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5 Answers

Plywood clips in new home construction

We are finally building the house that I have been planning for the past 3 years.

We started with framing from a Shelter kit because I had the naive notion that my brother and I could frame the house. Fortunately I have a very good contractor and carpenters who have been doing the framing. I go by everyday and make sure that all the seams are sealed well.

We are now putting on the roof sheathing to try to protect the framing from the record-breaking July rain in the Southeast (most ever in recorded).

In Energy efficiency and durability | Asked By Lucy Foxworth | Jul 29 13
12 Answers

Tight home — help with indoor humidity

Some basic background: Finishing the new home build. Zone 6 (Iowa). Currently hot, humid days. About 90-95 outside with 80%+ humidity levels.

House is 3800 sqft, (half main level, rest is basement, fully ducted and conditioned however) r28 full ICF with R60 blown attic with spray foam attic seal, triple pane windows. Heating is through a ducted furnace (Lennox SLP98) and an XP16 air conditioner. HRV for the home.

In Mechanicals | Asked By Jesse Lizer | Jul 22 13
40 Answers

Minisplit comfort

Is using a single mini split to heat and cool my "dream house" going to result in acceptably even temperature distribution? The house will be well enough insulated with r60 ceiling, r40 walls, r30 basement and r24 below slab and well sealed (under 1 ACH goal) with great fiberglass triple pane windows that barely crack r5. I've attached the tentative floor plan to illustrate my concern. Though a mini split will be sufficient heat/cooling power the temperature difference in the distant bedroom vs the main living areas is asking for trouble, I believe.

In Energy efficiency and durability | Asked By Jerry Liebler | Jul 19 13
6 Answers

Formula for R-Value?

This is probably a really stupid question, but is there a way to calculate the temperature of air after it has passed through insulation?

For instance, if it is 20 degrees outside, and I have a R-30 wall, what would be the temperature of the air that is on the other side of the insulation?

In General questions | Asked By J S | Jul 20 13
7 Answers

Sewer smell

So in the summer only we have what can be a strong sewer smell in the unfinished part of the basement. What I don't understand is the smell is only present in the summer time, not the winter. Following the smell I believe I have located the source which is under a shower in a bathroom that was renovated before we moved into the home. Everything is dry around the plumbing, but am wondering if it could possibly be coming from the flexible T fitting where the new PVC drain line and old copper drain line connect. Has anyone had experiences with these connections not working well.

In General questions | Asked By Joshua Lloyd | Jul 20 13
5 Answers

Combustion air in a very tight house

I am planning to heat with two mini splits in a 1200 sq. foot storey and a half ...total sq. ft of 2100 .My back up will be a 20,000 btu propane free standing fireplace It will be a tight house ..Will air leakage supply the fresh air for combustion or do I need a dedicated fresh air supply ...I will have an HRV ...thanks,Bob

In General questions | Asked By bob holodinsky | Jul 26 13
5 Answers

Insect chemicals in a green house

Our cat has fleas and the vet said we need to "bomb" the house to prevent an infestation. Our house is tight (745 CFM50) and IAQ compatible (we followed the checklist but didn't pursue certification) so the last thing I want is to spray a bunch of chemicals inside. Considering the house, are there any good options to eliminate the fleas?

In Green products and materials | Asked By Chris Baddorf | Jul 23 13
4 Answers

Repairing hydronic floor heat leak in concrete

I have a 1953 home with hydronic floor heating that was abandoned in 2006 due to leakage. I have been looking for a product that may help and I think I have finally found one but can not find anyone with experience in the English-speaking world to help....

The system is iron pipe (or maybe mild steel) in concrete floor slab-on-grade construction with two zones. I have removed the furnace and pumps to make room in the utility room but would love to revive the system if possible.

In Mechanicals | Asked By Josh Wimpey | Jul 24 13
7 Answers

Roof assembly tips

I'm currently remodeling a ca. 1830 farmhouse in Northern New York. Zone 6. I'm looking for some tips on the roof assembly. I am planning on adding 8.5" of recycled polyiso to the roof, this will be the only insulation- none will be added on the interior. I was planning to through screw zip sheathing over the foam and then install a standing seam metal roof. This is going to be an unvented assembly on a very simple gable roof- no dormers, bump-outs, skylights, etc.

In Green building techniques | Asked By Michael Intrabartola | Jul 25 13
13 Answers

Sorting through the Liquid Applied Weather Barriers

After a productive discussion on Weather Resistive Barriers behind a masonry wall, I am starting this new thread in hopes of hearing people's experience and opinion about the newfangled Liquid Applied Weather Resistive Barriers (LAWBs). In the raging debate about housewraps and tapes and claddings, the LAWB solution seems to overcome some of the inherent problems.

Martin has already written on the topic: http://www.greenbuildingadvisor.com/node/17000

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Jun 28 13
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