Hi everybody...
I am in a bit of a pickle, i am building an 8m x 3m extension on clay ground and have reached sponge! The kids love it but im pulling my hair out to find an answer.
I have dug through 1ft of topsoil, 1ft of rubble (newbuild house!!!) and about a ft of clay. The problem i have is this:
My architect placed a raft foundation on the building regs which got approved, his depth was approx. 750 below ground level and footing width is 700. I have dug down to this (am cream crackered!) and have mostly clay. 50 percent of the foundation base is pretty solid but the other 50% is spongy in areas.Im a little concerned that if i continue to put in steels and concrete the thing i will have severe problems later.
My current footing level that i dug to is exactly the same as the existing house foundations.
The internal foundation base is fine (architect put in an internal wall foundation with steelwork even though it carries no load bearing walls), Theres also a 50mm flexcell going in the internal foundation wall
The eternal front base is solid
The rear is like a sponge cake
the outer length of the house is spongy in certain areas.
We have greenbelt land to the side of us (within 10metres) which gets very waterlogged (im told theres a brook running through it, never found it though!!!) and no major trees near the proposed extension (as i ripped all the conifers out that posed any threats as instructed by the BCO)
Can someone tell me where i go from here?.. do i add a lean mix in the base to help combat the sponge?
Any advice is welcome. am pretty desperate!
I am in a bit of a pickle, i am building an 8m x 3m extension on clay ground and have reached sponge! The kids love it but im pulling my hair out to find an answer.
I have dug through 1ft of topsoil, 1ft of rubble (newbuild house!!!) and about a ft of clay. The problem i have is this:
My architect placed a raft foundation on the building regs which got approved, his depth was approx. 750 below ground level and footing width is 700. I have dug down to this (am cream crackered!) and have mostly clay. 50 percent of the foundation base is pretty solid but the other 50% is spongy in areas.Im a little concerned that if i continue to put in steels and concrete the thing i will have severe problems later.
My current footing level that i dug to is exactly the same as the existing house foundations.
The internal foundation base is fine (architect put in an internal wall foundation with steelwork even though it carries no load bearing walls), Theres also a 50mm flexcell going in the internal foundation wall
The eternal front base is solid
The rear is like a sponge cake
the outer length of the house is spongy in certain areas.
We have greenbelt land to the side of us (within 10metres) which gets very waterlogged (im told theres a brook running through it, never found it though!!!) and no major trees near the proposed extension (as i ripped all the conifers out that posed any threats as instructed by the BCO)
Can someone tell me where i go from here?.. do i add a lean mix in the base to help combat the sponge?
Any advice is welcome. am pretty desperate!