HRV (Heat Recovery Ventillation System) - value for money?

Hi all.

Planning to start my build in a few weeks, going with ICF (Insulated Concrete Forms).

I was planning to install HRV (Heat Recovery Ventillation), but am curious about the cost effectiveness.

I have used the DEAP (Dwelling Energy Assessment Procedure) calculation software to determine the energy rating of the house, and compared the results both with and without HRV.

Even when I do this for a very good result in the blower door test, the estimated cost / year doesn't change dramatically with the greatest difference being less than €100 per year (very airtight). At a cost of approx €6,000 for the HRV system, this is a payback of over 60 years!

Does this sound right or might I be doing something wrong?

Re: HRV - value for money?

I think the benefits of a HRV system relate to a healthier house rather than air tightness. From anecdotal evidence and form reading what other AAM posters have said, the air quality in a house is greatly improved with a HRV system, leading to less dust and fewer infections, colds and respiratory infections. I was quoted €4500 recently for a HRV system which included installation. As our 2 year-old has asthma, it's something I will definitely be installing when my renovation takes place in the summer.

Re: HRV - value for money?

4.5K seems a great deal, can you pm the installer/supplier

Re: HRV - value for money?

think there is something up with DEAP on this matter.

im no expert at all but there was a discussion on this on boards.ie construction section and people there were curious about the fact that there is little change in the energy rating. dont think new regulations from july are implemented in current DEAP software

hi! 4.5 K is a great quote as I've recently been quoted 8K for a HRV system. What company quoted you the 4.5 K and is it a new build?

The general advice is that you need to get your airtightness up to a very high standard before HRV is optimally effective. As airtightness goes down (or up as it's measured in air changes per hour per square metre) the effectiveness of HRV goes down.

However, if you do not fit mechanical ventilation, you need to provide passive ventilation, usually via the holes in the walls or trickle vents, to meet building regulations. These can be draughty, noisy and inefficient.

HRV can do much to improve internal air quality as the incoming air is filtered which removes many pollens, insects etc. I'm not sure it'll ever have a reasonable payback time per se but the qualitative improvements are noticeable. Note that HRV also replaces extractors in bathrooms to remove moist air but you can't use it to extract cooking fumes.

Things to watch:
- not compatible with open fires - you need room-sealed stoves
- get the rigid ducting not the flexible stuff
- get a boost function for showers etc.
- get a summer core which does not do heat exchange
- put an extract in your laundry/utility room so you can dry clothes

I don't think the software works correctly with HRV as it applies a default value all the time.

We have HRV in our build from 2007. It's one feature, along with all the CAT5, we wouldn't be without.

Good luck with the build
SSE

Heat Recovery can be fantastic but it depends on the unit you buy.

Any more information on products,prices and free information just ask as it's kinda linked to my job as I'm a renewable Energy trainer.

Building in Cork, can anybody recommend suppliers/installers

Thanks in advance

I am quoted 7.5k for install please share the suppliers who are coming in at 4.5k as 7.5k is a lot of money for what is essentially a big fan.