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6 Answers

Ants in your exterior foam?

Been working on a build over the past few years. It's a cape style home in zone 6. I've insulated the floor of the top floor and walls below for now because I can't afford to finish and heat the top floor. I have not heated the house yet. I'm seeing small winged ants crawling out of my north window in the top floor. The wall has exterior 2in foil faced tuff r polyiso taped with strapping and vinyl siding over it. I've recently sprayed the area with boric acid. Short of ripping the foam off the house, what else can I do?

In General questions | Asked By stephen edge | Sep 5 14
14 Answers

Using an "Arctic wall" design for a cathedral ceiling in Climate Zone 6

Wondering if the arctic wall design would be appropriate to use as a roof/cathedral ceiling here in CZ6 upstate NY. There is a comment about it on Martin's blog, but I didn't see any discussion : http://www.greenbuildingadvisor.com/blogs/dept/musings/how-build-insulat...

from inside out it would be:
2x4 service cavity,
1/2" CDX taped and sealed,
parallel chord trusses 12-12 pitch dense packed with cellulose,
vapor open WRB (suggestions for best product welcome),
2x4 furring,
5/8 sheathing,
asphalt shingles.

In Green building techniques | Asked By Trevor Chadwick | Sep 1 14
28 Answers

2x4 wall buildups with polyiso/air barriers/vapor retarders

Hi all,
I am building a 16x40 / 2 storey residential addition in climate zone 7 (Columbia Valley, BC Canada)
My wall section that I am currently specing is as such:
1/2" GWB
2x4 framing, c/w roxul R14 batt insulation
1/2" plywood sheathing
1-1/2" polyiso
3/4" rain strapping
Wood siding.

My question is mostly concerned with the right polyiso product to use and how this will affect whether or not we have to install an interior vapor retarder, and if so which class - 1, 2 or 3?

In Energy efficiency and durability | Asked By jeremy harris | Sep 3 14
5 Answers

Should I go with a ground-source heat pump or PV-powered electric boiler?

I have a 1940's Cape Cod (1200Sq Ft) along the shoreline in Connecticut (Last bill was 294KWH cost $64.09). I want to ditch oil and swap to a new boiler for my hot water cast iron radiators. The overall plan is to add a functional 2nd floor and become a colonial style home, and make vast improvements to the insulation, windows, and air sealing in that process. I'll be demolishing the chimney as a part of adding on the second floor so I need to get a good heating plan in place before I start executing the building/insulation/windows plan rolling.

In Mechanicals | Asked By Kevin Dingle | Sep 5 14
2 Answers

Additional considerations for finishing a walk-out basement to be a pottery studio?

I was asked recently to give some advise to to some friends on how best to insulate/finish the walk out basement of their two story home in Waitsfield, Vermont. The basement will be used as a pottery studio (read high moisture).

The home has radiant baseboard heat in the basement and the main level as well as a wood stove on the main level. The main level/2nd floor will also have an HRV.

The basement walls will be 2.5 inches of polyiso against the foundation with a finished wall on the inside, possibly with blown cellulose.

In Energy efficiency and durability | Asked By Cyrus Collins | Sep 4 14
32 Answers

HRV with bathroom exhaust fan

I asked this question in the comments of an article, but thought I would have more luck here...

I am installing a LifeBreath 155ECM HRV in a new home. It will be exhausting air from 3 bathrooms spread across 2 stories. The HVAC sub is recommending installing separate bathroom exhaust fans for local exhaust (shower moisture, odor, etc.).

In Mechanicals | Asked By Chris Harris | Sep 20 10
10 Answers

Permeability of ASTM D 3909 cap sheet; needing roof to dry to outside

4" of 2 lb closed cell spray foam will go on underside of roof sheathing....so roof needs to dry to outside; hence why I am using #30 felt/tar paper instead of a non-permeable ice & water shield.

However, to get my Class A fire rated system, I need to use an ASTM D 3909 cap sheet over the tar paper. How well is this system going to be able to dry to the outside and will there be any issues with this system?

The roofing material is a synthetic shake; Bellaforte by DaVinci.


In General questions | Asked By eric Mikkelsen | Aug 29 14
6 Answers

Measuring moisture coming thru basement slab


My 2150 SFT ranch home with ICF walls and a full basement has NO vapor barrier (polyethylene layer) under the slab. Just pea gravel surrounded by drain pipes that exhaust into a lake behind the home. Currently I am running a stand-alone dehumidifier continuously and this is keeping the basement at about 35-40% RH. I also have a radon SSD fan installed a few weeks back. The fan is a RadonAway RP140 that uses 14W and is energy star rated.

In GBA Pro help | Asked By Venkat Y | Sep 3 14
3 Answers

EPS / XPS on interior ceiling

Problem: I have a very inefficient home in Southern California that was built in the late '70's with an exposed, pitched ceiling that slopes from 7' all the way up to about 16'. Even with a brand new air conditioning unit, the home is stifling hot with the 90+ degree weather we've had lately; and my AC unit never shuts off.

In Energy efficiency and durability | Asked By Michael Berger | Sep 3 14
33 Answers

Ready to insulate a new home

I am ready to insulate a new home, and need to make a final decision. I need help.
I have been the recipient of many helpful tips and guidance from thes pages as well as other green forums and it's all kind of coming to a head in our new home build as I attempt to make a decision about the insulation we will use. Here is the specs on my houses wall stack up

LOCATION: 47460 On the line of upper climate zone 4 and lower 5

2x6 exterior walls, 1/2 inch sheathing with tyvek, 1.5" polyiso foam with taped seams, vinyl siding

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 8 14
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