hendriQ

Oh I see. So you're saying that the supply air to the utility room could come from outside the house itself, rather than from the adjacent kitchen? If that's what you're saying then I'm even more confused as I thought for MVHR to work one had to be airtight against the outside so that one had full control of incoming and outgoing air. Sorry I'm being really dense here.

If the BCO has any common sense, he will surely realise that there is no disadvantage to what I'm suggesting. If anything, it will provide more circulation of air to the utility room, which given its use is probably one of the rooms that needs most ventilation in the house. But I take your point that no all BCOs have a great deal of common sense. I'm not sure I follow your suggestion. What's a kickboard? Is it the part of the door one would kick if one wanted to open it with one's foot? I'm not entirely sure what you're suggesting. But unless it's airtight, the sound will leak through. Another possibility is that if a door is not actually required between a utility room and a kitchen (does anybody know what the regs say about that) then I could leave the door off completely and add it after the BCO approves the build.

Good to know. In this situation, is it better to have the supply in the ceiling by the window and the extract close to the floor on the opposite wall, or vice versa?

I'm keen to have an airtight sound insulating seal on the doorframe between the kitchen/open-plan lounge and the utility room. I was going to fit one of these at the base of the door and then rubber seals on the door frame, as well as a door closer. The reason for this is that we do a lot of laundry and don't want to hear it when we are watching TV or having dinner. But having no gap under the door would obviously not be compatible with the MVHR system we are also installing as part of our refurb. I can think of two solutions to this that won't compromise the sound isolation I want: Have both supply and extract vents in the utility room so that that room is separate from the rest of the system - would this work? It would be an independent area, albeit with ocassional leakage between it and the adjacent kitchen whenever the door was opened, but that might only happen 4 - 6 times a day for the amount of time it takes to go through the door (because of the door closer) so maybe 4 seconds each time. Install trickle vents in the utility room window, a regular extractor fan, and forget about running MVHR into the utility room at all. I am getting a new window anyway, so I could specify it with trickle vents if I wanted to. I would prefer to go with option 1 as that way I still get the benefit of MVHR in the utility room, and it will be a lot more energy efficient as the machines in there, particularly the tumble dryer generates a lot of heat. A lot of people on this forum also comment on how easy it is to dry clothes on a rack with MVHR and we will have a small rack in that utility room - although our main source of drying is still the tumble dryer. In case it's relevant, the dimensions of the utility room are about 5.7 m2 in floor area and about 2.4m in floor height, so total volume about 13.7m3. The adjacent kitchen/lounge/tv area is about 8 times that. The utility room is small, but being a fairly narrow trianglular space, there is room to have the extract about 2.7m away from the supply, with the supply still being quite close to the window to avoid condensation. Another thought I had which might improve the flow of air in that room, is that I could site the extract vent low down, near the floor, so that air passed across from there diagonally up to the supply above the window - or vice versa. Not sure which is better, but thought supply typically goes above glazing to replicate the function of a trickle vent.

I too love switches and sockets. Nice way to add warmth to a house, particularly if the decor is a bit neutral. Helpful to have the USB sockets for the ones near the bed / that spot in your living room you sit to watch TV. Check out https://www.busterandpunch.com/product-category/electricity/

I think it's more to do with his larger than average colon (he had a colonoscopy a few years ago and they discovered this - apparently completely safe genetic abnormality).

Interesting option @Mr Punter. A similar, but fairly different idea is the Geberit DuoFresh Odour Extraction Module. This recycles the smells through a carbon filter, and neatly fits concealed behind the flush button plate. Anyone have any experience of this sytem?

This is brilliant. I would absolutely love it if my husband did all his toiletting outside. Not sure today is the best weather for it mind you.

I'm a newbie to MVHR but I have largely been converted and am looking forward to installing a system later this year. One thing I'm trying to work out is the optimal positioning of the extract vents in the bathrooms. I got one of those free designs from a company, and they have put all the extract vents in the bathrooms directly above the bathtub/showering area as they are obviously trying to mitigate the humidity from the hot water. These positions are somewhat sheltered from the rest of the bathroom due to large floor to ceiling shower screens. For the smaller bathroom in our house, I'm not too bothered, but for the bigger one, which is our ensuite, I'm wondering if that is an optimal way to ventilate the whole bathroom, or if it will result in leakage of smells into the bedroom. My husband will regularly leave what can only be described as "nuclear" smell in the bathroom and so I had asked him to install a regular extractor fan like we have at the moment in the bathroom as well as the MVHR. He says this is a no-no because it will completely unbalance the system as well as introduce a potential air leak. I think there are some clever extractor fan covers that close to be fully airtight such as the airflow icon range, but he says it still will mess up the MVHR. So a second option is to either move the MVHR extract vent so it is directly above the toilet, or have two vents, one for the toilet and one for the shower. The bathroom I'm thinking about is about 7.5m2 with a floor height of about 2.6m2, so a volume of 19.5m3. The radial ducting kit we were going to get has two size options: 65mm diameter which are rated for 23m3 per hour max flow 75mm diameter which are rated for 30m3 per hour max flow There is also a larger diameter ducting pipe available, but I don't think we have room for it. Alternatively, a third option is an oblong pipe with is sort of a smoothed out hemispherical shape and only 52mm high but much wider (about 150mm) which offers a maximum flow rate of 45m3 per hour, but I'm assuming that it's shape means it's not as efficient as a circular option We are planning on running the MVHR unit on its lowest setting to minimise noise and save energy, so I doubt we will get very close to those maximum flow rates. Would it make sense to have 2 x 65mm ducts for that bathroom, or will it make it too noisy? The distance from the MVHR unit (which I understand is a factor in noise calculation) is not much. Maybe 3m to the position in the ceiling just above the shower area, or 4.5m to get it closer to the site of nuclear explosions. I know there is a boost function, but I'm keen not to rely on this as when my husband has a late night nuclear explosion, the boost noise might cause noise that will bother others. During the day, that's less of an issue, but he is more of a night time pooper.