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17 Answers

Re-sealing failing SIP roof panels

We have a 7 year old SIP panel over a timber-frame home. We have noticed for several years significant condensation of moisture to the point of dripping from light fixtures and ceiling fans located in the peaks during hot summer days. Roof is a stone-coated metal shingle panel over Grace Tru-flex underlayment.

Asked By Passagyrs | Jun 19 18
3 Answers

Single minisplit for AC?

Looking for feedback on adding AC to a ~1600 sq ft ranch in central NJ. Current setup is a window unit in the bedroom and a 1980s 220v beast of a wall unit in the dining room. Together they do all right in those worst weeks but for the most part we've just been toughing it out. I'm on a well shaded lot and the house stays reasonably cool during the summer, but also a bit damp. So hoping to dehumidify with the AC and of course cool the place down during the hottest weeks of the year.

Asked By Jeffesonm | Jun 20 18
11 Answers

Air Barrier Location

I'm in the process of beginning our new home in the next few weeks. We're located up in Newfoundland, Canada, just around St. John's. We're planning on incorporating a double stud wall to increase the R-value of the home. The plan is, from outside to in, : R8 Comfortboard, Tyvek, Plywood,, 2x6 wall with fiberglass batt, 6mm poly, and 2x4 wall with fiberglass batt which will contain all of the electrical and plumbing.

Asked By Dan C | Aug 6 17
5 Answers

Carbon monoxide detectors in a fuel-free house?

Just a quick sanity check here. Our house will have no fuel burning devices (also no garage), so code requires only smoke detectors, not combination detectors. Is there any reason at all to have them? The cost difference is fairly small, but if they are completely pointless then I will leave them out. Is there any other possible source of CO?

Asked By Trevor Lambert | Jun 20 18
9 Answers

SCIP, SIP, CMU, ICF?

Hello all.

I am building a house in a hurricane/northeaster prone area of Virginia, and in an area that has potential for flooding to boot.

Keeping in mind that i dont have an unlimited budget, what do you think would be the best long-term, flood resistant, hurricane resistant home?

I love the idea of SCIP, but im not sure i can find skilled shotcrete people and the cost looks prhibitive

I like SIP, but i worry about flooding and hurricane resistance.

Im leaning towards ICF, but thinking it may be cheaper (and maybe "just as good") to just to build CMU with foamboard

Asked By user-7043474 | Jun 20 18
7 Answers

Building code requirements for stacked window headers, bracing, and stucco over foam

We are building in climate zone 5 and the county currently enforces the 2009 IBC & IRC.

We prepared a list of questions for our building inspector, some of which are location specific, but since we have gotten no response we figured some of this is probably common knowledge.

1. Do non-load bearing walls require structural headers?
2. Can vertically stacked windows of the same width share a header and king studs?

Asked By Zane Bridgers | Jun 17 18
2 Answers

Attic open-cell foam: off-gasing / odor

We have a traditional 1966 two story home, dual-zoned home in Atlanta (zone 3A). On April 18th we had our existing inadequate fiberglass insulation removed and open cell foam installed in our 1200 sq ft attic. We have had odor / off-gasing problems since. On cool, cloudy days it’s not very noticeable but on hot, sunny days the odor is quite pronounced and our second floor A/C (handler in the attic) is not usable as it blows in the odor/gases. We’ve been living with open windows and fans upstairs since. The odor is closer to the paint-like I have read about, not the fish-like.

Asked By User-7075353 | May 22 18
9 Answers

Is there any way around putting a heat source in every bedroom?

I was speaking with an HVAC guy in my area today who reminded me that code says we have to have a heat source in every bedroom. We're planning on putting a single head ductless minisplit in our 1450 sf high performance home (to be built next year). Are there other exceptions/solutions out there, or do I just stick a Cadet heater in every bedroom and disconnect them after the inspector checks it off his list?

Asked By Alyssa Hoyt | Feb 4 16
7 Answers

Unorthodox foamless insulation system

I've been a long time reader and spent countless hours on BSC trying to learn all I can on building science. The biggest thing I've learned is how much I didn't know. Long story short...we have been making improvements to our home, some cosmetic and some as efficiency when they align. This winter our dated central air heat pump tried to catch on fire(long strory) and after a few months of research we successfully replaced it with three mini splits and they are fantastic! It was unplanned but extremely successful.

Asked By Russell Boudreau | Jun 19 18
14 Answers

Mortar bridging and droppings

General question on Mortar Bridging and Dropping workmanship.(CZ4)

Here are a few images of some brick veneer on a house. Its not mine, but it is from the builder I will be using. I've read that droppings and bridging are "bad" but I don't know what constitutes good vs typical vs poor. So I've attached some pictures to get others viewpoint on the quality of this work. There is a single layer of tyvek and then OSB behind that, and I'd say ~1" of space behind the veneer, at least where there is not bridging.

Asked By Stephen Cook | Jun 16 18
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