How long do I wait for backfill to settle?

Can anyone recommend a period of time to wait for backfill to settle before building on top of it? I'm sure the footings have to extend to solid/stable soil, but what else should I know before building? (one post suggested waiting two seasons)

A Friend of mine a few years back was also told to wait for Two Rainy Seasons to pass. Seems reasonable to me ??

Think I would ask a building contractor. Now there seems to be a lot around Udon these days compared to 4 or 5 years ago. Back then I was told one rainy season. And as you say:

I'm sure the footings have to extend to solid/stable soil

Before never seen big rollers around, now they are everywhere.

I have seen many big building projects with very little wait time. Look at the new CarryFour, Tesco, or NgeeSoon.

My understanding also is two years/rainy seasons, and to pile through the infill into the original underlying ground. The longer the better really.

have a look at this website

You will find all the info you need here

http://www.coolthaihouse.com/forum/viewforum.php?f=39

One really only need put the foundations into the "old" already compacted soil, build the first floor beams elevated on that, then backfill and compact. Since your floors would be on your beams, you'd be good to go. No need to wait any seasons that way.

Pouring a slab on top of a one or two season compacted fill and building up a house on it is like stepping on a sponge. That dirt is going to shift - especially if water gets under it the first rainy season after it is built. If you are building it on clay, build it to "float" or else when the clay swells, the house could tilt causing walls to crack. Examples can be seen all over...

Thanks to all that responded.
The location I refer to was a small pond not more than 2 meters deep. It was a clayish type of backfill raised approximately half a meter higher than the surrounding soil. It has been over a year now and only the side nearest to an existing pond shows any sign of movement. (cracks in the soil) Just going through the second rainy season now. The footprint of the house will cover 3/4 of the backfilled area leaving 15 meters to the adjacent pond. We will not build for another three years so I'm hoping for the best at this point.

So, you've got 2.5 m of backfill? Put your foundation deeper than that and you should be good to go. Alternatively, you could make a shallow footing provided it is broad enough. Something like 2 m x 2 m or so. How many you would require and where would depend on house design. Then, if you choose to pour directly on the soil surface (after laying your 6mil plastic so you do not get water seepage, of course), you would want to first make your rebar mesh so that it intrudes the beams at least 5 cm. You could drill into the beam, stick in rebar lengths, then connect with wire to your mesh. By doing this for each and every room, you effectively make the house "float" and self-bracing as the lateral friction surface is the entire first floor rather than just a wall, beam, or room.

But you've plenty of time to sort the details of the build. Cheers!

So, you've got 2.5 m of backfill? Put your foundation deeper than that and you should be good to go. Alternatively, you could make a shallow footing provided it is broad enough. Something like 2 m x 2 m or so. How many you would require and where would depend on house design. Then, if you choose to pour directly on the soil surface (after laying your 6mil plastic so you do not get water seepage, of course), you would want to first make your rebar mesh so that it intrudes the beams at least 5 cm. You could drill into the beam, stick in rebar lengths, then connect with wire to your mesh. By doing this for each and every room, you effectively make the house "float" and self-bracing as the lateral friction surface is the entire first floor rather than just a wall, beam, column, or room.

But you've plenty of time to sort the details of the build. Cheers!

One day is enough if you use the pounded in pilings method rather than the dugout foundation. The size and number of the pilings depends upon the design of the house. These posts support the weight of the house and are pounded until about .5 meter under grade.

This method provides a more stable foundation than any number of years waiting for fill to settle. It is more expensive, but not a lot more.










After the pilings are pounded in a steel reinforced base several times larger that the diameter of the post is poured on top of each piling. These are used to anchor the upright posts and horizontal beams. After which the construction is pretty much the same as a dugout foundation.

Point taken re the above and the fact that your house will be sitting on the piles, piled through to the original underlying ground. But be careful your drive, garden and paths won't be, so you'll likely suffer from subsiding garden, paths and possibly internal floors. So you may end up with cracked drives, tiled paths and floors. That's why I would prefer the 2 year wait.

Certainly, when making a major expense one should do what makes one comfortable with the project.

After 4 years I've had no problems with settling other than the wall around the property which was built by digging down into the native dirt for the foundations posts. The workers failed to properly back fill and tamp the dirt. Consequently, I've had to fill around most of the posts for the past years. So far this rainy season it looks like things may have finally been filled as there's been no settling so far.

My garden, walkways, undergroung drainage and irrigation systems, and driveway have not had settling problems. The property drains from the back to the front drive as I asked the builder to do.

Most of the homes I've seen built here have the horizontal beams built on grade so they raise the floor of the house 3 or 5 steps above the surrounding property. After pouring the horizontal beams they hand fill the space for each room with dirt. This dirt is not mechanical tamped, so undoubtedly almost all homes have some settling under their floors, but as long as there is not water penetration that settling should be minimal. The floors have to be strong enough to carry their own weight as well as furnishings, etc. The horizontal beams carry the weight of the walls and some of the weight of the floors. The upright posts carry the weight of the roof and ceiling which is suspended from the roof in many homes.

Can anyone take a guess at the installation cost per pile? I've been told that is probably the method I will need to use. This is in the Chachoengsao area.

KHONDAHM wrote:One really only need put the foundations into the "old" already compacted soil, build the first floor beams elevated on that, then backfill and compact. Since your floors would be on your beams, you'd be good to go. No need to wait any seasons that way.

Pouring a slab on top of a one or two season compacted fill and building up a house on it is like stepping on a sponge. That dirt is going to shift - especially if water gets under it the first rainy season after it is built. If you are building it on clay, build it to "float" or else when the clay swells, the house could tilt causing walls to crack. Examples can be seen all over...

Since I'm in the game a well that was my thought as well. Rice paddies have a lot of compaction of the years.

Mine may just turn into a hobby farm only talking 200 Talang Wah.

Everything rest on if we can get the build financed I doubt it 64 years old, wife no independent income, except the stock market.

We already have a home to live in so it s doesn't really matter to me.

By the way I have seen a different method then the pile driver being shown. The dig down to the original soil. Make a Pad on the ground from cement to spread the weight, the construct the beam on that. That won't stop other locations from settling, like driveways and fence foundations.

I conveinced that no matter what you do you will experience hair line cracks in your walls. There is a special paint for that.

I'm probably going to have a small vineyard, I doubt I will get financed

Thanks Bumper! Not sure what 64 years young has to do with it but I'm in the same situation. I'm no doubt at the will of previous dreams of prosperity and the termoil of change. I was just trying to get a grip on how much to save. There are so many pieces to this plan I would like to discuss but not sure this is exactly the right forum. Hope so. Anyway, I predict small imperfections along the way. Don’t know of any house that hasn’t experienced some issues.
Hey, wish you the best on your vineyard. You never know, maybe a new variety of grape or an excellent year for wine?
Alan