Airbricks in Lean-To

[Rob_Quads]

In my lean too there are 2 airbricks on the side of the original house. It appears that some little friends are crawling out of them and into the conservatory.
Would it be dangerous to place a temporary cover over the air-bricks?

 

[Mr Winston]

am i right in assuming these airbricks are ventilating the floor void?

if so they should be ventilating to fresh air rather than the conservatory enclosure so i cant imagine that blocking them temporarily ( a few weeks?) would be that much worse.

ultimately i would put supplementry air bricks in either side of the conservatory if possible and block off the ones in the conservatory