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16 Answers

Has anyone ever kept sheathing warm and saved labor costs this way?

There are a handful of manufactures who make rigid insulation with OSB bonded to the surface (like a SIP with OSB on one face only. But SIPs are not the topic in this post). This assembly is commonly used for roofing but I was contemplating using it backwards as exterior wall sheathing. By backwards I mean fastening it onto the studs so the OSB is touching the studs and the foam is on the outside. By doing this, the osb is kept warm and that desirable thermal break is incorporated as well (after all thats generally the reason to put rigid on the outer face).

Asked By sean stewart | May 22 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.

Asked By Peter L | May 26 16
5 Answers

Marathon and a heat pump water heater

Planning on Installing a heat pump water heater 80 gal rheem. and dumping it into two marathon water heaters... 50 gallon each. One of the marathons would be right next to the heat pump the other 80 feet away. Big long house.... The one 80 feet away would feed 1 1/2 baths, kitchen sink, dishwasher, washing machine, and potentially outdoor shower...

I know there will be about a gallon and a half sitting in that 3/4 line.. Essentially I am preheating the water going into the marathon...

Here is the question.

Asked By dean sandbo | May 27 16
16 Answers

PEX A vs. PEX B

I am obsessing over which pex to use for a whole house manifold installation. The choices are pex-a (uponor) vs pex b (viega).

Uponor seems easier to work with, less kinking, better flow etc.

What I am most concerned with is:

1.longevity (this is my forever house)
2. safety (leaching of chemicals into drinking water)

I am on a well.

Any input as to the longevity and safety of these two different types of pipes?

Dean

Asked By Dean Sandbo | May 26 16
30 Answers

Improvement on the Lstiburek Ideal Double Stud?

Hi all. Please see the attached PDF of a variation on Joe Lstiburek's Ideal Double Stud Wall design (http://www.greenbuildingadvisor.com/articles/dept/building-science/lstib...).

I am trying to go for something a bit quicker and less labour intensive to build, but that is still very vapour open to the exterior (and occasionally interior) to overcome the usual double stud wall shortcomings.

Please fire away with critiques. The main problems I see are:

Asked By Burke Stoller | May 6 16
6 Answers

How deep do I go? Replacing dormer siding on 1915 house.

Hello- I've been digging into this fantastic treasure trove of articles for a couple of days (and nights) as I plan a re-side project on my dormers (In St. Paul, MN).

The problem is that as I read more, I'm starting to add so much to the "might-as-well" list that it will easily spiral out of control in terms of time and budget.

So- where can I draw the line? What techniques should I use depending on where I draw the line? Here's what I mean:

Asked By Stefan Theimer | May 26 16
9 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.

Asked By Peter Schonherr | May 19 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?

Asked By Dillon Vautrin | May 26 16
8 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.

Asked By Pat Kiernan | May 27 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.

Asked By Andy Nels | Feb 17 16
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