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1 Answer

Most efficient use of 3/4" polyiso on exterior (polyiso is foil faced on both sides)

My home is standard built- 2x3's 16" oc w/craft faced fiberglass ins not very well installed( gaps,etc.). I have enough 3/4" f f polyiso to cover it. FH's recent articles indicate Roxul batts would be best way to insulate, but I already have the foam.

Asked By Victor Brown | Sep 29 16
1 Answer

Is it a good idea to vent a bath fan exhaust out of eyebrow roof?

I originally liked the idea of venting the bath fans out a gable end of the house in order to minimize roof penetrations on the steel roof. I did some research into venting through the main roof soffit vents, and obviously that is not a great idea due to the possibility of drawing moist air back into the roof.

Asked By Adam Peterson | Sep 28 16
2 Answers

New Mitsubishi minisplit wall units


Does anyone had experience with the mitsubishis mini split MSZ-EF model (comes in 9, 12,15, and 18)? They have a slimmer profile than the prior versions. I am having trouble finding information on the EF (or Zen) series that is geared for the US, and am trying to figure out if BTU and Seer ratings are comparable to the FH range.

Thank you!

Asked By Whitney Scurlock | Sep 27 16
2 Answers

Looking for ERV install design suggestions

I am looking to install an ERV (Renewaire EV90P) to my home and am struggling to find people both interested but also qualified (or interested) to tell me the best install configuration and why instead of just dumping the fresh air into the return plenum. I'm considering now doing it myself and having two return vents (kitchen and bedroom) and two fresh air grilles (living room and hallway). Already have 200 CFM range hood ducted to outside and a bathroom exhaust fan with 60 min. timer to let run extra time up to this point. Blower door test showed 1.9 ACH.

Asked By John E. | Sep 27 16
5 Answers

How to encapsulate a brick veneer crawl space?

I am in the process of encapsulating our crawlspace and have a few questions. The house rests on concrete block piers and contains a brick veneer that covers the crawl space and extends below grade. There is a 2-3 inch air gap between the brick and the framing as well as the concrete blocks. The house is located in Climate Zone 3A so plenty of humid air.

Thus far I've installed a 12 mil vapor barrier over the dirt floor and up the sides of the brick wall (leaving a 3 inch gap for termite inspection). I've also closed up and sealed the vents.

Asked By Nate Wofford | Sep 27 16
58 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
6 Answers

Low-e? "Do not scrape glass."

I just installed some high end french doors that came with a sticker warning 'DO NOT SCRAPE GLASS". Does anyone know anything about this? Is it some new kind of low E film, have there been long term problems with scraping low E glass?

Asked By William Goodwin | Sep 24 16
35 Answers

Have many questions about HVAC, insulation, and ventilation

I have many questions about HVAC, insulation and ventilation, but will just start with a few. If we decide on an exhaust-only system for a new build home, does also trying to button up the envelope tight work with that type of ventilation?

We will probably insulate with fiberglass blown in at attic floor because spray foaming the whole attic would be so much more expensive. If we don't insulate at roof, do we need to install a radiant barrier at some location to try to bring the heat down in attic?


Asked By C Clark | Sep 21 16
7 Answers

Air sealing

I am in the process of building a new home in zone 5. We are doing a passive solar house with vaulted ceiling in the living room, kitchen and dining room area and the rest of the house will be flat ceilings. I plan to do blown in cellulose insulation on the flat ceilings and closed cell on the vaulted ceiling. I plan to do 3” of rigid foam insulation on the exterior walls with spary in cellulose (2x6) walls. I am also using Prosoco seam filler for the sheathing and Fast Flash for the flashing.

Asked By Michael Brackett | Sep 23 16
7 Answers

Fiberglass insulation

I read your article on insulation an older home that does not have sheathing behind the ceder lap siding. The house is in southern Missouri so I was planning on 0.75 inch foiled rigid foam board (foil facing the exterior siding with a 0.75 inch air space. My question is should the fiberglass batting have kraft paper or just the fiberglass batting. I was planning on 0.5 inch sheet rock for the interior walls.

Thank you for your time.


Asked By Jim Tune | Sep 6 16
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