House foundations

Elsie161211

Hi, I am about to start building next year ( hopefully ). The site is quite wet with a lot of water sitting on top not going anywhere although tractors were driving on it in the summer and it was grand. We cleaned out the existing drains which had been blocked for years. I wanted to have an idea whether or not we will require a raft foundation or will we get away with a standard strip foundation. I dug a hole in the ground and after about a foot I hit this grey soil ( someone said the name is lack ), I dug down a further 2ft and it still this grey lack although it gets harder. Will we be able to put foundations on top of this grey soil or will we have to keep digging till we get past it.

Also the person who cleaned the drains said the reason the water was sitting on top of the ground was cause the water can not penetrate down past the grey soil so we will have to down a good bit of drainage

Any help would be grateful!!

Ollie

jack of all

To be quite honest you need professional advice and you can only get that from a qualified engineer who can visit the site and see the ground conditions and make a proper appraisal. If the ground conditions dictate a raft foundation this would need to be designed by an engineer in any case.

Elsie161211

Thanks Jack of all,

lostboy75

That's a term my grandfather used, so I also use, don't really know what the proper term is, but it's a dense really poor draining soil. As mentioned you need profeshional advice. This could also effect your perculation areas

gutteruu

Sounds like 'Marl'. Definitely an engineer's job.

pandg

you may not need a raft foundation , may be ok if you dig down 600 or 700 mm more than normal and put in a lean mix and then pour foundation on top of that incorporating steel . even with an engineer on board you wont know for sure till you start to clear site and dig

mickdw

I am an Engineer and i know the type of ground you are referring to.
While there are variations of this type of soil in different parts the county, my general conmments would be as follows:

It wouldn't form a suitable base for a strip foundation. You can of course dig all the way through it to a more solid gravel layer. Your site will dictate as to whether this is an option. It may be the case that you have a very deep layer of this. In that case, an alternative foundation type should be considered.
One problem with this type of soil is that it can be reasonably solid when undisturbed but really swamp ground if disturbed or if it gets wet when exposed.
You need an Engineer to inspect and certify anyway so they will come up with the most cost effective solution.

Elsie161211

Thanks for all the comments, i guess I will just have to wait for the spring to find out for sure once I start clearing the site and have an engineer decide

braddun

ask people that have built nearby

get a local site clearence expert/ diggerman out on site and get his opinion

650gs

You do know the reg's regarding self build and having a reg contractor

smartgardener

reg contractor in canada its a law

braddun

can you build on stilts


http://www.treehugger.com/green-architecture/passive-house-built-stilts-2.html

650gs

smartgardener wrote: »

reg contractor in canada its a law

What has Canada got to do with it ?????