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7 Answers

Leaky Ductwork in Basement

After getting a very poorly rated energy audit from our electric company, I'm working diligently to get our house more air tight. Seeing lots of posts about HVAC equipment, I'm thinking ours is a little lacking. It is 5 years old, the furnace is 95% efficient. But, the black tape is falling off and according to infrared, it is leaking. I've attached several pictures and also infrared pictures. We are in zone 5 (NW MO). It is 20 degrees outside and our basement walls are 47 and 53 at the frost line.

Asked By Becky Parrish | Feb 9 16
2 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...

Asked By Trevor Fontaine | Feb 9 16
1 Answer

Best brand of screws with washers for steel roofing

The painted steel roofing panels on my simple 4:12 gable roof will be attached to 2x4 strapping with exposed fasteners. The #9 x 1-1/2" screws with EPDM washers used to secure the roofing to the wood range from around 12 cents each made by Metal Sales, who make lots of steel roofing such as ClassicRib, to a not-yet-specified brand that are 8 cents each. The Metal Sales screws are described as having "Metal encapsulated in EPDM for extra strength." How significant are the differences between the brands of these screws, and which do you recommend?

Asked By Jeff Cooper | Feb 9 16
0 Answers

Duct Manifold for Standalone 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!

Asked By Adam Emter | Feb 9 16
3 Answers

Another “rigid-foam attached to the underside of rafters” plan

This is new construction with an all hip roof with a very short ridge located in the northern part of zone 3. I’ve ended up with a large cathedral ceiling area which opens to additional living space tucked under the roof resulting in an unvented attic. Is my insulation plan workable? Might I have future water issues? Will my stack-up breathe and dry sufficiently? What issues will the trades find with the plan? is there a better plan?

Asked By Richard | Dec 28 15
2 Answers

Appropriate treatment of shower/tub walls adjacent to dense pack cellulose?

Climate zone 4C marine, planning for new construction.

Planned typical R-26 exterior wall section: fiber cement siding, 1X rainscreen furring, 3" 8pcf rock wool, taped sheathing (primary air control and WRB), 2X4 load-bearing wall with 3.5pcf cellulose, 1/2" gypsum board.

How should interior high-humidity areas like showers adjacent to this exterior wall section be handled?

Asked By Stuart Friedberg | Feb 9 16
33 Answers

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

Asked By Carolyn Farrow | Feb 8 16
2 Answers

A couple of renovation questions regarding my 1960 Cape

Hello all, I was looking up information on housewrap, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to go about doing some renovations this spring/summer on my house

Asked By Khouri Rice | Feb 9 16
28 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.

Asked By Aaron H | Jan 31 16
1 Answer

Do they sell Dow Thermax anymore?

I have a big basement I need to insulate from the interior and I'd like to avoid the cost of framing and drywall since the basement will only be used for storage.

Do they still make Dow Thermax? I can't seem to find it anywhere. Is there a new product that meets the fire ratings as Thermax, that won't require drywall over it?

Asked By Clay Whitenack | Feb 9 16
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