underfloor/underhouse ventilation advice

[delderek]

Can anyone advise on what kind of airflow I should expect under my property. I've not had cause to stick my head under the floorboards on many occasions however, whenever I have I have felt a decent through breeze under there. I've just had some building work near completion and the builders blocked 4 out of the 5 original Airbricks to the rest of my property when constructing my extension despite the approved plans specifically stating that they should not be blocked.

Cutting a very long story short they now say that the air bricks (and therefore subsequent under house airflow) has been reinstated.

Now, I opened up a trap door which is situated pretty much in the middle of my house and I could feel little or no air. To test this I replaced all but one of the 5 cut pieces of floorboard which forms the trapdoor and held a long piece of thin tinfoil down it.

There was no movement whatsoever. I now fear that if I don't stamp my feet with the builders and the planning department over this now I c pulled regret it in years to come.

Should there be an evident draught, particularly on windy days?

The builder also floored my extension but left a large puddle about 1 inch deep at one side (due to short busts of poor weather during the build) in my extension solum? I would have expected him to dry it out first but he just shrugs that I'll dry out. In my opinion there is much less chance of this due to what I see as poor air circulation underneath.

It has taken the gloss off of what has been an otherwise good build.

Any advice on what I could or should do would be appreciated.

Thanks

 

[simonjay]

Can anyone advise on what kind of airflow I should expect under my property. I've not had cause to stick my head under the floorboards on many occasions however, whenever I have I have felt a decent through breeze under there. I've just had some building work near completion and the builders blocked 4 out of the 5 original Airbricks to the rest of my property when constructing my extension despite the approved plans specifically stating that they should not be blocked.

Cutting a very long story short they now say that the air bricks (and therefore subsequent under house airflow) has been reinstated.

Now, I opened up a trap door which is situated pretty much in the middle of my house and I could feel little or no air. To test this I replaced all but one of the 5 cut pieces of floorboard which forms the trapdoor and held a long piece of thin tinfoil down it.

There was no movement whatsoever. I now fear that if I don't stamp my feet with the builders and the planning department over this now I c pulled regret it in years to come.

Should there be an evident draught, particularly on windy days?

The builder also floored my extension but left a large puddle about 1 inch deep at one side (due to short busts of poor weather during the build) in my extension solum? I would have expected him to dry it out first but he just shrugs that I'll dry out. In my opinion there is much less chance of this due to what I see as poor air circulation underneath.

It has taken the gloss off of what has been an otherwise good build.

Any advice on what I could or should do would be appreciated.

Thanks

How did they reinstate the air bricks ?
You may have to check what they did.
If the new extension has an underfloor void that should have air bricks itself and be open to the original underfloor.
If the extension is solid floored they would need to duct the old floor through to the outside somehow.