couple of metres. My concern is the water would be able to exert so much force it'll be able to do real structural damage. What I'm doing with the EPS and fall-away water shelves is trying to design something that will just break away leaving only posts behind.

Weight or dynamic force of flowing water is not a significant factor. Standard 20mm R/C walls will resistant many hundreds of tons of earth load, given appropriate rebar (galvanised if you are really concerned about cracking); soil is over five times denser than water. For a sealed basement flotation (of the whole structure) does need to be considered, but that generally just means adding more cheap gravel ballast between the foundation slab and the floor screed (or tying the structure to foundation piles). Your structural engineer will check all this.

Yeah, I never thought of disabled access. A ramp up to the ground-floor door wouldn't be a problem. Inside, the stairs should be able to be made to easily convert to take a stairlift if needed.

For wheelchair access, beyond having an access ramp the key thing is clearances, particularly doors, turns and bathrooms. It is worth paying slightly more for wider doors, aside from anything else it makes adding/removing furniture easier.

Reversible ground-source heat pump is an option but not cheap.

[madd0ct0r]

Starglider: Strawbale is surprisingly fire resistant, and has been tested by the CSIRO and approved for bushfire areas. Here's a government web page on the material. The trick is the straw is tightly packed with very little air contained, and then is covered with a thick layer of fire-proof render. It is in fact more fire-resistant than many standard materials.

It will definitely rot if the render cracks. As you may have guessed I am not a fan of bioecosustainadegradability, which is another thing trendy architects tend to inflict on people for their own status points, or rebuilding bits of the house regularly, and many insurance companies would agree. In fact when I change insurance providers they start with 'is the house made of brick, concrete and tile' and if you say anything else it is a minfield of excess fees.

I have a concern about a watertight sealed basement at ground level if there is a real flood, say a couple of metres. My concern is the water would be able to exert so much force it'll be able to do real structural damage. What I'm doing with the EPS and fall-away water shelves is trying to design something that will just break away leaving only posts behind.

Weight or dynamic force of flowing water is not a significant factor. Standard 20mm R/C walls will resistant many hundreds of tons of earth load, given appropriate rebar (galvanised if you are really concerned about cracking); soil is over five times denser than water. For a sealed basement flotation (of the whole structure) does need to be considered, but that generally just means adding more cheap gravel ballast between the foundation slab and the floor slab (or tying the structure to foundation piles). Your structural engineer will check all this.

Yeah, I never thought of disabled access. A ramp up to the ground-floor door wouldn't be a problem. Inside, the stairs should be able to be made to easily convert to take a stairlift if needed.

For wheelchair access, beyond having an access ramp the key thing is clearances, particularly doors, turns and bathrooms. It is worth paying slightly more for wider doors, aside from anything else it makes adding/removing furniture easier.

Hey Starglider, you are right about the cracking - that's why most strawbale walls are rendered using limecrete or claymix - OPC WILL crack. I like strawbale, I'll probably use it for my own house, definitely so if I'm building on the east side of the UK, and have sufficient land to accept the wall thickness

Soil is NOT 5 times denser than water. Steel is. Concrete is 2.4 times denser than water. Soil 1.8-2.5, and even that is getting into rock levels. Soil imparts a lower load on a well designed wall, because the wall is designed to move a few mm at the top, allowing the triangle of soil behind to shift slightly. Thus, the wall is only supporting the shifted triangle, with the rest of the soil being in a stable embankment block. Water you don't have such luxuries.

Failure for the lower storey probably wouldn't be an RCwall snapping, it'd be buoyancy lifting the entire house off it's foundations, sliding under unequal weight of water or corners of the house being undermined by scouring (dependant on flood water speed of movement). Buoyancy is counteracted by oversized foundations to get a mass anchor of concrete under the house, but that's relatively expensive material wise.

[Starglider]

If you are seriously concerned about scouring under the foundation, the only solution is piling. A couple of dozen 10m deep steel-cased concrete piles would certainly do the trick, but would also consume about 20% of the budget. We are talking 'house is suddenly in the middle of a river' levels of water flow to get significant scouring though.

