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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
1 Answer

WRB questions on a remodel


I recently asked for some tips regarding my proposed roof assembly for a remodel of a ca. 1830 farmhouse in northern New York, zone 6. I am now looking for some feedback on the wall assembly. I plan to re-sheathe the house with zip wall sheathing. Mostly I am doing this because at some point the wind bracing was cut out of the frame of this timber framed home- don't ask me why?!
After the zip wall is on and taped I plan to add 5.5" of recycled polyiso and then install a 1x4 rain screen followed by cedar clapboard siding.

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

What is the best material for an air barrier?

Before I can ask my question, I should explain exactly how we'll be using the material.
I"m in Zone 5 (Massachusetts).

In Green products and materials | Asked By Bill L | Jul 18 13
4 Answers

Is it prudent to apply exterior foam insulation on a SIP wall to minimize thermal bridging?

I am building a home in northern Indiana with SIP walls on an ICF foundation. To minimize thermal bridging I was wondering if there is a downside to adding 1" exterior foam before applying fiber cement cladding?

In Energy efficiency and durability | Asked By Sarah Oudman | Jul 8 13
4 Answers

Tips for rigid foam installation

I'm retrofitting a 1960's ranch house with two layers of 2" foil faced polyiso rigid foam. I have a few questions about the detailing:

- what is the minimum amount of seam staggering recommended between the two layers of foam?
- since neither the insulation sheets nor the house is perfectly square, what amount of gap between sheets is acceptable to simply tape over?
- for larger gaps would you suggest filling them with regular spray foam in a can or use the low expansion stuff?

In Green building techniques | Asked By Lesley Frana | Jul 22 13
6 Answers

Vapor-open insulation systems?

We have are trying to insulate a historic masonry townhouse and extererior insulation is not an option.

In PassivHaus | Asked By Daniel Herskowitz | Jul 13 13
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