Posted By: RobLMy friend Wiki who is always right says:" a heat recovery ventilator (HRV) can only transfer sensible heat"

Strictly, your “friend” is right, but misleadingly so. If the outgoing air is cooled to below its dew point condensation will occur. That'll convert latent heat into sensible heat. That released sensible heat can then be transferred to the incoming air.

Mattwardman: Please note I have mentioned more than once during the thread that adapting an existing room for dual purpose is likely to be a good option for existing homes. On new build, building costs arise and folk must spend their budget to suit their priorities. These days there is a mania for en-suit bathrooms, which are expensive luxuries. Not to mention £20,000 fitted kitchens. The ultimate waste is the frequent re-modelling kitchens and bathrooms to satisfy fads of fashion!. When I was a kid the better-off had a bathroom and a 'bath night' once a week. The majority had a tin bath in front the fire and an outside toilet.

The irrationality of current waste is that never did so many people have jobs devoid of dirt yet never was so much daily bathing deemed essential. As to kitchens, when mothers cooked from raw ingredients 3 times a day 7 days a week for large families, the facilities were simple. Real cooking is a rare event in these luxury kitchens.

Quite agree about high humidity and condensation in student flats. As a former student landlord I was surprised at the ignorance of these 'clever' students. The question I used to put to them was "where do you think the water goes to when you dry your clothes over the radiators". The most incredible conversation however was with a student who was convinced someone was tapping into her gas supply, and had trouble understanding how the gas meter measuring cuft became a bill in kWh. After patiently explaining the basics to her, she retorted " I know what I am talking about - we have been taught how to read a gas meter in Energy Studies"

When I built my house I installed my exhaust air source heat pump in a cupboard in the utility room which has a pulley and other rails for hanging washing. I was hoping that it would be a viable alternative to playing roulette with the weather. It works better than I ever imagined. The heat pump dehumidifies the utility room (and the shower rooms), captures most of the energy that's used in the drying process and deposits it back in the hot water cylinder.