by 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.
[quote="scoffer"]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.[/quote]
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.