[madd0ct0r]

Nah, I'm talking about scour holes about 0.5m deep at worst at the corners of the house only caused by free flowing 1m deep waters. Sudden river syndrome is a possibility given the area's history, but given how much the landscape and river will have changed in 50 years it'd be hard to make a prediction - that's what central flood maps are for.

[Starglider]

Nah, I'm talking about scour holes about 0.5m deep at worst at the corners of the house

That's no problem for an R/C raft foundation. Just fill it with rubble (compacted) after the flood. Obviously it could be an issue for an unreinforced simple slab.

[Korto]

Hey Korto,

info needed:

1) climate info - what's the summer-winter cycle like, and what's the daytime to nighttime like in summer and winter?
1b) as part of that, humidity. You talked about a 10deg drop at night (from 40 deg to 30deg), which suggests a very humid cloudy area. Am i correct?
1c) How constrained is the plot (8m to the east, 3.2m to the west) and in which direction does the house face? - these are all about thinking about the heat load to balance, and where it can be balanced against. Thermal mass is useless when the temperature is always too hot. What do you use the yard for currently? What is its surface covering?

2) flooding. If you were uk based I could pull up the flood map for your area easily. Might be able to do so for austrailia, but I appreciate the records and detail might not be there yet. For the flooding, I'd advise splitting down into scenarios. A 1% chance flood up to a 20% chance flood. The latter you probably want no damage from, the former, well, you can see what the cost difference would be to design to ignore it or not.

http://www.bom.gov.au/water/designRainfalls/index.shtml and http://www.bom.gov.au/climate/ seem to have reasonable data maps, happy to help you pick out the key bits for your specific address.

3) other constraints: Particular for flood prone areas, how do the local sewer systems work? are there any rules on rainfall retention? are there any issues with fresh water sourcing? How much spare land around the proposed house is there?

4) what is the plan for the waste material coming off the old house?

5) How off grid are you aiming to go? The amount of solar panel (or not) defines the roof shape
---

It dosen't help on the flood side of things, but if the house was built to decent colonial standards, it might be salvageable. Exterior wrap in insulation sheet, restore the verandas and shading, ceiling fans. Ensure the loft cavity is very well ventilated, and then nominate an 'inner core' of rooms to be AC, with insulation and sealed construction for them.

I was hoping I'd attract you--I remembered you seem quite knowledgable about this kind of stuff. I think your work has a lot to do with construction?
Anyway
1) Summery and wintery? Not what you're asking, I'm sure, but I'm not at all sure what it is you're asking. I have, however, finally found some historical weather data for the area which may help.
1b) My approximation off the data I could find before was off. The average temperature fall overnight is 13C. Using some wet-bulb readings from that weather site (all available statistics button), the average humidity for the year is 68.5%, and is 66.4% for summer (December to Feburary)
1c) Those east and west distances are how much free space there is on the left and right of the house. The actual property itself is more like 20x30m, front is narrow end (it's never actually been surveyed, but that's about right). The house actually faces, assuming Google Maps has north straight up, pretty plumb north west (so I was wrong earlier. Shows what vague attention I applied to where the sun actually rose and set). Most of the yard is vegetation, with a garage and covered work area at the back at the lane. It's used for chickens, rabbits, lizards, possums, fruit trees, and my hammock. I find wildlife and wild greenery relaxing.

2) I'd enjoy finding out some specifics. Since we're on a river, rainfall isn't the only factor--there's water coming down the river, and water coming back up it (tides). Although my idea of lifting the house up directly gives me a lot of space underneath for things that either don't need or you don't even want in the house proper (like a good wood workshop), so I'm not seeing it as money wasted.

3) Ummm, a lot better since I got the pipes fixed? (Honestly, the pipe had collapsed, there was a subsidence hole in the backyard, shit backing up through the overflow into the yard. It was disgusting. Took out the whole length of old ceramic, replaced it with new plastic). Ummm, pipes join to a sewer main, goes to a treatment plant.
There are no rules about rainfall retention, and last I looked there was a subsidy to put in tanks. Fresh water comes out of the tap, from the town mains. I would prefer to just take the same footprint as the old house, giving about 8 metres on one side, 3 on the other, 2 at the front (this could be a problem with a taller house. Bruce the builder wasn't sure what the Council would think), and about 16 at the back.

