Ventilation to Non-Outside Wall Bathroom New Build Flat (2011)

[oasisman]

I have a new build flat in Wallington Greater London (Surrey), this is a duplex arrangement with 2 beds and 2 en-suites upstairs. One bathroom has an outside wall with a little window, whereas the other has no window or outside wall.

I'm sure there must be regulations in relation to ventilation, are there any, and if so, what are they?

The boiler I have is a Nibe F470, and you may be wondering why this is relevant, well the builder states the boiler provides adequate ventilation due to its Exhaust Fan feature. However, it's an absolute pain and doesn't make any sense to use it this way except when it's warmer inside than it is outside and one wishes to use the cooling effect (as stated in the Nibe manual). Nibe never state the Exhaust Fan is to be used for ventilation of an enclosed bathroom, since when the vent is switched on, it vents the entire flat, not just a single room. So you can see why it's a bit silly; to vent a nice warm flat in every room just to have a shower!

Cheers.

 

[HandySparks]

It looks from their website that the F470 is an exhaust air heat pump (not a "boiler"). I would expect it to suck air from the hot, wet, rooms (kitchen and bathrooms) and then use the heat energy in that air to heat the building, either by direct hot air or 'wet' radiators or underfloor heating. If configured properly, this system might well be suitable for ventilating the bathrooms.

 

[oasisman]

Yeah, I say it's a boiler when it's not, I know, it's just easier to say that as most people haven't heard of these units before.

It's just the bathroom steams up unless I go all the way downstairs, turn the extraction up to 100% and extract all air out of the entire flat (so not energy efficient), have a shower, and then go all the way back downstairs and turn it off.

Are there any regulations for ventilation..?

It looks from their website that the F470 is an exhaust air heat pump (not a "boiler"). I would expect it to suck air from the hot, wet, rooms (kitchen and bathrooms) and then use the heat energy in that air to heat the building, either by direct hot air or 'wet' radiators or underfloor heating. If configured properly, this system might well be suitable for ventilating the bathrooms.

 

[jon small]

you need to look at PART F & L of the building regs :www.planningportal.gov.uk/uploads/br/BR_PDF_ADF_2010.pdf

here's a useful guide from vent axia : http://www.vent-axia.com/files/catdownloads/part fand l brochure web.pdf

hope this helps - jon

 

[oasisman]

So it seems continuous ventilation (which is what I have using this unit from Nibe) is ok.

However, how does one get over the issue of having to go downstairs to turn it on just to have a shower? With a dedicated fan in the bathroom, usually the fan is tied to the light switch, or a separate switch next to the light switch...

 

[oasisman]

Looking at the government document I've noticed the following in relation to Table 5.2d System 4 - Continuous mechanical supply and extract heat recovery (MVHR)

I believe this relates to the unit I have installed.
It mentions Controls on page 30...
Controls should be set up to operate with occupant intervention (my unit complies).
Controls may have manual or automatic controls to select boost rate (my unit complies).
Any manual boost controls should be provided locally to the spaces being served e.g. Bathrooms and kitchens, as provision of a single centrally located switch may result in fans being left in an inappropriate mode of operation (my unit does not comply - manual controls are located on the unit itself underneath the stairs)

Am I correct in my interpretation of the regulations...?