Hi,
I have a suspended floor throughout most of downstairs in 1930s semi. Most of it has floor insulation, screed, wet underfloor heating and engineered wood floor - except the cupboard under the stairs where a damp smell is rising. We have a water meter which shows it is very unlikely to be a leak. Neighbours have issues with damp from underfloor too. We have four air vents at the front and two at the back. In picture striped lines show concrete instead of suspended. There was one in the garage/near the stairs but covered up as garage built years ago.
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When I had UFH put in, there was flooding present in the sub floor void at the rear of the house. a drain had previously been constructed there to deal with this - probably due to a combo of clay soil and house being on a hill. We reinstated the drain to manage the water pooling on that side of the house but clearly it's still wet somewhere under there (two years later). I've lifted the floorboards in the cupboard under the stairs and the ground is damp.
Our neighbours all say their downstairs rooms sometimes smell musty after rain but I want to avoid this as much as possible because some joists were rotting (since replaced) and the smell is rank.
I've shared some photos in the hope someone can offer some advice on increasing ventilation/reducing wet ingress.
Possibilities/ideas so far:
1. Have Thames Water survey the surface water gulley at the front of the house. There is a surface water drain running from all houses across the front of the house. This is going to be earthenware and old so might be leaking.
2. Remove the bush in front of the air vent. Wife not keen on this one.
3. Dig a channel around the front of the house and fill with shingle.
4. Dig out the concrete covered front garden and lower the ground level here.
5. Add another airbrick at the front (not possible at the back) - builder attempted this but did it really badly and it just went straight to the screed?? Not sure how this can be done with screed/UFH? Could try to cut through the screed from the front of the airbrick?
6. Add a vent to the understairs cupboard to create airflow through here? Will smell for a while but hopefully will help to dry out the subfloor and can always close it if too bad?
7. Repair cracked render on plinth? Is this pointless?
8. NUCLEAR OPTION: seal the understairs floor/covered with lino and try to forget about it.
9. Reinstate an airbrick to the side but just have it go into garage.
Would like to know what think would be most effective to increase ventilation.
Thank you in advance
I have a suspended floor throughout most of downstairs in 1930s semi. Most of it has floor insulation, screed, wet underfloor heating and engineered wood floor - except the cupboard under the stairs where a damp smell is rising. We have a water meter which shows it is very unlikely to be a leak. Neighbours have issues with damp from underfloor too. We have four air vents at the front and two at the back. In picture striped lines show concrete instead of suspended. There was one in the garage/near the stairs but covered up as garage built years ago.
When I had UFH put in, there was flooding present in the sub floor void at the rear of the house. a drain had previously been constructed there to deal with this - probably due to a combo of clay soil and house being on a hill. We reinstated the drain to manage the water pooling on that side of the house but clearly it's still wet somewhere under there (two years later). I've lifted the floorboards in the cupboard under the stairs and the ground is damp.
Our neighbours all say their downstairs rooms sometimes smell musty after rain but I want to avoid this as much as possible because some joists were rotting (since replaced) and the smell is rank.
I've shared some photos in the hope someone can offer some advice on increasing ventilation/reducing wet ingress.
Possibilities/ideas so far:
1. Have Thames Water survey the surface water gulley at the front of the house. There is a surface water drain running from all houses across the front of the house. This is going to be earthenware and old so might be leaking.
2. Remove the bush in front of the air vent. Wife not keen on this one.
3. Dig a channel around the front of the house and fill with shingle.
4. Dig out the concrete covered front garden and lower the ground level here.
5. Add another airbrick at the front (not possible at the back) - builder attempted this but did it really badly and it just went straight to the screed?? Not sure how this can be done with screed/UFH? Could try to cut through the screed from the front of the airbrick?
6. Add a vent to the understairs cupboard to create airflow through here? Will smell for a while but hopefully will help to dry out the subfloor and can always close it if too bad?
7. Repair cracked render on plinth? Is this pointless?
8. NUCLEAR OPTION: seal the understairs floor/covered with lino and try to forget about it.
9. Reinstate an airbrick to the side but just have it go into garage.
Would like to know what think would be most effective to increase ventilation.
Thank you in advance
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