The use of a single room MVHR – are they any good?

[Anonymous]

Good evening,
I am currently designing what I would describe as 'eco cabins' which i am trying to detail to the passivhaus standard. One of the issues i've come across is how to ventilate the space which I intend to make into an 'air tight' box. MVHR seems to be an appropriate way of doing this however i'd like to know if its suitable for a relatively small, single room space such as a this.
The cabins will be a living / sleeping space only (no kitchen or bathroom) and only 40-50m2 in plan area.
Does anyone have any experience in MVHR systems of this nature – are they too loud for a bedroom environment? I've also read that there may be performance issue with a single room MVHR unit under external windy conditions – that the wind can create a backdraft through the unit and you lose any advantages of the heat recovery aspect.
Any thoughts or experience with this would be greatly appreciated.

Thanks,
Richard

[David Olivier]

Well, in the late 1970s the US DOE tested some and LBL tested some and they found significant short circuiting

Not surprised.

I am increasingly sceptical that MVHR can be beneficial in small buildings in relation to MEV, given the economies of scale and the limited value in UK conditions of the heat to be recovered in relation to the full rate electricity which operates the fan/s.

[Mark Siddall]

For units so small you'll be challenged to achieve Passivhaus (do the PHPP to verify), nonetheless you could create a good super insulated cabin.

The Lunos is an interesting option for small units. There are a growing number of suppliers. I've linked to one below:
http://www.partel.co.uk/product-details.php?ID=242

Noise ratings are fine. Though there is a risk of wind blow through undermining actual performance.

Mark

[Author]

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