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13 Answers

Looking for advice on a new build heating plan

I am trying to figure out the best solution for heating our new home and I would greatly appreciate any suggestion from the wise folks here.

In Mechanicals | Asked By Tim Burke | Nov 24 16
15 Answers

Window mix-up

We are in the process of dramatically upgrading the insulation of our 120 year old farm house and adding on a mudroom/laundry room, new bathroom and replacing the sunporch. We are in northern Michigan (zone 6a). Our original plans had Andersen 400 windows with a U-factor of 0.26 but our builder inadvertently ordered, purchased and installed an older version of the same window that is 0.30 for 12 windows. Everything else about the window is the same -- the difference is a coating on the glass.

In General questions | Asked By Ryan Knight | Nov 22 16
29 Answers

Dense-packed cellulose might go extinct

I apologize for the clickbait title, but it seems all of the insulation contractors in my area are very wary of dense-packed cellulose in walls and often say, "we normally don't do cellulose in walls anymore." Part of their reluctance in my situation is attributed to my dpuble stud 10 1/4" thick walls that are 24" o.c. They think it will settle and bulge out. Still, I think even if I had standard 2x6 walls, 16" o.c., they would all try to convince me to do spray foam and offer a lower price to do it.

In Green products and materials | Asked By Jimmy Nguyen | Nov 14 16
40 Answers

Domestic hot water and space heating

I am trying to put together a system that can deliver domestic hot water and heat the house. The colonial house is in Brooklyn, NY ( zone 7), 29' x 33' and consists of 2 floors + basement. I am doing complete renovation and already removed all walls throughout the house and will use closed cell foam insulation in all walls and roof. I plan to run Pex in joists for both floors and I am thinking of using baseboard in the basement.

My questions are:

In Mechanicals | Asked By Vladimir Polyakov | Nov 3 16
1 Answer

Rebar splicing

I've seen footing rebar tied it two ways. One was the horizontal bar laying side to side at 24" overlaps. The other was horizontal bar facing top to bottom at 24" overlaps.

Which is the right or better way? The top to bottom seemed "cleaner" but not sure which is best?

In General questions | Asked By Peter L | Nov 23 16
1 Answer

Insulation options to add R-value

I had the opportunity to reroof this spring and add exterior rigid foam. I used foil faced polyiso 2.75" thick. Due to time and money constraints I applied a single layer taped and foamed. Through fastened wth .5" OSB cut into 3" strips. A new OSB deck was installed and asphalt shingle roof on top of that.

In Energy efficiency and durability | Asked By David Mosijchuk | Nov 23 16
74 Answers

Sun Bandit solar water heater

Hello. I was reading the article by Martin Holladay entitled "Solar Thermal is Really, Really Dead" and enjoyed the discussions going back and forth on the topic of solar water heating methods. I am planning on building a small 600sq' SIP cabin in the area of Nelson BC (climate zone 6) next year and I found this product listed as being one of the most efficient for heating domestic hot water on the Canada Energy Guide site. It says it can also be used for space heating via a radiant floor system or perhaps radiators.

http://www.sunbandit.us/

In Green products and materials | Asked By Scott Wilson | Oct 21 16
7 Answers

Mold in fiberglass insulation

I have a lookout basement, built in 2009 in climate zone 6, currently unfinished. The above grade framed section of the lookout wall is framed with 2x6s and insulated with fiberglass batts and a poly vapor barrier on the interior side of the wall covering the fiberglass. I have noticed small dark areas in the fiberglass throughout the wall where it meets the poly sheet. The dark spots are very sporadic and appear at first glance to be mold to me, although i have not confirmed this.

Assuming this is a mold issue, what would be the preferred method of replacing the insulation system?

In General questions | Asked By Nick Collins | Nov 23 16
3 Answers

Insulating a brick wall from the inside

Hi,

We have a 100 year old row house in Montreal, (zone 5000). Most walls abut the homes on either side, but we have a bump out in the back with two exposed walls. The walls are two bricks thick, (I think), with plaster on the inside, and I think a layer of drywall on top, (judging by how the walls are actually proud of the original baseboards).

The walls in question are in our bathroom, which gets quite chilly. I'd like to add foam board insulation on top of the walls, and then drywall on top of that again (we can live with the resulting deep sills in the windows).

In Green building techniques | Asked By Sean Lewkiw | Nov 23 16
10 Answers

Attic air barrier/vapor retarder

I'd like to get some feedback on this detail (attached). Background: <700 SF seasonal home in Climate Zone 6. 2x6 at 24" walls are insulated with dense pack cellulose. Rafters are 2x12s at 16"oc (snow country) and ceiling is 2x8 T&G douglas fir laid across 2x10 (actual) bottom chord ~44" apart which are exposed to the living area below. It is 1-1/2 story (just lower level and loft) and I am venting the roof. Heat is radiant slab from tankless boiler augmented with a wood stove when we are there (the only penetration in the ceiling besides the hatch, both sealed well).

In Green building techniques | Asked By Julie Brown | Nov 17 16
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