Air bricks - How many, and is it actually doing anything?

[Tom079555]

I moved into a victorian house and the previous owner had covered the air brick in the living room (under suspended floor), so the room would get a bit smelly.

I have since unblocked this so the room is now less smelly, but not completely fresh.

I have added an additional air brick but neither one seems to be particularly 'breezy'. They are free and unclogged but seem almost pointless.

The floor is suspended by around 300mm and the floorspace is around 12-15m².

I now have 2 air bricks for this space. Should I be able to feel much draft on the inside if my hand is behind them. They seem a bit pointless.

Can this tiny air flow be doing anything at all?

 

[Mr Chibs]

Are the other rooms also ventilated?

I added more vents in my house, and made sure the breeze can blow in from any side of the house and exit from any side too.

Fly in the ointment is when there is a concrete floor as you won't be able to continue the ventilation through it.

 

[Harry Bloomfield]

The floor is suspended by around 300mm and the floorspace is around 12-15m².

I now have 2 air bricks for this space. Should I be able to feel much draft on the inside if my hand is behind them. They seem a bit pointless.

Such a space really needs a through flow, in at one side, out the opposite side - the wind, does the work.

 

[Tom079555]

Thanks for the responses.

It's a terrace house, so no option for side ventilation.

The front room and hall have a suspended timber floor, the back of the house has a concrete base.

The space now has 2 air bricks about 1 meter apart from each other - not much I know, but the space is small.

I was just concerned that it didn't seem to have much breeze. Maybe it just needs a windy day ‍

 

[Mottie]

Are the other rooms also ventilated?

I added more vents in my house, and made sure the breeze can blow in from any side of the house and exit from any side too.

Fly in the ointment is when there is a concrete floor as you won't be able to continue the ventilation through it.

We have them front rear and side too. When we added a front extension with a solid floor, we put 4 air bricks in the wall with double 3” pipes going from behind each vent, through the conc base and into the suspended floor area.

 

[Harry Bloomfield]

The front room and hall have a suspended timber floor, the back of the house has a concrete base.

Is that concrete, as it was built? Are you sure, there isn't a pipe or similar, to allow through flow the concrete? Air will only flow well, if there are vents on two opposing faces of a building. Two vents, on the same side, will achieve nothing much.

An alternative way is to have two vents on one side, but one of the vents include a low power electric fan, to encourage the air to flow.