Patio Level and Air Bricks

aj9648

Hi

I had a new extension a few years ago and now getting onto doing the garden.  When I have looked at the patio level - it seems that where I will be installing an Aco Drain, it will partially cover the airbrick that has some ducting into the old part of the house.  

I have 2 airbricks at the front of the house and 2 on the side.

What options do I have in this situation? (see pic)

FreeBear

Ideally, the level of the patio should be ~150mm below the DPC - This is to reduce the risk of rain splashing up off the hard surface and soaking the wall.

With 150mm clearance, that would leave the air brick fully exposed.

aj9648

FreeBear said:

Ideally, the level of the patio should be ~150mm below the DPC - This is to reduce the risk of rain splashing up off the hard surface and soaking the wall.

With 150mm clearance, that would leave the air brick fully exposed.

The dpc is there. On the photo on the render bit to the right it’s just below that. It will be 150mm to the level of the final patio finish. 

I just don’t understand the air brick location and why it’s there !! 

Eldi_Dos

If there is a duct behind airbrick running  through extension to original airbrick of house they may have put slope on duct so any condensation forming in the duct ran away from house, could be one possible explanation.

MikeJXE

The older part of the house has probably got suspended floors and the airbricks are for ventilation, a through flow of air  front to back 

aj9648

MikeJXE said:

The older part of the house has probably got suspended floors and the airbricks are for ventilation, a through flow of air  front to back 

Yes it is suspended flooring.

MikeJXE

aj9648 said:

MikeJXE said:

The older part of the house has probably got suspended floors and the airbricks are for ventilation, a through flow of air  front to back 

Yes it is suspended flooring.

Then don't cover the airbricks 

EssexExile

Is there going to be a step at the patio door? Assuming the patio surface will be below the airbrick you could leave a space under the step for air to access the airbrick, effectively continuing the ducting.

grumbler

With such a high step it hardly makes sense to install Aco Drain unless the the patio is built incorrectly with a slope towards the house. Surely, the intention was to make the levels about the same, hence the Aco Drain. If so, it's yet another bodge job of notorious UK cowboy builders. The air brick(s) should have been placed on the side(s) of the patio door and higher up, with  telescopic vents.

The channel(s) under the floor should have been directed accordingly.

aj9648

EssexExile said:

Is there going to be a step at the patio door? Assuming the patio surface will be below the airbrick you could leave a space under the step for air to access the airbrick, effectively continuing the ducting.

No step will be placed on patio door