Please recommend a single room MVHR

[Triggaaar]

Hi all

 

I've been building a single story extension, which has enlarged our kitchen into an open plan kitchen/living/diner of about 70m2. The rest of the house is 100 years old, so fairly leaky (I have reduced some leaks, but I haven't been attempting to make it airtight).

 

The room has no windows, but has large glass sliding doors (6.7m x 2.7m). These do not have trickle vents.

 

From reading on here I think the airflow calculation I need to do is internal floor area * 0.3 l/s/m2. So 70 * 0.3 = 21 l/s = 75.6 m3/hr.

 

The building control notes I've received say:

Part F
1. Provide 5000mm2 background/trickle ventilation per habitable room and 2500mm2 to kitchen.
2. Provide mechanical ventilation in the Kitchen at a rate of 60 l/s or 30 l/s via a cooker hood.

 

I'm hoping I can replace 1. (the trickle ventilation) with MVHR.

I'm planning to have the cooker hood on circulate (just to remove the grease), and hoping point 2 is also covered by the MVHR.

 

Could anyone advice is I'm on track with the 75.6m3 calculation, and what single room unit would be suitable?

I'd like to DIY install, putting the unit above the false ceiling in the utility room, and running an inlet and outlet pipe over the new kitchen.

 

Many thanks

[Triggaaar]

The lack of replies is making me wonder if I'm going about this the wrong way, and no one wants to say anything? Is a single room MVHR the wrong solution?

 

Thanks

[ProDave]

There are "single room" mvhr units but they tend to be intended for a small room and have just one hole in the wall and input and extract from the same point.

 

I would suspect you would be better looking at the smallest of the normal MVHR units rather than a "single room" unit so you can extract from the kitchen end and fresh air in to the living room end,.  You might only end up with 1 or 2 inlet and outlet vents.

[Triggaaar]

7 hours ago, ProDave said:

There are "single room" mvhr units but they tend to be intended for a small room and have just one hole in the wall and input and extract from the same point.

 

I would suspect you would be better looking at the smallest of the normal MVHR units rather than a "single room" unit so you can extract from the kitchen end and fresh air in to the living room end,.  You might only end up with 1 or 2 inlet and outlet vents.

Thank you for the reply, it's much appreciated.

 

I was thinking of a unit that had separate holes in the wall, as you suggest. I was thinking of something like this: https://www.bpcventilation.com/komfort-d105-a

and not something like this: https://www.bpcventilation.com/vent-axia-tempra-htp

 

I hadn't thought of just getting a bigger unit and only using two of the connections (1 in, 1 out), so I'll consider that too, thanks.

 

Although I'd like to do as you suggest, and have the extract by the cooking area, and the inlet in the living area, I have an ideal location for the unit in the adjacent utility room, but much of the extension will be cut off from it by large supporting steels (supporting the room above). I can have an extract by the kitchen cooking area, and an inlet 4.5m away, nearer the entrance to the room (the entrance is a few metres after the door). It's not ideal, but I think I have to accept that I can't have the ideal situation, but rather I can hope to achieve something that's better than just having trickle vents in the room.

 

Given that I don't think my situation is ideal, I don't want to spend too much on the unit. I'm hoping for something fairly basic, that does a reasonable job, and hopefully lasts well enough. Are there any actual units anyone could recommend?

[Triggaaar]

These are some of the units I'm looking at:

 

The cheapest, at £222, not including any ducting etc. It's not as efficient as the units I've seen others here use, but I presume it's still better than just having trickle vents?

https://www.bpcventilation.com/komfort-d105-a

 

And then a few units for between £770 and £890

https://www.extractorfanworld.co.uk/domus-ventilation-hrxe-mvhr-unit-with-summer-bypass-4556-p.asp

https://www.bpcventilation.com/airflow-duplexvent-bv400

https://www.bpcventilation.com/silavent-hrxd

https://www.bpcventilation.com/vent-axia-integra

 

Some of these can do more than one room, should I wish to add to the system later.

 

Has anyone got any experience of any of these brands, and any recommendations?

[tanneja]

@Triggaaar what decisions did you make in the end please? Thanks