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16 Answers

Insulating an attic furnace room

I have a furnace in my attic around which the builder constructed an enclosure from 2X4 and foil-backed fiberglass insulation. I've been told the R-value of the insulation should be sufficient, but there is clearly air getting through at the seams and creating hot spots in the attic which then leads to ice dams etc. What is proper protocol for insulating these attic "furnace rooms"?

In General questions | Asked By Patrick Finn | Oct 15 14
4 Answers

German flangeless window install and flashing details

I have an upcoming job with German tilt turn windows, they don't come with flanges like US windows typically do. My install plan is to screw through the frame (unless someone has a better idea) and once installed I am not that concerned about getting them air sealed. What I am trying to figure out is what is the best way to integrate them with the WRB and make sure they are not going to allow water into the home? Anybody know of a manufacturer who publishes good instructions for this? Maybe a German site that shows the materials and steps? This particular manufacturer does not.

In Green building techniques | Asked By Bob C | Feb 12 16
6 Answers

Does anyone have experience with Zehnder ComfoFlex?

We are building a new house and in the final stages of design. The design includes an HRV and Zehnder ComfoTube looked great until I discovered that it is not UL listed. So, I'm curious if anyone can provide feedback on ComfoFlex. There isn't much on the intertubes...

In Mechanicals | Asked By Trevor Fontaine | Feb 9 16
2 Answers

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

Hello:
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
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