We live in a 1931 semi with suspended timber floors in the living room/dining room. We have lived here for 11 years with no previous problems of this kind.
Last month we detected a foul smell coming from under the floorboards in these rooms (it smelt like sewage). There are no pipes under the floor except for the central heating radiator pipes but the central heating has not been a problem and we have lost no pressure.
We removed some floorboards and found a sort of drainage gully moulded into the concrete foundations of the house. We were previously unaware of this gully and don't know it's exact purpose or where it is draining to/from.
We hired a water vac and removed the water (about 30 litres removed). This has left a white slimy residue. The smell is improved (you can't smell it when the ground outside is frozen) but when the outside temperature rises the smell returns. It's not terrible but bad enough to warrant spraying air freshner.
We are unsure what to do next. It has been ten days since we removed the water. Do we wait a while longer to see whether the smell subsides? This doesn't solve the mystery of why the water was in the gully or where it came from.
The possible explanations include two very wet summers (we are on a clay soil and our back garden becomes waterlogged very easily) or a new patio which was fitted last march. This is the second patio we have fitted in eleven years. The previous one had a gap aorund the house filled with slate chippings. The new patio abutts the house but remains below the level of the damp prooof course (though about an inch below the air brick). The patio has been laid on a slope to direct water away from the house.
Any advice gratefully received. What sort of professional would we approach to investigate formally?
Thanks
Last month we detected a foul smell coming from under the floorboards in these rooms (it smelt like sewage). There are no pipes under the floor except for the central heating radiator pipes but the central heating has not been a problem and we have lost no pressure.
We removed some floorboards and found a sort of drainage gully moulded into the concrete foundations of the house. We were previously unaware of this gully and don't know it's exact purpose or where it is draining to/from.
We hired a water vac and removed the water (about 30 litres removed). This has left a white slimy residue. The smell is improved (you can't smell it when the ground outside is frozen) but when the outside temperature rises the smell returns. It's not terrible but bad enough to warrant spraying air freshner.
We are unsure what to do next. It has been ten days since we removed the water. Do we wait a while longer to see whether the smell subsides? This doesn't solve the mystery of why the water was in the gully or where it came from.
The possible explanations include two very wet summers (we are on a clay soil and our back garden becomes waterlogged very easily) or a new patio which was fitted last march. This is the second patio we have fitted in eleven years. The previous one had a gap aorund the house filled with slate chippings. The new patio abutts the house but remains below the level of the damp prooof course (though about an inch below the air brick). The patio has been laid on a slope to direct water away from the house.
Any advice gratefully received. What sort of professional would we approach to investigate formally?
Thanks