4) None at the moment. Possibly get one of those demolisher/recycled materials guys to do the job? There's a couple around.

5) I would like to be able to supply my own power (we apparently use 13kWh/day at present), but I'm not addicted to the thought. There is a trend here, though, for grid power to be going up (over inflation), and solar is coming down.

Starglider, I will look into reinforced concrete walls. I do have fears about the cost, and the bouyancy thing sounds like another concern (funnily enough, I was going to wonder about bouyancy earlier, but chickened out because I didn't want to look stupid). It may be that any water deep enough to be a bouyancy problem is too unlikely to worry about and/or too much for someone to deal with with my limited budget anyway.

[Shroom Man 777]

It would be so great to somehow have a roof made out of mirrors - reflect that solar heat back to the sky, bitches!

[Korto]

Interesting idea, but we're in the flight path of nearby military and civilian airports. I'm not sure how they'll like the dazzle
Incidentally, Shroomy, my daughter has a stuffed seahorse that speaks a lot like you sometimes.

[madd0ct0r]

was hoping I'd attract you--I remembered you seem quite knowledgable about this kind of stuff. I think your work has a lot to do with construction?

There's more than enough for me to chew on there, but please please do not mistake the pontification of a guy on the internet for a local proffesional.

One further question - is traffic noise an issue? are you looking to pull the house back from the road?

[Starglider]

It would be so great to somehow have a roof made out of mirrors - reflect that solar heat back to the sky, bitches!

This is called 'painting the roof white'. Reflectance ~90% if you keep it clean.

[Korto]

Traffic noise isn't a worry. I used to live on an important work travel route, so here's quieter really. I also like how pushed forward the house is, it gives me a larger backyard to play with.

And a white, or at least light, roof would probably be very useful for a cathedral ceiling, where I've already mentioned insulation is an issue. A light ochre yellow would be nice.

[Elheru Aran]

Would a roof made of naturally white materials work? When I lived in Africa, one common roofing material was what my dad called 'asbestos tile'-- basically corrugated roofing made of some kind of cement-like material. Naturally, it was pretty light colored, and I imagine there was a certain degree of reflectivity.

I know there are metal roofs and such available in natural colors, but metal roofs also cost more to do right and will corrode if not protected and maintained, I imagine...

[madd0ct0r]

As it happens I'm in my father in laws house. This is based in central Vietnam. It's the middle of winter here, and therefore roughly the same temperatures and humidity as Korto described. The house is built on a similar size plot but is rather bigger then Korto's spec. Structure is rc col and slab with masonry infill. It is cool and airy in winter. The bedrooms need aircon in the summer, but that's 40 degrees at 90% humidity, there's not much you can do at that extreme.

The house was designed by my wife's cousin, an incredibly talented architect, credentials on request. Basically, don't give me credit for this design

Plan layout of the three floors.
https://drive.google.com/file/d/0B8jYpG ... p=drivesdk

The design is centered around encouraging hot air to move up and out while allowing indirect sunlight to filter down through the house to stop it becoming gloomy. Air intake from the garden is encouraged because that air is a bit cooler and fresher. The house is surrounded by 3-6 storey buildings so the garden is shaded most of the time. Floor finishes are ceramic tile everywhere, but wooden treads on the staircases and wood flooring in the air conditioned bedrooms.

Problems
: the light well is amazing but because the bathrooms are fully tiled and the lightwell is brick and plaster it also is an amazing sound box. No using the toilet in a subtle fadhion. In General the house is a bit echoey. The noise response could be improved.

:the top floor gets very hot. The drying room uses this, and the other rooms are not used daily. But unless you have a family altar, its lost space

: the layout is not optimal, but was chosen to allow the garden to be sold off at a seperate plot in the future. One reason for the limited windows.

: downstairs loo has no ventilation to the outside, just the kitchen

: the layout means the shower drains are long and on very slight slopes, combined with beach sand and hair they are at risk of getting blocked to easily for my liking.

: sustainability - concrete and brick and tiles not to great for embodied energy. The hot water was powered by a solar hot water unit, but due to a cockup in the plumbing somewhere it was feeding back into the cold water too, unbearable in summer so it got taken out again.

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Flooding is a different matter. I'll do some sketching.