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3 Answers

HVAC Systems

Hi all,

Last week I asked my first question about how to improve my building envelope and reduce mech system costs. using coolcalc.com, I simulated a number of manual J scenarios, I think I have the envelope options down to 1-3 things and will await results from my energy consultant.

The question now remains as to how to best heat & cool my home. On that post, many people suggested Chilltrix, but one poster suggested Implementation risk. They didn't really explain what they meant by that.

Asked By Matthew Hicks | Mar 25 17
12 Answers

Saving a wet crawlspace

Hello All.

I am a long time fan of Fine Home Building, and have been a practicing contractor for the last 5 years here in Halifax, Nova Scotia, Canada.

I have been asked by a client of mine to try and address a moisture issue in the crawl space of their home here in Halifax.

Asked By Nick Rudnicki | Mar 19 17
1 Answer

Energy efficient attic exhaust fan?

Where could I find an energy efficient roof exhaust fan. I have power in the attic so no need for solar. The attic temperature in the summer is well above the outside temps. I presently have ventilation along the ridge and some under the eves.

Asked By housenerd | Mar 25 17
5 Answers

Replacement boiler sizing based on past usage

I'm looking for some reassurance and validation before I pull the trigger on an expensive purchase.

I currently have a 40+ year old, 137,000 BTUh oil boiler that is getting long in the tooth due to substantial corrosion. I have done many efficiency upgrades to my home. I am very interested in replacing the boiler with an electric boiler as the boiler I have now short cycles since I have improved the efficiency of the home so much.

Asked By Efficiency Fan | Mar 23 17
7 Answers

PV panels on the roof or in the yard?

I am in the process of designing a new house and I am trying to decide whether or not to place the PV panels on the roof or in the yard. I would assume it is more cost efficicent to have the panels installed on the roof by avoiding pouring the concrete pad and having the power trench ran to the panels. I have not started getting price quotes for either system as of yet but I am hoping to get into that soon. I would just like to make a decision as to where I want the panels to go first. One side of the roof of the house will be facing southwest.

Asked By user-6801629 | Mar 24 17
2 Answers

ERVs and dusty homes

Do ERVs work well in dusty homes?

I'm building in the country in a windy field. I have have 200lbs of pets, and they kick up a lot of fur and dust. The return on the forced air system at my old place clogged up quite quickly, and that was with a big, deep filter.

I'm concerned that the little filters (or the cores) in an ERV or HRV will clog up and make the airflow imbalanced. If I would end up with a chronically imbalanced system, would I be better going exhaust only?


Asked By John Ranson | Mar 25 17
4 Answers

2 layers vs 1 of outsulation?

Greetings from Fort Worth, TX!

We are finalizing our house layout and I have been looking into various wall systems. I've about settled on 2x6 advanced framing dense packed - Zip Wall or OSB with Wrap - 2" foil faced iso tapped.

This should give me roughly a R-25 wall.

My question is; not including labor, material cost is roughly 50% higher to do two layers of 1" vs 1 layer of 2". If I have a WRB and air barrier under the foam is it really necessary to have two layers?

Asked By Adam Fuller | Mar 24 17
12 Answers

ERV and flex duct

We're planning to install a Renewaire EV90P ERV with dedicated ductwork in our new 1900 sq ft home. It's going to be a budgetary strain to install hard pipe for all the entire system. So I'm hoping we can get away with a rigid duct for a trunk (running parallel to floor trusses) and then 6 inch flex duct going out to the exhaust and supply registers (through the webs of the floor trusses) - this is what the HVAC contractor is recommending, but I'm concerned about this small unit being able to handle the additional resistance to air flow from the flex duct.

Asked By William Costello | Mar 22 17
6 Answers

Insulating floor of an old barn

I have an 1804 bank barn and plan to use the lower level as a shop. Since dirt falls through the floorboards above anytime I walk upstairs, I need to think about insulating as a first step.

The easy thing would be to spray open-cell foam on the ceiling (bottom of 1.5" floorboards); but, I'm concerned that the foam won't maintain an air seal when people and machinery move around upstairs.

Asked By Michael Stelts | Mar 22 17
1 Answer

Another Question over Spray foaming Cathedral Attic

Hi Martin.
Sharing more info and hoping for some suggestions. My cathedral vault cavities (drywall) in the attic only goes up about 2/3% the underside of the roof decking. The rest is open attic space where studs and roof decking exposed. See picture attached. Any suggestions on how to tackle this situation when spray foaming the attic?

Asked By uberaustin | Mar 24 17
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