Since there is no furnace, not any ductwork in this house, does anyone have a recommendation for an HRV that will work as a spot HRV without any more ductwork than that connecting to the outside air?

-Rosalinda

Posted By Rosalinda on 28 Jul 2010 03:53 PM 
... I have fans and windows that will supply fresh air without problem from March through October, or maybe even November, but for the really cold months of December through February, though I can open a window, or put a hole in the wall for make up air, maybe even using one of those one way flow self closing ducts, letting in icy cold air does not seem the way to go. So what are my options?

I have been looking at the Panasonic FV-04VE1 http://snipurl.com/zxdje which appears to be a spot ERV for fresh air. Will this work? Don't I really need an HRV during the winter in my cold climate? Is there any product out there that might work? Has anyone got a DIY solution for this?

My energy evaluator suggests just using an energy star 110 CFM bathroom fan with a 24 hour timer such as this one http://snipurl.com/zxecq (and that price is silly, they sell in the $185 range) and opening a window or cutting a hole in the wall for make up air. This will satisfy the energy star requirements for ventilation, but still looks pretty inefficient to me from a heating standpoint.

Any advice or suggestion would be much appreciated as always.

-Rosalinda

Rosalinda, I am not a builder, just a home-owner - so take this idea with that in mind. You mention just using a window as OK except in winter due to obvious cold air problems. I wonder if you could use a solar air collector to warm fresh outside air that you then bring into the house. This could work without interior ducting, I would think. Of course it won't work too well at night or during bad weather! Also, I'm not sure if you could really get the incoming (fresh) air up to a decent temp as I've normally read about solar air collectors in the context of recirculating indoor air and heating it in the collector. Maybe with a large well constructed collector and a relatively small air flow it could work(?).
Well, just an idea.
Good luck on your house!

I would think that any HRV would work without ducting inside the house. How happy you are with it might depend on how open the floor plan is and how well you can direct the cooler incoming air so that it doesn't bother anyone.

Decided to go with a Panasonic FV-13vks2 ventilating fan for the exhaust side and a Cape Tamarack damper installed in a passive solar air box for the makeup air in winter. Windows will provide spring ,summer and fall fresh air. Time will tell if this will work, or if it will cost too much warm air loss in winter.

We are currently experiencing one of the most extreme fall/winters with the least amount of sun we have ever had. I still do not have a heating system in the house, so am using a very small electric heater with occasional warm up with a propane garage heater. Between the two, I am managing to keep the house temp around 50, despite temps in the single digits. The temperature in the house is fairly consistent from ground floor to main floor and room to room.

I have pretty much decided on using an AO Smith Vertex 100 50 gallon propane (no NG here) direct vent hot water heater to provide both DHW and the radiant heat through a flat plate exchanger. The Vertex is supposed to be set up to do both, and all the stuff I had read online about them seems positive. My heating contractor is trying to talk me into a Navien on demand combi. They are supposed to come out with a propane model in mid Jan. Any input? I looked at the thread here, Navien NR-180 for Radiant Heating, and as always there are 3 good but differing opinions.

Still several months away from occupancy as other things interfered with work on the house. Hopefully I can get back to it in the next few weeks.

-Rosalinda

You can probably justify geothermal over propane although everyone's numbers are different. Open loop or even a horizontal closed loop should not cost that much if you shop around. If not geo, then air source heat pumps should be cost effective during some periods.

Geothermal is very expensive up front and way too expensive to run. It uses too much electric.

Today I feel as if I have made real progress. The Vertex 100 hot water heater is installed, the propane lines are all run. The propane system was inspected today and the HWH and kitchen range fired and adjusted and all is working.

For propane lines, I ended up running Type L copper through plastic conduit in my floor truss system, connecting to black pipe via brass fittings at either end - HWH at one end on the ground floor, Kitchen range on the other, on the main floor. I did hire a contractor to install the Vertex, install the black pipe, and help me tighten up some of the fittings, but I designed the entire system and purchased all the parts and had it all put together dry for him. He was happy to work with me, so I think I have a go to team now for whatever help I need in finishing the house.

The contractor also installed the Panasonic vent fan for my air exchanges. I still need to build the air intake box.

Next up is the manifold, pump and control system for my radiant heat.

-Rosalinda

Heating system is in and running beautifully. I did a little caulking around the base of the walls on the perimeter of the main floor, since on a windy day it seemed to me there was some air infiltration.

Had my Energy Star evaluation today, and both my evaluator and the guy from NYSERDA showed up (Bret). Bret brought his infrared camera with him so we were really able to see how well everything was sealed and functioning. It all looked really great. There is one spot in the foam roof insulation along the soffit edge that I need to check and another where the wall was changed due to the ceiling/roof rebuild. Other than that all is ship shape.

