Airbricks End inside extension!

[DanLeMac]

Hi everybody

I have an early 1900’s terrace house with an extension. When we bought the house we found out the extension never had planning permission blah blah blah the usual house buying stuff.

However, the extension was slammed to floor. We have to step down into the extension. This means the all airbricks at the rear of the property end inside the house, and right next to a heat and moisture creating kitchen.

We also have exposed floor boards in the main house. Rough estimate floor is raised about 20 cm.

Good airflow is becoming a problem and we’re starting to notice a dampy smell on certain days.

We can’t redirect any airbricks at the rear to go sideways. We can’t raise the floor height of the extension.

Any bright ideas around getting good airflow under the floor. Open to passive or active solutions.

Thank you for taking the time to read this.

Danny

P.s neighbour has underfloor heating and when he jacks that up the smell is worse.

 

[^woody^]

Those air bricks are normally venting the floor void to stop timber rot. That is not happening now, so there is a risk.

Also, the pressure difference is likely drawing the stale air from the floor void, including the neighbours through gaps in the party wall, into your room.

The airbricks should be ducted to the external air - normally that's under the new extension floor when it's built.

Big problem achieving that now. It depends on the layout and what level of cost and disruption you are open to.

 

[Notch7]

Hi everybody

I have an early 1900’s terrace house with an extension. When we bought the house we found out the extension never had planning permission blah blah blah the usual house buying stuff.

However, the extension was slammed to floor. We have to step down into the extension. This means the all airbricks at the rear of the property end inside the house, and right next to a heat and moisture creating kitchen.

We also have exposed floor boards in the main house. Rough estimate floor is raised about 20 cm.

Good airflow is becoming a problem and we’re starting to notice a dampy smell on certain days.

We can’t redirect any airbricks at the rear to go sideways. We can’t raise the floor height of the extension.

Any bright ideas around getting good airflow under the floor. Open to passive or active solutions.

Thank you for taking the time to read this.

Danny

P.s neighbour has underfloor heating and when he jacks that up the smell is worse.

you could gun up the floor and run 110mm pipe through....

usually where an extension with solid floor abuts a house with suspended floor and air bricks, the ventilation is extended to outside by using soil pipe through the new floor.

Ive certainly come across vents being terminated inside -Ive seen skirtings cut out for them -its not clever having a cold air vent inside though.


I dont know if its an acceptable solution, could you take on vent up vertically in pipework and vent through the extension roof? -maybe requiring an in line extractor fan

 

[freddiemercurystwin]

So do you still have air bricks remaining on one side of the floor void? If you can get a way to get air into the void (maybe from above the roof as mentioned above or something), there are various fans/extractors on the market that can be utilised to extract the air eg https://www.eltatrade.co.uk/product/mori-wmf/

 

[DanLeMac]

Hi
Thanks for the replies.
I’ve attached a picture to show where it ends inside the house.

I fully take on board the timber issue and while money is a factor here, it’s a home for life so there is wriggle room for the right solution.

As you can see from picture, it’s not ideal.

Many thanks for any advice

Danny

 

[DanLeMac]

 

[Ivor Windybottom]

Could you duct them sideways, either out of the side wall or roof, along the floor? Make a step over this in front of the door, at the same height as the higher floor. Would look like it was meant to be there if done right, and would probably help with stepping over the door threshold.

 

[freddiemercurystwin]

So the question remains unanswered, are there airbricks venting to the outside at the opposite end to these ie in the living room wall?

 

[Notch7]

Could you duct them sideways, either out of the side wall or roof, along the floor? Make a step over this in front of the door, at the same height as the higher floor. Would look like it was meant to be there if done right, and would probably help with stepping over the door threshold.

that would be my thinking

 

[DanLeMac]

So the question remains unanswered, are there airbricks venting to the outside at the opposite end to these ie in the living room wall?

Hi, yes. 3. Helpfully slammed to ground level with to French drain. We’re having these raised soon as I’m sure it won’t be helping.

 

[cdbe]

I have a crazy idea, only because I've run air supply pipes (110mm plastic) from front to back of my house for wood burner and gas tumble drier.

 

[DanLeMac]

Could you duct them sideways, either out of the side wall or roof, along the floor? Make a step over this in front of the door, at the same height as the higher floor. Would look like it was meant to be there if done right, and would probably help with stepping over the door threshold.

Maybe…. The kitchen entrance is also in extension. Not too keen on putting a step into the kitchen if I can help it.

But see what you’re saying. Ducting sideways is possible. Neighbour does have a fence panelling next to my extension though.

Roof of the extension is possible though.


Thanks

 

[freddiemercurystwin]

So if you can duct to the outside either in the side wall or the roof then you just need some extractors at the front to draw the air through, is the void under the original living and dining room floors restricted do you know?

 

[Ivor Windybottom]

There would be no point ducting from front to back, as you'd have all vents at the front. It relies on the wind to move air through, which only happens if they're in different places - usually front to back but front to side or roof would be reasonably OK.

 

[freddiemercurystwin]

That's why special extraction fans were linked to earlier in the thread, to mechanically draw the air through.