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11 Answers

Windows -- Pretty Good or better in Western Colorado

I am looking for windows for a Pretty Good house I am preparing to build in Carbondale, CO at an elevation of about 6,200 feet. Climate zone is 6B. We get lots of sun here and large diurnal temperature swings, year round. I don't know of any homes in town with air conditioning. I'm looking at Pretty Good insulation levels, R-5-10-20-40-60 and about 6 to 8% south facing glass with fairly low thermal mass -- partial tile floors and 5/8 drywall. Windows on the north and west will be limited. I've heard that 4% overall operable glass is a reasonable target.

In Energy efficiency and durability | Asked By Pat Kiernan | May 27 16
10 Answers

Sun Pump solar heat pump

Does anyone have experience with the Sun Pump solar heat pump, either with the product itself or dealing with the company? It's a relatively new company located in Vancouver BC.

In Mechanicals | Asked By Peter Schonherr | May 19 16
16 Answers

How to vent a flat roof

Designing a home in Santa Fe, NM. Roof will be TPO over open web trusses. Pitch is 1/4" / ft.
Parapets all around. Insulation will be blown-in cellulose. R value to be 50. How do I vent the roof cavity above the insulation? I could use mushroom caps. I've done the calculations and I need quite a few. How much air space is required above the insulation? 2", 3" or more? Also planning on installing a radiant barrier between the tops of the trusses and the sheathing. When I build crickets over the sheathing will I need to provide air ventilation for the cavity? Thanks!

In General questions | Asked By jack robinson | May 14 16
8 Answers

Fake dormers in 2016

I see these "green energy builders" putting on tacky fake dormers on the roofs of these homes. Usually 2 fake dormers. Are not fake dormers HUGE energy pigs? Not to mention, always a potential source of roof leaks?

I don't get it why they put those tacky things on homes in 2016.

In Energy efficiency and durability | Asked By Peter L | May 26 16
6 Answers

Tremco acoustical sealant vs. Tremco TREMPRO JS-773

Does anyone know the difference between the two? I know the Tremco accoustical sealant is the black death that is known to have properties which make it good for air sealing. The Tremco TREMPRO JS-773 is quite a bit cheaper and is described to be non-skinning and non drying like the acoustical sealant, but I don't really hear of anyone using it. The TREMPRO JS-773 also seems more readily available online. Would the TREMPRO JS-773 be suitable for sealing the sill plate if used in conjunction with an EPDM gasket?

In Green products and materials | Asked By Dillon Vautrin | May 26 16
13 Answers

Adding connected sun room and greenhouse, suggested plans?

I'm thinking of taking this concept and adapting to my situation.

Differences:
Mine can be 15' wide, connected to the house by addition's north wall. Needs to be at least 25' long, up to max 35'.

North wall of addition would join the house, and the long dimension will go south. The sides face east-west.

I plan to add the wall so I can pack it with insulation and make it sturdy for heavy snow years.

In Green building techniques | Asked By Andy Nels | Feb 17 16
19 Answers

Poly vapor barrier under XPS foam board in slab radiant pour

I am building a 28x40 garage in New Hampshire. I am doing an I slab radiant pour. I plan to use 2 inch xps foam board under the slab and as a thermal break to to frost walls. The issue that I have is that this install is for a garage build and will not have a roof over the floor before the slab pour leading to the possibility of rain water ending up being caught between the vapor barrier and foam board before the pour. My question is why would taping the xps foam board seams not act as an effective vapor barrier?

In Energy efficiency and durability | Asked By Jonathan Sinclair | May 26 16
21 Answers

HVAC - Gas furnace vs. heat pump vs. ducted minisplit

It seems the general consensus here, on a very tight or "pretty good" house, is for ductless minisplit. I'm trying to understand the economics.

The following parameters are non-negotiable:
1. Climate zone 3A
2. The house will be piped for natural gas for, at a minimum, cooking and outside grill

In Energy efficiency and durability | Asked By C L | May 22 16
10 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

In GBA Pro help | Asked By Ryan Lambert | Mar 19 16
1 Answer

Paintable low VOC window caulk

Hi,

I am looking for suggestions for a paintable, low VOC interior window caulk for the sealed unit to window stop.

I live in the Vancouver, BC area.

Thanks.

In Green products and materials | Asked By Aaron Gatzke | May 26 16
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