Building a house - Sub Structure / Foundations

Here is the place to post any simple or complex questions you may have about any aspect of life in Cambodia and beyond without fear of being told 'That question has been asked 100 times before.'

Re: Building a house - Sub Structure / Foundations

Postby starkmonster » Fri Mar 02, 2018 1:15 pm

Joking aside, if you want to do some more reading on this the term you are looking for is hydrostatic uplift. There are lots of solutions, but they won't be cheap and will be way above the pay grade of uncle Heng the village builder.
User avatar
starkmonster
MerkinMaker
 
Posts: 3077
Joined: Wed Mar 21, 2012 11:04 am

Re: Building a house - Sub Structure / Foundations

Postby kinard » Fri Mar 02, 2018 2:14 pm

starkmonster wrote:Joking aside, if you want to do some more reading on this the term you are looking for is hydrostatic uplift.

Pretty sure this applies to clay only, and usually when tank is empty or near to it.
There's a reason something as heavy as an aircraft carrier can float,

Buoyancy?
'Understanding is a well-spring of life to him who has it, but the correction of fools is folly' -Proverbs 16:22
User avatar
kinard
I can not turn my computer off ...
 
Posts: 5349
Joined: Tue Jun 28, 2011 9:16 am

Re: Building a house - Sub Structure / Foundations

Postby crazyjohn » Fri Mar 02, 2018 3:48 pm

Just been talking with my Khmer engineer mate. He works for the borey company building on the Northbridge land. They are about to build several 20 level towers on the land that was the pretty lake in the Northbridge grounds. They will excavate several metres deep and then drive in piles, no problem at all apparently. I will give it a good coat of looking at next month.
crazyjohn
I've got internet at work
 
Posts: 280
Joined: Wed Apr 05, 2017 10:32 am

Re: Building a house - Sub Structure / Foundations

Postby scoffer » Fri Mar 02, 2018 4:29 pm

Thanks for the replies, they make the brain churn over and then one looks at solutions / options.

The land I'm looking at is about 4 ft lower than the road but on par with all other land in the area,
Flooding is not a real issue, but there will be a substantial amount of ground water around for a day or two if a torrent of rain happens,
But it all slopes to the rear, so will not gather around the proposed house site.

The land is about 22mtrs wide and 80mtrs deep
Rather than try to infill the the entire plot, I was considering - stepping it down into 3 levels

Area 1)
The land closest to the road and where I want to build the house on,
Dig out a basement, lay foundations, support walls and build the house on these foundations .
Make use of the sub floor area for a temperature controlled environment for sleeping or other projects ( Mushrooms, hydroponics - stuff like that )

Area 2)
The land immediately behind and to the side of the house ( starting approx 25 mtrs from the road and ending about 65 mtrs towards the end of the plot)
In fill it to be about 2ft lower than level 1), Make use of this area to amuse myself with whatever I want to grow/produce in this area.

Area 3)
A sink hole to collect water being drained from level 1 + 2 and to be use to provide water as required
I refuse to go out with nothing more than a whimper followed by a small farting sound and a shit stain on my bed sheets..
Just thought I'd share that with you.
User avatar
scoffer
Tech Ninja / Kangaroo Baiter
 
Posts: 7878
Joined: Sun Mar 28, 2004 1:01 pm

Re: Building a house - Sub Structure / Foundations

Postby Fred Edwards » Fri Mar 02, 2018 6:01 pm

Sump
Hear and hear, but do not understand; see and see, but do not perceive.
For they do not know what they hear, see, say, or do, and yet they do not concede that they are blind and deaf.
User avatar
Fred Edwards
I Have Not Been Outside in a Week
 
