I am in the process of building a home. The concrete block walls for my porch and garage are 5 courses high. (I’m in a flood plane) The builder is planning to backfill inside the walls with dirt and then pour the concrete pad on top. I am worried that the dirt will settle and my floors will crack and warp. Is it common practice to backfill large areas like that with dirt? I realize that to fill that area with stone will be very expensive but I don’t want headaches down the road. Any advice?
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Around here you can only fill with sand or granular fill, NO dirt allowed even in a crawlspace....................Rik............
little confuse here. Inside the block itself with concrete only. inside the wall bewteen two block walls with dirt, we do it everyday , every job, just compact the dirt real good. most of the weight of the slab is on the wall itself which are on the footers.
I've had to dig it out twice , never again, the only fill any inspector will allow under a slab here (Victoria B.C.) is sand or gravel,no oil , clay , dirt etc. and only ontop of undisturbed non organic subsoil/rock. You can backfill the outside of your house with whatever you want as long as it is not under the drive way.
Doesn,t matter if it's engineered as a suspended slab or not................don't know if the building code specifies it or not here but it's the inspector that counts ..........Rik....
as a private soil/ concrete inspector, your bldg inspector is wacko.
Edited 7/1/2004 9:54 pm ET by BROWNBAGG
I've been building residential and commercial in 5 different municipal jurisdictions in B.C. for over 20 years and everyone is the same ..................I guess it must be a local concern ..........visited a few jobsites in Ont. and never saw any dirt fill there either ........lately about 2 out of 3 foundations the inspector wants to see a geotechs report before we can pour ..........here a few municipalities have been sued over the 'leaky condo'crisis in the last ten years also .................Rik.......
Following Brownbagg's post, this is done all the time.
A proper job consists of suitable soils (no organics, no expansive clay) processed to optimal moisture content and compacted in 8" lifts to 95% - 98% of maximum density. Get the slab on it before the dirt dries out or freezes and you should be fine.
DRC