I am building on a hobby farm I own in a rural area. This is in a flood area and so the finished floor level would have to be 1.2-1.3m above the natural ground level at the site. While I haven't had soil tests done yet, the site is on fairly heavy clay that cracks when dry, so I'd imagine it is at the more reactive end of the scale.
Before I go to a designer, I would like to be a bit more informed about the viability of bringing in a lot of fill and building a slab vs. building to this height on stumps and if anyone has experience with a similar situation. I like the idea of a slab for the thermal properties, however based on some preliminary comps I would need to bring in over 1000m3 of fill.
Some more specific questions I have are as follows;
- For the soil used for the fill, are there any requirements as to the type of soil used? Or can most soils be compacted to a good enough standard? I am looking to have a dam dug as well which could be used but this would be red clay.
- Stumps - does the required height above ground level increase the cost much vs say a 300mm floor height? Obviously more material but are there any other considerations to think about?
- Longevity and/or susceptibility to movement - every man and his dog seems to have an opinion (often conflicting) on this with slab vs. stumps - if anyone has anything to add based on my specific situation that would be appreciated
- If using a fill pad - what sort of batter grade/slope is 'comfortable', i.e. easy to walk up, gentle enough for a ride on mower. 1 in 10? 1 in 20?
Any advice on the above or experiences anyone can share would be awesome.
Cheers
Gus