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6 Answers

Heat pump head unit locations

Hello all,

I'm currently building a small house in Vermont and I plan to heat it with mini splits. It's a 1300 square foot 2 bedroom ranch with an unfinished walkout basement. (See attached floor plan image.) The walls are 2x6 with fiberglass in the cavity and 2" of foam on the outside. The below-grade walls in the walkout basement will have 2x4 with fiberglass. The above-grade walls in the walkout will have the same assembly as the main floor.

I'm currently planning to have two outdoor heat pump units, one for the master suite, and one for the living room.

In Mechanicals | Asked By Ross Carlson | Jan 11 17
3 Answers

ERV - did I find a good buy or make a mistake?

My house plan is a simple, 1900 square foot ranch.

I purchased a Broan ERV, model 140 today. I could not turn down the price of $1187.75, shipped, tax-free. I thought this deal was "HUGE", spoken in my best Donald Trump voice.

However, I must admit that I did not do my homework on this unit before making the impulse buy.
I just felt it was a grat price and knew it would do the job per the numbers. So, using the formula here, 7.5 cfm per person plus 3 cfm per 100 square feet , I arrive at (7.5*2)+(3*19) = 72CFM.

In Mechanicals | Asked By Drew Baden | Jan 11 17
2 Answers

What is in solid glue-down cork tile ?

My wife and I are looking to install a glue down solid cork tile in our on-grade basement. Finding it hard to get definite answers. 1. Is there formaldehyde or other chemical used in production? 2. What is a high quality yet natural, low - no VOC oil finish to apply o cork once installed? and 3. What is a long lasting, high quality contact cement for installing over 1 year old slab? Slab is dry and clean with insulation and vapor barrier underneath. We're looking to keep cost of tiles low and have been looking at Jelinek and We cork in unfinished 12" X 12". 4.

In Green products and materials | Asked By Ben Williams | Jan 11 17
1 Answer

Dense-packed cellulose, slab on grade, pole building

Thanks to all who take the time to read this and the responses.

In General questions | Asked By Paul Arens | Jan 11 17
8 Answers

HTP Phoenix Light Duty paired with Lifebreath Clean Air Furnace (downdraft)

I want to replace the atmospheric water heater (interior to my house) with sealed combustion. I also wanted to replace the 80% furnace that sits right beside the WH interior to the house. I learned early from GBA that inside combustion is to be avoided.

Fast forward...I am looking at the HTP Phoenix Light Duty + Lifebreath CAF (downdraft). I am in the Seattle, WA area in a 1950's rambler.

In Mechanicals | Asked By S K | Jan 11 17
7 Answers

Is it possible to insulate piping in a vented attic by "bringing it inside the envelope"?

Hello I have a home that was built by a bunch of meth-heads and their friends apparently. I'm in Zone 4, near STL.

When they ran the PEX from the manifold in the utility room, they just laid all of the tubing on the top of the roof trusses and sprayed insulation over them. For one section that goes to the ice-maker they put a single layer of the foam insulation over this.

Every year since I've moved in all of my water lines except my kitchen sink will freeze if there are sustained temps below about 28 F.

In General questions | Asked By Mike M | Jan 10 17
2 Answers

What kind of fastener should I use to attach 3/8" cement board over rigid insulation on our foundation at grade?

When using rigid insulation on the exterior of a foundation, drawings usually show some kind of cement board covering the rigid insulation at grade.

I'm having trouble finding out what kind of fasteners we should be using to attach it. I can't find any videos, diagrams, or other resources that show this detail.

Does anyone have experience doing this set-up, and if so, what kind of fastener did you use, and were you happy with the results? Does anyone know of online resources I could consult?

Our set-up is 5" of Roxul Comfortboard 80 on the exterior of our foundation.

In Green building techniques | Asked By Eric Whetzel | Jan 10 17
7 Answers

Bentonite on basement walls

I recently bought a house in Marine 4C climate zone that has an east facing daylight basement. The previous owner installed an interior french drain that drains into a sump pump. The drainlines for the downspouts were rerouted from the front(west, which slopes slightly into the house) to the north and south sides. The problems they were trying to resolve have apparently been fixed because the interior concrete walls of the basement are not damp and the sump basin is bone dry after above normal fall and winter rains.

In Energy efficiency and durability | Asked By Jeffrey Stark | Jan 10 17
3 Answers

Best air sealing and insulation for knee walls in tray ceiling


I have a single family home in climate zone 5B.The attic is ventilated. I had the attic air sealed and insulated to R50 with blown in cellulose 1 year ago. It looks like they neglected to do the knee walls properly on the great room which has a tray ceiling which is 3 feet high (see photo). They just wrapped the knee walls with batt insulation and otherwise didn't do anything else.

1. What would be the best options to air seal and insulate the knee walls?
2. Is this difficult to do since the attic now looks like a winter wonderland?

Thank you

In Energy efficiency and durability | Asked By Stan Weinstein | Jan 11 17
8 Answers

Mixed roof insulation methods


We are building a home near Ann Arbor, MI and would like some advice on how to approach a specific portion of our building section.

The majority of the home will have R60 blown in cellulose (blue areas) with Intello Plus underneath. The vaulted (red) area will be R60 closed cell foam. The walls will be EIFS, 2x6 R20 Roxul with 4" EPS exterior foam.

Our concern is the clerestory wall (green and purple).
We will continue the EIFS on the exterior portion of the wall (green), but are a little unsure what to do on the vented ceiling/interior wall (purple) section.

In Plans Review | Asked By Eric Burhop | Jan 11 17
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