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3 Answers

Exhaust-only ventilation in Maine?

Wondering if I can use an exhaust-only ventilation system in a new home constructed of SIP panels that is heated by 1 to 2 wood stoves depending on outside temperature. I have 6" duct work going the two bathrooms and also installed 6" ducts to be connected to an HRV for fresh air.

Recently I have been wondering whether it is cost effective or necessary to install the HRV. It seems as though the exhaust only route would be fine, but I'm wondering if there will be an issue using wood stoves and creating negative pressure with the exhaust fan.

Thanks to all in advance,

In Mechanicals | Asked By Ben Geissinger | Jan 18 14
2 Answers

Is creating vapour resistant barrier on both inside and outside of a cellulose fill wall advisable?

Reading the Fine Building Mag artical 'Designed for Success' (link below) I noticed the 16" double stud wall assembly had a layer of spray foam on the exterior sheeting (couple of inches) with the remaining wall filled with dense pack cellilos and closed with a 6mm poly vapor barrier . With the closed cell spray foam and the poly rap I am assuming moister in the wall is not a concern - why? Is this wall type safe in all climate zones including extream cold - we get 8000 hdd with many days sub -40. Why isn't the due point a consern? Science based feedback would be helpful.

In Energy efficiency and durability | Asked By Mark Henry | Jan 18 14
7 Answers

Insulation gap in or out?

Installing a 5 1/2 batt of Roxul in a 6" wall. Does it matter where the batt ends up? Up against the sheathing or up against the drywall?

In General questions | Asked By darren williams | Jan 6 14
1 Answer

Drywall recommendations?

I've been researching the various options for drywall and would love to get any thoughts or recommendations people might have. I'm trying to avoid buying into the latest drywall sales pitch, I.e. CertainTeed has a "airrenew" version of drywall and they registered the slogan:) maybe it's real and I'm just too jaded by sales and marketing. Does anyone have experience with this drywall? It supposedly will take VOC out of the air in your home for 75 yrs.

In Green products and materials | Asked By Jonah Griffith | Jan 20 14
18 Answers

Would 2x8 studs filled with dense-packed cellulose and 2 in. rigid foam over the sheathing work in Zone 5?

I'm located in climate zone 5 (Portland, Maine).

The 4 inches of foam that people seem to like over 2x6s seems quite a bit more troublesome from a detail point of view. Sure, 2x8s would cost more, but cellulose is a lot cheaper and more environmentally friendly than foam.

In a related question, what about solid wood sheathing, which is more environmentally friendly than OSB or plywood? Could one get it tight enough with taped housewrap?

In Energy efficiency and durability | Asked By KEVIN ZORSKI | Jan 2 14
2 Answers

Minisplit heat pump condenser in the attic?

Can I put the condenser in the attic?

In General questions | Asked By Anthony Musso | Jan 20 14
4 Answers

Is whole house radiant floor heating effective in the real world?

Is whole house radiant floor heating effective in the real world?

Calling out to homeowners with radiant floor heating...

I am looking at constructing a new home in New England, specifically the metro Boston area. A large house approx 4,500 sq ft on 3 floors, I would like to use radiant floor heating throughout, mainly for comfort but secondarily for hopefully lower energy bills.

The house would be well insulated and my concern is that I am hearing of issues of radiant heat and well insulated homes.

In Energy efficiency and durability | Asked By Pawan Bajaj | Jan 19 14
24 Answers

How can I best retrofit and insulate an existing cathedral ceiling?

Hi Gentlemen/women:

Thanks for this excellent blog. I have a 22 year old home with a "great room" and cathedral ceiling. From inside it is v-groove pine, probably no taped sheetrock beneath but I wasn't around when it was built, and 12 inch fiberglass with kraft paper. (It has the built up/down rafters you have mentioned). There is a vented area above fiberglass, probably about an inch and a half (soffit and roof vents; there are a couple of dormers). One can see ice and icecles on the roof, and the place takes alot of wood (and propane) to heat. Oh, I'm in northern Vermont, zone 6.

In Energy efficiency and durability | Asked By Howard Gentler | Jan 4 14
2 Answers

Partial retrofit?

First, thanks to everyone for all of the advice and knowledge I've received here. This site and the forums are excellent.

I am the homeowner - knowledgeable, some prior construction experience, but not expert.

In Energy efficiency and durability | Asked By J Eringis | Jan 15 14
9 Answers

Minisplit air handling

I have a new home now for 8 months that has 3 stories and 1 mini split unit on each floor. I have noticed that there is an abnormally large amounts of dust in the home. I had an idea that this dust was from not having enough air movement in the home. Has anyone else experienced this or have any suggestions when using mini split systems?

In Mechanicals | Asked By Jon Lane | Jan 15 14
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