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1 Answer

What is best way to insulate our new home?

After reading several of the articles on insulation of walls and vaulted ceilings lately, I am a bit confused. We live in SW Montana. Part of the home includes a vaulted ceiling in the great room, the rest of the ceilings are standard 8' heights. The plan calls for 2x8 rafters in the great room. My plan was to 6" bats in the ceiling, then cover with closed cell rigid board (up to 2 ") then gyp rock to achieve a decent R value. Likewise, the walls are 2x6 so planned on batts with closed cell on outside and then installing cedar board/batten.

In Energy efficiency and durability | Asked By richard fasching | Dec 17 14
38 Answers

Heating with modulating condensing units

So far my looking into the use of a modulating condensing unit has left me with
the following;

They are high tech
They cost more than some older tech
They need good water with proper hardness and PH
They need a tech that is trained to maintain them
They do not condense if the return water is above 125 degrees.
Many install set ups include primary, secondary and what I call tertiary loops which to me add cost.

I can't understand how we go from $1000 to heat water to $8000 for all the parts for a fairly basic

In Mechanicals | Asked By aj builder, Upstate NY Zone 6a | Dec 15 14
1 Answer

Wet OSB - how much water can it take?

We are two weeks from having trusses and roof on our new house. The rains are killing us. We painted the subfloors before the rains and have been sucking water after each storm. We are dreading putting the hardwood floors down (someday). How much damage can happen due to this rain, glad it's helping the drought, but it's definitely stressing us out!

In General questions | Asked By colleen1 runyen | Dec 17 14
7 Answers

Flow control valves for radiant floor heating

I have high efficiency house in central Vermont. It has radiant tubing in the floor for heat. I am trying to get the on demand hot water heater, a Takagi, and the circulator pumps to run as little as possible. Electricity is the biggest obstacle. The house is off grid with PV and batteries. Both are a little on the small side. The house has 6 zones with flow valves on each. No zone is over 400 feet. Tubing is 1/2 inch PEX. Current Delta T when three or more zones are open is 10 degrees. I currently have all flow valves wide open.

In Mechanicals | Asked By Jon Olson | Dec 16 14
6 Answers

Rigid insulation

Builder put rigid insulation on the exterior of the house.
But it is not sealed! Should they have put metal flashing on first?
Picture is looking up foundation wall, insulation, siding.

.

In General questions | Asked By Shawn Ward | Dec 16 14
6 Answers

Has GBA ever tested polyester fiber insulation made from clothing?

Has GBA ever tested polyester fiber insulation made from clothing? If so, what were the results and who makes it in North America?

Apparently, there is a huge push to use PET from recycled plastic bottles but little push to use recycled poly fabric. Some 75 to 80 % of Pet is used in fabric and it is largely going to landfills.

In General questions | Asked By Brian Timlick | Dec 16 14
4 Answers

Is Advantech better than plywood for subflooring?

My block and beam 1940's house had original tongue and groove 3/4 " pinewood floors in the original rooms of the house. This was the only floor. I've been checking around, and the best advice I've received is to use 3/4 Advantech over the original floors, before laying new 3/4" hardwoods. I believe this to be good advice, but is Advantech needed over regular plywood? And is 3/4" plywood needed over 1/2" plywood?

Thanks for any input.
NM

In Energy efficiency and durability | Asked By N Madrid | Dec 15 14
2 Answers

Is Roxul or EPS more environmentally friendly overall?

I certainly like that Roxul has high recycled content, but this PDF published by Roxul makes it look like EPS actually has a lower Lifetime GWP / sq. ft x R. Wouldn't that make it a better choice in the long run?

http://www.roxul.com/files/RX-NA_EN/pdf/Brochures%20and%20Sell%20Sheets/...

The document shows Roxul = 0.0455 and EPS = 0.036.
In addition they are comparing to a 1 pound EPS that only has R3.9 per inch.
If I am using Foam Control 2 pound Type IX the R value is listed at 4.35 per inch (75 degrees F.)
Would that be an even lower Lifetime GWP?

In Green products and materials | Asked By Marc Sloot | Dec 12 14
2 Answers

Cost analysis of thermal bridging in zone 2

Adding an addition to the house. 2x6 at 24". About 60 feet of wall. Cedar shingle siding. Concerned about the cost of installing ridged foam to prevent thermal bridging. Will the energy cost savings ever provide a return on the additional foam, horizontal battens at 5", labor, etc.

In Energy efficiency and durability | Asked By Robert Brown | Dec 15 14
14 Answers

Flat roof insulation

I have built an extension to my house with flat roof, continuation of the existing house. The rafters are 16 in apart and there is 6 in left for the insulation under the sheeting. The plans are requiring R30 insulation and the building inspector requested hard foam Thermasheath- 3, 5 in thick, leaving 1 in for breathing. The drywall was not installed yet, when water from condensation came down all over the place. There are vents on both sides of the roof, in each bay under the insulation level, not allowing the hot air to escape.

In Energy efficiency and durability | Asked By Angela M | Nov 22 13
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