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8 Answers

SIP roof issues

Hi Everyone.

I was listening to Mr. Holladay on the FHB podcast and started getting nervous about my SIP roof built 3 years ago.. We live in central Washington and the climate is pretty cold in the winter (mid 20's) and hot in the summer (upper 90's). The humidity levels are low year round. We get about 2-3 of snow on the ground by February. The roof is 1/2:12 pitch and is 64'x32'. The bottom seams of the panels were taped, although the tape didn't seem to stick all that well. The humidity in the house is around 28-32% year round. The ceiling is painted drywall.

Asked By Matt Melton | Feb 17 17
5 Answers

Where to vent the dryer and range hood exhaust?

I am building a house with the dryer and the range located in places where it would be difficult to vent them anywhere other than through the roof or through the vented soffit at the eaves of the house. (It's about a 40 foot run to get to the gable end)

I understand that venting an appliance through vented soffit means that the humid air will likely get sucked up into the attic where you don't want it. However, reducing roof penetrations appeals to me and I am concerned about lint build-up being harder to deal with if the dryer is venting through the roof.

Asked By Timothy Godshall | Feb 17 17
4 Answers

Not enough XPS over roof - should I vent?

I am in the Washington DC area - Zone 4. I just had a 1.5/12 single slope roof framed with 2x8's for a 14x20 new block wall garage. On top of the rafters there is a layer of plywood followed by 2" XPS rigid foam followed by another layer of plywood and then an ice and water shield across the entire roof. This week there will be a standing seam metal roof installed on top.

Asked By Calvin Bouchard | Feb 12 17
1 Answer

I have two specific questions regarding efficient home-run plumbing design

My wife and I are currently working with a local design/builder on a set of plans for a small home in Silver City, NM (4B). The main bathroom, mechanical room and kitchen are all grouped together on the 850 square ft main floor. A second bathroom, located directly above the main bathroom, is planned for the 550 square ft loft. The wall assembly will be 2*6, dense pack cellulose, 1 inch of EPS exterior the sheathing, and fiber-cement siding.

Asked By Aaron Beckworth | Feb 17 17
6 Answers

How do I insulate an already framed concrete wall?

Thanks for the amazing posts. I've learned a lot from this site. Here's the scoop. I live in Wisconsin, Zone 6. New construction and a walkout basement with full, 3/4 and 1/2 concrete walls. Builder had fiberglass and poly over studded wood walls and fiberglass only over concrete walls. We had a wet fall and at the end of it, there was just a mess downstairs. I pulled it all out to dry, and there it sits.

Asked By Scott Thompson | Feb 10 17
33 Answers


While I was on the subject originally regarding adding central air to my gas furnace, someone was talking about humidity levels in the winter and how dry you feel at home.
I just realized and was told that whole house humidifiers only work/operate anyway, when the furnace is actually running. Makes sense.
in my opinion, and having a hydrometer to prove it, whole house humidifiers are a waste of money, period.

Asked By Dave Mac | Feb 15 17
2 Answers

What do you do when you can't find duct leakage issue?

Conducted an audit today on a manufactured home with a rectangular duct board system in the belly. Duct leakage testing resulted in NO reading at 25 pascals. We crawled under the entire home following the trunk lines and found no visible signs of broken or disconnected ducts that could explain such high leakage. Has anyone out there ever ran into a situation like this? If so what did you do?

Asked By Benjamin Barker | Feb 16 17
14 Answers

Kingspan Kooltherm - R-8/in?

Recently got sent a sample and some information on a new 'premium' rigid foam Kingspan is trying to market in the US after making it in Europe for quite a while. A little googling and this appears to be some sort of phenolic foam, maybe. Some of the claims in the literature have me scratching my head:

-R-8/inch. Seems awfully high for rigid foam. They claim this is from an ASTM C 518 test but the rep wouldn't send me the actual report.

Asked By Chris B | Feb 16 17
8 Answers

Mini-Split & Generator vs Wood Stove


I'm about to build a house about 8 miles outside of Brockport, NY (near Rochester). The lot has electricity but no gas. I would like to heat my house off mini-splits, and I'm currently having a Manual J done to determine feasibility. The footprint of the house almost guarantees that I will need more than one small mini-split rather than one central unit. I plan on having a backup generator.

Here's the question: Should I put in a wood stove for backup heat, or simply put a small minisplit on the generator?

Asked By John Ranson | Feb 17 17
0 Answers

Do pellet stoves generate much creosote?

Having lived in a house with wood heat for over 40 years, I've fairly familiar with the ways in which wood stoves can contribute to creosote formation in chimneys and stovepipes. However, I'm not very familiar with pellet stoves.

A friend recently wondered about creosote formation in a chimney connected to a pellet stove. So I'd like to hear from owners of pellet stoves: Does your stove lead to more or less creosote formation than a typical wood stove?

-- Martin Holladay

Asked By Martin Holladay | Feb 17 17
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