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2 Answers

Will I do more harm than good adding unfaced polyiso in my exterior walls?

I am building a two story home trying to balance efficiency and cost. Outside is Hardie board strips that look like natural wood boards. Under the hardy board is TyveK, no additional insulation outside. Could not afford zip guard so we used standard particle board looking sheathing. 2x6 walls 16" on center.

In Energy efficiency and durability | Asked By Mike Shultz | Feb 12 16
5 Answers

Duct manifold for a stand-alone ERV

I'm trying to figure out the best way to install my ERV ductwork. I don't have a forced air system, so each supply or exhaust will have it's own duct. I have seen the typical trunk/branch method, but a manifold system seems easier. Does anyone have experience with building a manifold system for mechanical ventilation? I will have three exhaust ports and four fresh air ports. I've looked at the Zehnder systems and they look pretty slick, but I cannot afford the price. I am leaning toward Thermaflex ducts, which are high quality flexible ducts usually used in commercial applications. Thank you!

In Mechanicals | Asked By Adam Emter | Feb 9 16
5 Answers

Can unvented roof assemblies be insulated with fiberglass if I use rigid foam on the exterior of the sheathing?

I have read the Aug 21st post titled "Can Unvented Roof Assemblies Be Insulated with Fiberglass? http://www.greenbuildingadvisor.com/articles/dept/musings/can-unvented-r... I think the answer is "Yes, but...". And here is the but: You need to add the appropriate thickness of rigid foam to the exterior side of the OSB sheathing. I've read so many different roof profile scenarios...I know I ought to be able to figure this out...but I have a few questions...I'm hoping to get some confirmation of my lessons learned as a rookie here on GBA.

In Green building techniques | Asked By Inger Peters | Feb 10 16
5 Answers

"Green Building" and current (2012) code

Has current code 'caught up' to the point where "green building" today revolves around code compliance, HVAC design and choice of "green" interior materials?

Has "green building" gone mainstream with regards to the building envelope?

In Green building techniques | Asked By Chris M | Feb 12 16
16 Answers

Proper crawl space encapsulation and also radon mitigation questions

Hello, I own a 1968 cape cod style home in East Stroudsburg in the Poconos, PA (region 5). It has a full basement with 7' ceilings and concrete floor with probably little to no crushed stone underneath. At some point, there was a ditch cut out along 2 of the walls, with stone and probably a perforated pipe added, and concrete poured back except for a small channel along the block wall. This leads to a sump pit.

Adjacent to one of these 2 walls is a crawl space entrance where an addition was put in.

In General questions | Asked By Ryan O'Rourke | Jan 26 16
53 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

In GBA Pro help | Asked By Aaron H | Jan 31 16
8 Answers

GSHP and an endless pool

We have slowly been renovating our 115 year old, 2200 sq ft farm house over the past 12 years and live in northern Michigan (climate zone 6). This year we are replacing the 60 year old aluminum siding and roof and upgrading the walls to r30 and the roof to r60. We are also adding a 2425 gal endless pool/spa to the outdoor covered porch. I understand an outdoor pool in northern Michigan probably doesn't fall into the category of green building but it will definitely be fun!

In Mechanicals | Asked By Ryan Knight | Feb 9 16
3 Answers

All steel building venting for home

We have an all steel building that we are turning into a home. It currently has a steel roof with fiberglass insulation with a vapor barrier on the warm side, there is no space between the insulation and tin other than the rib gaps of the exterior tin (the walls are the same setup as well). We are going to frame it with wood studs and add rock wool insulation in between the purlins (and girts for the walls) then put our ceiling/wall covering up which will create a cathedral ceiling. My question is how do we vent the ceiling with this setup?

In Energy efficiency and durability | Asked By Victoria Victoria | Feb 12 16
4 Answers

3" and 4" PVC valves that release water but keep air from entering

Need two of these. Can't find them. I have emergency drains that come from my home appliances to daylight. They're allowing too much air infiltration, because they are open at the daylight ends. They are rarely used but necessary if an inside leak develops.

In Mechanicals | Asked By Andy Nels | Feb 12 16
3 Answers

Do I need to vent soffits in with an unvented roof assembly?

I have large 4 foot exterior soffits. I am spray foaming the inside of the roof, an unvented attic assembly. Do I still need to vent my exterior soffit overhangs? Do I need to worry about the air trapped in that cavity if I do not?

In General questions | Asked By dean sandbo | Feb 11 16
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