The blower door test was 612 cu/ft/min @ 50Pa so with my 25637 cu ft, gives a result of 1.432 (if I did my math correctly). Not PassiveHouse - but darned good! All that caulking has paid off. I received an eStar rating of 90 overall, and qualified for the Owner/Builder incentive. Next on to the GRBP program. A point in my favor is that Bret from NYSERDA is one of the folks involved in that program, so he has had a first hand look at what I am doing, so will know the property when it comes up for evaluation.

-Rosalinda

Took the 15 Hour Green Building for Green Building Professionals course through NYSBA and NAHB this past week. Required to qualify for NYSERDA incentives as the owner builder. Some interesting discussions about the changes in eStar 2.5/3 which will require some specific wall structures. If you now build a 2X6 wall it needs to be on 24 inch centers or if 16 oc, have 1.5 inches of foam board on the outside. I gather Dow and the green building science folks have figured out that unless you have 1.5 inches of foam board on the outside (as opposed to less) you will get condensation, but 1.5 will do the trick. One inch is now required on 2X4 construction. Since I would like at some time in the future to get that foam on the outside of my house, I am hoping by the time I am ready, there will be a product on the market that will give the necessary R value but not be so thick.

It was also interesting in how many builders live in leaky, drafty homes - primarily old ones that they have yet to get up to par. One contractor was going to add a second set of windows on the outside rather than move the current ones to accommodate the foam board he was adding to the outside of his walls.

Hoping to get my HERS report soon.

-Rosalinda

I'd be interested in the numbers if you converted your ACH50 to ACH-natural and calculated your annual fuel cost for such leakage. A very rough calculation - $60/year using nat gas.

I am looking forward to getting the HERS report from my evaluator and will post the results. My leakage should be around 0.0716 ACH Natural, but I will have vent fans and makeup air for air exchanges.

I am thinking that 5 to 10,000 btu/hr range for the whole house is a good one. I used approx 5537 btu/hr to keep the house at around 50 degrees f all winter - but that was without furniture, curtains, shades, cooking and people,dogs etc all of which will add btu's. I will probably keep it at around 60 to 65 next winter, but hopefully will have all the missing elements that were lacking this past winter. I am also hoping to charge the ground under the house to as close as I can get it to 70 degrees before we get into the heating season, and will see what effect that will have, if any, in heating the house in the winter. So that will be more like a range of $400 to $800 in propane, unless I can add some alternative ways to heat the water for the radiant floor.

-Rosalinda

I probably wasn't clear about the $60 - that's just to heat the air that is leaking in/out, not the entire heating bill. I was trying to get a rough idea of where air infiltration becomes not worth putting much more effort into it. For example, at this point, it might take a lot of work to cut your infiltration in half - and it might only save $30/year (if you had nat gas).

Congrats on all the aspects of your home.

dogs etc all of which will add btu's.

Ha Ha. What is the efficiency ratio for the conversion of puppy chow-->residential heat? :-)

ROFLOL - a good question on the puppy chow, but then there are all the other benefits and services those pooches provide to add to the BTU conversion.

Thanks Jonr I see what you mean. I guess all you can do is do the best sealing job you can afford and hope you get the result you planned for. In my house it is a balance of the very inexpensive caulking, window and door sealing and foaming I did, and the very expensive 2#cc spray foam in the roof and band joist. No real way to know which did the most and in a way I am sorry I did not make an effort test as I built, using some kind of DIY blower door test.

-Rosalinda

Though I will not get the full written report from my energy evaluator until he comes to do the first inspection for the NYSERDA program, he did tell me that the official house energy star rating was 91, and the HERS rating 45.

Is anyone on this board using the NAHB green rating tool? There sure is a lot of paperwork and documentation needed - almost like writing a thesis. I can see why professional builders would stay away from certification, unless they could see a way to make enough money to cover the hours of work it takes.

-Rosalinda

Had the Certificate of Occupancy inspection today and passed with flying colours. Inspectors were very very impressed overall, and even more so to see what they think is the first 5 star plus, energy star rated house in my county.

I am still working on finishing up stuff for the final inspection for NYSERDA and the NAHB Green scoring tool. Gutters and downspouts should go in next week, and I have to finish insulating the water pipes. Then I have to pull all the documentation together, which might take another month.

There is still plenty of finish work to do, but with this hurdle jumped over, we might just finish it before winter!

I am thinking the deck will have to wait until next year.

-Rosalinda

Congratulations. Sometimes, I think people don't fully appreciate how difficult it can be to be a first adopter, even if it is only in a particular region, like your town or county.

I had to take some ICF blocks and Insuldeck over to the plumbing warehouse the other day. They had never seen it or heard of it.

Had my final energy evaluation today. Earned an NAHB Gold with 621 points. Still have lots of finishing work to do, but we are living in the new house.

-Rosalinda

Would love to see pictures.