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11 Answers

ICF Cape Cod design worries: the roof deck nightmare

Last summer/fall my wife and I started designing a retirement home and after posting my worries on moisture to this blog, I received some great advice that gave much “cause for pause” to study more and also to provide the more detail members needed to better understand the design and what I was trying to accomplish. Since then, and as members of both GreenBuildingAdvisor.com and FineHomeBuilding.com, I’ve studied everything I could get my hands for 9-months from these two websites to help me with my Zone 4 Potomac River/Chesapeake Bay region home.

In Energy efficiency and durability | Asked By Eric Kessler | Jun 16 14
4 Answers

I think I have a foil bubble "insulation" nightmare in the making?

From inside to outside of my wall- sheetrock, foil bubble, studs, foil bubble, plywood, typar, cedar shingles. I am watching my husband (under the direction of my uncle who has worked in construction for 40 years) build my house and I am really concerned that this is not good. We live in Maine, so it gets pretty cold. Also, I was told by another carpenter that this could possibly rot the frame? Am I panicking over nothing or is this going to be a disaster?

In General questions | Asked By casey dragon | Jun 21 14
3 Answers

Metal roof: pros and cons of going white

My shingles need to be replaced and I'm having a standing seam roof installed. Buy once cry once... Anyway, I'm a little bit torn on the color. Aesthetically, I'm pretty flexible, since I'm also having the stucco re-done soon and will be able to color it whatever will look good with the roof. I live in zone 5b in New Mexico. We need more heating than cooling, but the summer heat can be pretty unbearable. I use evaporative cooling due to the low humidity so my cooling bills are fairly low.

In Green products and materials | Asked By Nathaniel G | Jun 21 14
3 Answers

Stucco and air gap question with Home Slicker

I am remodeling my house down to the studs. Put In cellulose insulation and OSB - 2x4 walls. Going with stucco on bottom half. I read that this is a dangerous combo without an airgap. So I forked out the bucks and bought Home Slicker stone and stucco to create a 1/4 inch air gap. We have installed standard Tyvek and have the Home Slicker Stone and Stucco over it. So my big question is do we need another layer of felt on the outside of Home Slicker or is the layer of stucco blocking fabric that comes attached to Home Slicker good enough?

In General questions | Asked By joel kauffman | Jun 22 14
2 Answers

What clear finish is best for wood cabinets and protecting indoor air quality?

We are working very hard to get green cabinets from a custom woodworker. Air quality is our primary concern. We are confused about what type of finish should go on these cabinets--the cabinet fronts will be solid wood (walnut and oak).

In GBA Pro help | Asked By Mindy Munger | Jun 22 14
3 Answers

Ventilation through HVAC air return

My house has no ventilation aside from the bath and kitchen exhausts. This needs to change. ASHRAE 62.2 wants me to have 66cfm, and BSC-01 42cfm. No way I'm getting that through the cracks of the windows. But I don't want a whole 'nother duct system. I already have ducts! Also, I don't like the idea of exhaust-only. Where's that air gonna come from? My crawlspace is icky!

In Plans Review | Asked By Jacob Weel | Jun 21 14
3 Answers

Air barrier continuity

I am working on total renovation of a 1950's ranch with a basement that walks out to grade. The roof and framed wall assemblies described below describe how the home will be renovated.

1) Roof assembly: 2x10 rafters, 1x4 board sheathing, peel-and-stick waterproof membrane, 8" reclaimed polyiso ((4) 2" layers), OSB, tar paper, standing seam metal roof
2)Exterior framed wall section: 2x4, OSB, tyvek drain wrap, (2) 2" reclaimed polyiso, 1x4 rainscreen, wood siding
3) Exterior CMU walls: 2x4 framed wall, 2" reclaimed polyiso, drainage mat, CMU, parging

In Energy efficiency and durability | Asked By Charles Chiampou | Jun 21 14
1 Answer

I live in a two story townhome with 2,000 sq. ft. and one heating system

I live in a two story townhome with 2,000 sq. ft. and one heating system. The temperatures are always uneven from one floor to another. Should it take two separate HVAC systems to even out temps? Looking for suggestions.The present system is 80% natural gas furnace and builder AC.

In Mechanicals | Asked By James Brown | Jun 21 14
11 Answers

TwinFresh Comfo 32 CFM Power 5 in. Single-Room Energy Recovery Ventilator

I just took ownership of the first HRV to be sold at Home Depot. I love it.

Price $475

Extra stuff I learned about it:

1. The 16cfm mode (perfect for a 2 person bedroom) is only 0.3 sones at 4 watts. Almost inaudible.

2. Low speed is 8cfm (the one person setting) is 0.1 sones which is TOTALLY inaudible.

3. It can cycle on humidity if desired. That is, it will come on when the humidity reaches 40%RH (low), 50% (medium), or 60% (high). When the humidity drops below the setpoint, it shuts off.

In Mechanicals | Asked By Kevin Dickson, MSME | Jun 6 14
6 Answers

Canned foam not airtight?

Is there more information regarding whether canned one part foam is airtight? Is there a study done on this? I believe it was mentioned in the cut n cobble blog. Is one brand better than another? Is window and door low expansion better than crack and gap/fireblock? I currently use the Great Stuff Pro brand due its the easiest to get at the big box stores. Any info would be appreciated!

In General questions | Asked By eric nutis | Dec 6 13
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