Block and Beam Air Bricks/Vents

[JamieB3009]

All,

About 18 months to 2 years ago i had an extension built onto my exisitng house. The existing house is block and beam with air bricks on all sides of the house. It didnt occcur to me at the time but now looking back at some old photos i can see that some of the air bricks have been blocked/covered as a result of the extension. Yes, i should have noticed this at the time and yes these should have been ducted out but I didnt and they werent. The arrangement of the air bricks in the external walls is as shown below (white boxes represent air brick locations). The three in red have been blocked.

Now i dont have any issues with damp or other ill effects so is this likely to be ok? I have no detail of the sleeper walls under the beams but will these be ventilated or solid? Would any issues have presented by now (2 years)? Any tests worth doing?

Thanks.

 

[noseall]

All,

About 18 months to 2 years ago i had an extension built onto my exisitng house. The existing house is block and beam with air bricks on all sides of the house. It didnt occcur to me at the time but now looking back at some old photos i can see that some of the air bricks have been blocked/covered as a result of the extension. Yes, i should have noticed this at the time and yes these should have been ducted out but I didnt and they werent. The arrangement of the air bricks in the external walls is as shown below (white boxes represent air brick locations). The three in red have been blocked.

Now i dont have any issues with damp or other ill effects so is this likely to be ok? I have no detail of the sleeper walls under the beams but will these be ventilated or solid? Would any issues have presented by now (2 years)? Any tests worth doing?

Thanks.

View attachment 371871

As long as the internal sleeper walls are honeycomb, I don't really see an issue.

 

[JamieB3009]

Thanks. I guess there isn't really any way of knowing that now is there given its all screeded and floored? The drawings I have for the house just state ventilation in accordance with buildings regs and nhbc guidance. The only other thing I can think to do is use a smoke generator or similar to put smoke in one side and see it come out the other??

 

[freddiemercurystwin]

I shouldn't worry, I'm not sure venting a void under a B/B floor really does much, there will (or should) be a continuous moisture barrier in the floor linked to cavity trays in the walls so how can any moisture issues under that barrier affect the inside anyway. Mr BCO needs a kick next time you see him though.

 

[JamieB3009]

Thanks. I know a full layer of dpm was laid throughout the entire area before insulation and screed so that should cover it. More worried if it is ringing wet down there that there might be corrosion of the steel in the concrete....

 

[freddiemercurystwin]

Any reinforcement in the beams should have adequate cover. Overthinking comes to mind .....