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0 Answers

Installation of a firebox in a very old stone fireplace that is on an external stone wall and is very damp.

Do I install a vapour barrier first and then rock wool or ceramic wool with aluminium foil in order to insulate the interior of the existing fireplace? would I use similar techniques to the techniques of shower construction e.g.. backboard etc?

In Green products and materials | Asked By Marina Stass | Jan 16 17
15 Answers

Lunos e2 ductless HRV system vs. ducted system

I am building a net zero house, 2000 SF, 2 stories. Can you tell me the pros and cons of the Lunos e2 ductless HRV system vs. a ducted system? The rep told me that 3 pairs of the Lunos e2 would be about right.

In Mechanicals | Asked By Courtney McCracken | Dec 8 16
18 Answers

Dry heat myth?

Every now and then, I hear people refer to how nice the heat is from a wood stove in our climate (marine zone 4), because it produces such a "dry heat." Whenever I hear that, I think to myself "combustion actually produces moisture, so I don't think wood stoves are particularly dry." I reason further, in my mind, that the only drying effect a wood stove may have on the interior humidity of a home would likely be a result of the tendency for wood stoves to grossly overheat one area of the home, which would drastically reduce the relative humidity in the air, thus averaging out to reduce th

In General questions | Asked By Burke Stoller | Jan 11 17
1 Answer

Are polyisocyanurate materials considered Vapor Barriers and o be avoided for insulating Basements?

I live in Central Minnesota. Our home was newly built roughly 3 years ago. It was not insulated on the exterior, but foil-faced DOW Thermax Sheathing was installed on the entire basement interior. This has a permeability rating of 0.03. This is basically an impermeable material. If we want to avoid moisture problems when finishing our basement, do we need to take this down and put up something with more permeability like EPS? We do try keep the humidity below 50 or 55 degrees in the basement.

In Building Code Questions | Asked By Andrea Zimpelmann | Jan 15 17
9 Answers

Insulation for vaulted ceiling

We re-roofed our house this summer and found a lot of damage over our family room with a vaulted ceiling. We replaced the plywood and are now redoing the underside. The roof has a roof ridge vent and ventilation holes in the soffits. We are creating on-site baffles with 1" rigid foam boards. We are planning to use R30C insulation which is denser for cathedral ceilings. The question is do we use faced or unfaced, and do we need to use plastic sheeting as a vapor barrier? We want to get it right this time!

In GBA Pro help | Asked By Kim Howard | Nov 22 16
58 Answers

Mitsubishi minisplit 8-head system is not keeping up

Back in mid-November 2016, we had a Mitsubishi Hyper Heat MINI Split installed in our house after opening up the first floor of our home and installing some beams to make it more open. We lost duct work feeding the second floor, and had to come up with a solution. We decided on a Mitsubishi ductless system, since I had a smaller version installed in our detached garage and was very happy with it. My uncle did the garage, while I went with one of the Mitsubishi Diamond Dealers to handle our house. After 3 quotes, we decided on a company and proceeded.

In GBA Pro help | Asked By Andrew Simpson | Jan 6 17
0 Answers

Insulating an historic house's attic

Hi all!

I live in Montgomery County, PA, which is at the northern edge of the 4-A climate zone according to the map on this site.

In Plans Review | Asked By Robin Klingsberg | Jan 15 17
5 Answers

What is correct installation of rigid foam board on roof, at seams of each panel?

What is the correct means to seal the seams between foam board applied on top of roof sheathing? What is the impact of incorrect sealing? Background: we contracted with a roofer to apply 4" of Atlas nailbase on top of the roof sheathing, before shingling. I happened to look at the roof on a recent cold morning and noticed gridmarks on the roof, indicating areas where frost had either melted, or had not formed, due to heat loss between the seams of the nailbase. I would think if the seams had been sealed correctly there would be no visible frost lines.

In Energy efficiency and durability | Asked By Jim Berry | Jan 11 17
8 Answers

Another "help me design a wall" thread

I've read wall build articles here but I'm still ambiguous as to the placement of barriers. I've also watched Dana's series titled, "Extreme 10 foot or less snowy knoll patch skiing", but couldn't find any relevant information there.

Zone 5. Inside to out: (sealed?) Drywall | 2X6 studs sealed with Ecoseal and filled with dense pack | either OSB or ZIP taped | 3" poly foam taped | rain screen, vinyl siding.

From what I've learned here this wall will need to dry to the interior.

a few questions, if I may?

In Green building techniques | Asked By Drew Baden | Dec 28 16
0 Answers

Hydronic radiant heat over concrete slab

I'm building an addition that partly includes an extension for an existing room off one side of my house here in Connecticut. Existing floor is 2 1/4" x 3/4" oak strip hardwood floor. Addition floor will be slab-above-grade with poly and rigid foam underneath the slab. Need to "marry" the existing oak floor (conventional wood subfloor/structure) to new concrete slab using new oak strip flooring. Because I'm building this addition myself, there will be more than sufficient time for the slab to dry (perhaps a year or more) before new finish flooring needs to be installed.

In General questions | Asked By John Rooney | Jan 14 17
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