Posts: 982
Joined: Tue Feb 02, 2016 10:42 am

Re: Building a house - Sub Structure / Foundations

Postby vladimir » Fri Mar 02, 2018 6:53 pm

House at street level, on stilts

Veggies farm at level 2

Fish-farm at level 3
Unless you believe that the future can be better, it's unlikely you will step up and take responsibility for making it so. If you assume that there's no hope, you guarantee that there will be no hope. -Noam Chomsky
User avatar
vladimir
Feminist Watch List
 
Posts: 33192
Joined: Thu Sep 23, 2004 7:43 am
Location: The Kremlin

Re: Building a house - Sub Structure / Foundations

Postby v12 » Sun Mar 04, 2018 4:53 am

scoffer wrote:I'm investigation the option of building a house with a basement.
The land I'm looking at needs a lot of in fill to bring it up to street level.

So I'm thinking I might dig down another 6-8 ft and put in a basement and build the house on top of this sub structure.

Suggestions on sourcing a competent engineer / builder to discuss this with would be appreciated.

Having 2 concrete floors on top of a basement is usually enough to avoid the whole structure including basement starting to float. Your concrete volume should be around 1/8 of the volume of the basement, then you get to the safe side. If your ground/first/second floor is made from low-weight baked stones, you may get into troubles. Use concrete throughout.

The moment ground water level will be above the basement floor you need serious measures to keep the water out. I would say, ground water level should even be some 1-2 feet below the basement floor, because of capillary creep, resulting in water collection on your basement floor.

Not to speak about water that simply "flows" into the basement through normal openings (ventilation, access, etc). Let alone the expected cracks in the basement wall, maybe even before finishing the construction.

A lot of Dutch people have their houses below sea level, though they solve the water problem, using external waterworks (channels, dikes, fingers in dikes, etc). And even then, every 10-20 years, some panics arises and whole towns/areas get evacuated because of imminent flooding. Despite that, Dutch engineers are invited around the world for major waterworks.....

Advise: Think in building on stilts. When having a car, prepare for a construction to have the car lifted from the ground floor, just in case a once in 5-10 years major flooding (Thailand not so long ago, remember ?) shows up.

When you persist on a basement, consider a house on a mound, where your basement is again at ground floor (street) level.
v12
Wibble Wibble ?!?
 
Posts: 1814
Joined: Sun Jun 11, 2006 8:51 pm

Re: Building a house - Sub Structure / Foundations

Postby Visser » Sun Mar 04, 2018 8:50 am

Ground water coming in is no problem as long as you waterproof the basement (or just use good quality concrete to begin with)
We have indoor parking places in Holland that go down to -22 meter with groundwater levels at -1M.

There hasn't been panic over here since the 50's when the south-west flooded after a big storm. The reason some area's get evacuated nowadays is when extremely high peak levels in the rivers are expected and they use low laying area's near the river as a buffer to take the edge of.
None but ourselves can free our mind.
Visser
I Have Not Been Outside in a Week
 
Posts: 934
Joined: Fri Feb 11, 2011 1:45 am

Re: Building a house - Sub Structure / Foundations

Postby v12 » Mon Mar 05, 2018 5:24 pm

Visser wrote:Ground water coming in is no problem as long as you waterproof the basement (or just use good quality concrete to begin with)
We have indoor parking places in Holland that go down to -22 meter with groundwater levels at -1M.

Sure, though it comes with some major technical capabilities (short term as well as long term) not present in Cambodia. Even in Thailand, car parkings are the first couple of stories of sky scrapers, they don't go down. And the subway closes down, when flooding threatens.

Visser wrote:There hasn't been panic over here since the 50's when the south-west flooded after a big storm. The reason some area's get evacuated nowadays is when extremely high peak levels in the rivers are expected and they use low laying area's near the river as a buffer to take the edge of.

You may have been missing the news on this. No personal casualties, though major financial damages due to several events.
v12
Wibble Wibble ?!?
 
Posts: 1814
Joined: Sun Jun 11, 2006 8:51 pm

Previous

Return to Questions and Answers




Who is online

Users browsing this forum: joelightcloud, logos, patcan and 43 guests