Can I block this air vent please ?

[Bdazzling]

Hi, I am new to this forum and just looking for a bit of help and advice please.

I live in a bungalow which is gas central heated and double glazed. My question refers to an air vent in my daughters bedroom, this is a big room, approx 25' x 14' .

The air vent in question is on the chimney breast, we had the chimney removed several years ago so in effect this vent is just going up into the loft space and no where else. It has a slide cover on which we generally close as I like to have windows open but I wondered if it was safe to block this vent up completely please and if so how ?

I have read through other posts but most vents seem to be on an outside wall and this one isn't

Any advice would be gratefully appreciated

Thanks

 

[pinenot]

You say you had the chimney removed, by this do you mean the chimney on the roof was removed completely and roof tiles made good? Presumably the internal chimney breast is intact, hence vented. If you decide to block the vent under this scenario, then you run the risk of allowing condensation to build up and dampness to occur.
Now I wonder if the stack itself was capped inside the loft? This would have the effect of reducing air flow from the cold loft terminating much of what appears to be your concern...pinenot