HRV or other ventilation solution for period home

cyberspider

I live in a large early Victorian over basement Detached house. We have done quite a bit of work on insulation and heating:

• 340mm sheepswool insulation in attic
• New Double glazed windows in House
• Better zoned heating controller (Evohome)

There are old, poor air vents in the bathrooms that are noisy and don't work very well. We also have high humidity in the basement and a few other rooms.

I want to replace the bathroom fans and also introduce a system to cycle air in basement plus address humid air in one other room. One solution would be a HRV system but I know that the house is not well sealed e.g. fireplaces in all rooms.


Would any of you have recommendations on whether a HRV is a waste of money and effort to install and what the best options would be?

BryanF

http://www.boards.ie/vbulletin/showthread.php?t=2057620852

cyberspider

Thanks BryanF,

I had spotted that alright and had looked at that solution in alright but looking to see if there are other options and what peoples general opinion

Dardania

My opinion, having lived with the Aereco DCV system for the past 4 years, is it's great for controlling humidity. And silent. I don t open windows int he house anymore, and the house is always cosy yet fresh.

Only issue I find is that one must be careful with vent placement in bedrooms, so as to prevent draughts. THis is noticeable in winter when the outside air is cold - sure the Aereco system will barely have a trickle of air movement if you switch the affected vent down to it's minimum, but if the temp of that trickle is cold, it can be noticeable.
SOlution - put the vent quite high up, and consider the air path.

bertie 56

Check at Lunos e² ventilation system . It's basically a small heat recovery ventilation unit that fit in a hole in the wall .
I don't know if it works well, but at least you won't be heating the birds outside like if you have a Aereco or equivalent system !

Dardania

bertie 56 wrote: »

Check at Lunos e ventilation system . It's basically a small heat recovery ventilation unit that fit in a hole in the wall .
I don't know if it works well, but at least you won't be heating the birds outside like if you have a Aereco or equivalent system !

http://www.lunos.de/media/medialibrary/LUNOS-WRG-2016-UKVFinalweb.pdf page 9

interesting concept - a pair per room, alternating duty with each other

ANd the e90 for kitchens & bathrooms too, with an integrated HX in the wall

The fact it's decentralised is excellent. Good for sound attenuation to - maybe you wouldn't need door undercuts etc. as with the aereco system

I'd wonder about cost (including electrical supplied to each wall ope) being a big issue - it doesn't look cheap...

Also, to what degree of air tightness does this start becoming ineffective at (period homes not being known for their air tightness)

One can buy an awful lot of gas to heat the rooms and the birds with the cost of 2 no. 230V supplies chased up the walls in each room!

murphaph

The Aereco system needs just a small gap under the doors, which in most cases will be there anyway but an Aereco system has no business in a period property (assuming not particularly air tight) as it works by forming a vacuum in the property and only drawing air in through the Aereco vents (which are controlled by humidity in the room they are installed in). This type of system clearly can't work as intended if air can just bypass these regulated vents and enter through the usual cracks and gaps in an older building. It's no longer "demand controlled" when that happens.

Dardania

murphaph wrote: »

The Aereco system needs just a small gap under the doors, which in most cases will be there anyway but an Aereco system has no business in a period property (assuming not particularly air tight) as it works by forming a vacuum in the property and only drawing air in through the Aereco vents (which are controlled by humidity in the room they are installed in). This type of system clearly can't work as intended if air can just bypass these regulated vents and enter through the usual cracks and gaps in an older building. It's no longer "demand controlled" when that happens.

I agree with you, to a point - the exhaust units of that system are also humidity controlled, so these will close down when the room is dry enough, and open when new fresh air is required to combat humidity.
It's not optimal, but it would work.

What ventilation would you recommend for a period building, to overcome humidity issues?

murphaph

Dardania wrote: »

What ventilation would you recommend for a period building, to overcome humidity issues?

Honestly I wouldn't feel qualified to make a recommendation. I just know that the Aereco system we have in our airtight house could not function properly if the house wasn't airtight. A centralised system is difficult to retrofit so the options are limited.

To be honest most Irish have no idea how to air their houses using the windows and that's the first step to understanding what is needed from a mechanical solution. In Summer for example it is often counterproductive to air during the day as the outside air will contain more moisture per m³ than the inside air! The trick is often to air at night after the outside air dries (by cooling and the moisture condensing as dew outside) and can take on more moisture from inside. In winter the air is always dry enough to air day or night but only by opening opposing windows wide to push the air through fast and not let the building and fixtures and fittings cool down.

bertie 56

I really don't understand the concept of having an airtight house if it's to make holes in every wall that would let cold air entering...
The fact that this is monitored doesn't make it a lot more clever...

Airtightness make sense if you recover the heat you are loosing through ventilation : no cold air entering inside the house.
If not, just don't do it airtight, let the gaps and cracks that will ventilate the house, and get a dehumidifier ! And pay your kerosen bill...

OP, did you check for the causes of humidity in basement ? ( French drain ??? )

murphaph

bertie 56 wrote: »

I really don't understand the concept of having an airtight house if it's to make holes in every wall that would let cold air entering...
The fact that this is monitored doesn't make it a lot more clever...

It does though, that's the thing.

just do it

Murphaph

Is the system working well for you?

murphaph

just do it wrote: »

Murphaph

Is the system working well for you?

It's too early to say to be honest. We've not even moved in yet. I hope it will live up to my expectations. Have some concerns about dew point in cellar in Summer given the higher humidity. In winter I expect it to function very well. But again, our house is very air tight (n50 if 0.8) which is a prerequisite IMO.