Ventilation of internal room through hallway?

[JennyC]

I'm planning on doing a rear extension and as such, I will be left with what was the old kitchen (around 3m x 3m) as an inner room with no openable windows. The plan is to split it into a 1m wide corridor that will allow access between the current entrance hallway and the new extension, leaving a 2 x 3m area that I'd like to use as a small study.

As the study area will have an entrance directly from the hallway then I think I am ok with regards to Part B, but Part F doesn't seem to have much guidance for my situation. Paragraphs 5.14 - 5.16 talk of ventilation of habitable rooms through other habitable rooms/conservatories. But I am going to be ventilating what is presumably classed as a habitable room (study) through a hallway.

The hallway contains the front door which I hope will provide sufficient purge ventialtion (or does it have to be a window?) and I am replacing the front door so will make sure to include trickle vents. Do you think I can follow 5.14-5.16 even though my internal room will be ventilated through a hallway and not another habitable room? And when it talks of a permanent opening between the two rooms, can this opening be fitted with an internal door to make it a separate room or does it have to literally remain permanently open? I don't know many people who have a permanent opening through to their conservatory with no door so assume I am being too literal.

 

[tony1851]

Why not just leave the door off, regard the space as just a part of the hall, and fix a door as and when?

 

[^woody^]

If you are doing things properly, then you can't have ventilation via any other room or hallway. Ventilation is to external air

 

[tony1851]

If you are doing things properlyr

 

[JennyC]

Why not just leave the door off, regard the space as just a part of the hall, and fix a door as and when?

D'oh, yes that seems a fairly obvious way to get it signed off. Although I don't actually intend to be in there with the door shut often, I'm also curious as to how stuffy it might get if I'm trying to work on a computer for a couple of hours. So I may end up not having a door in the end anyway but will have to see what it's like once the wall is in place.

If you are doing things properly, then you can't have ventilation via any other room or hallway. Ventilation is to external air

Although the "fresh" air will be coming from the hallway and not from outside, in this particular situation I think it will work for my set up, at least I hope it will.

I assume from the fact that the Building Regs say you can have ventilation via another room that you don't consider that to be doing things properly - would you recommend fitting an extractor fan in this situation? Obviously I've looked at trying to postion things in such a manner that I can have an external window but it's not possible and I'm just looking to find a decent use for the inevitable room-locked space that will be left from putting an extension on the house.

 

[SimonH2]

Common sense would suggest that even if you can get away without anything, you should make provision for a duct so you can have an extractor fan if you find you need it.
EDIT: Ie, make provision so that if you find you need it, you don't have to start ripping up your decor to add it. The ducts can be quite compact, and subject to directions etc, can sometimes be run between the joists while you have access (before boarding over).

Small enclosed spaces can quickly feel stuffy and overbearing when you've a continuous heat source (such as a computer and everything that goes with it) - especially if it's a decent summer.

At work (I'm in IT) I often get asked questions along the lines of "can't we just stick the noisy server in <some small space, usually a cupboard> where it's nice and cool ?" I then have to try and explain that the small space with no ventilation will quickly not be very cool once we stick a small fan heater in it - and that can be a very difficult concept to get through to some people.