Kitchen and Bathroom Ventilation

[dizz]

I have just bought a top floor flat, and when I went into the loft space, noticed that the ventilation for the kitchen just goes into the loft, and that I don't appear to have at all for the bathroom. Can I get ventilation installed for the bathroom and the kitchen and use the same "feed" to take the air to the outside wall?

 

[mointainwalker]

If you are saying that the ventilation you have simply vents into the loft, that is bad. It should vent to outside otherwise you will suffer from condensation

You could use the same feed as long as whoever installs it takes care to do so in such a way that waste air from one area is not cross-fed to the other.

 

[dizz]

Yes I am saying that - awful isn't it? And thanks for the reply.

 

[dizz]

I am now looking at how I should best vent out in the roof space.

I cold vent out onto the front of the house, the side or the back.

1. Is there a maximum distance I can vent horizontally?
2. I guess that once horizontal, the vent should not elevate?
3. Is there a rule about venting onto the adjacent property - The side option will be to vent out (at high level) onto the car park of a commercial property?

 

[dizz]

OK - I have found Appendix E of Part F, and I have the answers to 1& 2.

Anybody have ideas on 3 above please?

 

[dizz]

I am venting from Kitchen and Bathroom connecting to the same ducting - How would I prevent kitchen venting to bathroom and vice versa? I assume there is some sort of gravity flap or such like - can anyone point me to a product please?

 

[mointainwalker]

You don't need vents and flaps : use something free and infallible like gravity.

Just ensure that your vent pipe has a down gradient on it where you bring in the second pipe. Also use a 45 o angled connector so that the air from the joining pipe flows nicely into the main pipe.

I am assuming here ( hopefully not wrongly ) that you are using rigid PVC pipe for your vents and not that crap concertina rubbish.

 

[dizz]

ok - Thanks - I plan to have the bathroom exhaust going to the outside wall on a down gradient. The kitchen (which lies between the bathroom and outside wall will have a cooker hood (this will be about vertially below the rigid PVC pipe. So rather than connect straight up into it should I run a pipe from the kitchen coker hood, up alongside the bathroom one, using another PVC pipe, and then follow a similar down gradient path as the other pipe (two pipes directed towards the outside wall, then at some stage before, filter into the bathroom pipe using a 45, so one pipe goes to the outside?

 

[mointainwalker]

Basically yes.

You absolutely must not join the cooker extract vertically into the horizintal bathroom vent as that guarantees cross-contamination.

How long are these pipes and where is the vent fan/unit ? What diameter is cooker extract ( I ask because lots are 150 mm) ?

 

[dizz]

The run of pipe from the bathroom to the outside wall is about 2.5 metres max. The cooker will be between the bathroom and the outside wall, say about 1.5 metres away from the outside wall. So I have about 1.5 metres to go up, alongside and into the bathroom pipe. Diameter is 120mm.

If I tee right near to the outside wall

http://www.screwfix.com/prods/77712/Heating-Cooling/Ducting/Circular-T-Piece-100mm-4

Then add a 90 is that OK?