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3 Answers

Applying Stucco to Rigid Foam over CMUs

I am planning on exposing my earth-bermed house on the west side. We live in Ithaca, NY. Zone 5, sometimes 6. Unfortunately, the house was built 30 yrs ago as a rectangle, North to South. The short side is facing South. We only have windows on our short south side, so we are exposing the CMU blocks on the west to introduce some windows.

I am going to add 3" of rigid foam over the vapor barrier that will go over the CMUs. Then, 2 layers of building paper, the lath, then stucco.

In Energy efficiency and durability | Asked By Rick Ryan | Apr 4 13
10 Answers

Are lightweight thermal mass systems effective?

We have an on-going discussion about Thermal Mass Systems that is getting nowhere. Heavy-weight mass walls and floors are easy for all to understand, like concrete, rock, adobe, rammed earth, water, etc.; however the issues we have is with Light-weight mass like some ICFs and CIPs. How can an INSULATED product be an efficient thermal mass system at the same time? If the insulation is preventing the concrete core to get any heat/cold, how can that provide good thermal mass results. Also with products like AAC, if they are insulated CIPs, how can they be good thermal mass products?

In General questions | Asked By Armando Cobo | Apr 1 13
5 Answers

Firestone polyiso insulation

I think I would like to use 3 1/4" Polyisocyanurate in the 2x4 exterior wall stud cavities in a bathroom. As far as I know Firestone is the only company currently producing such a thick piece. This product is intended for roofing applications. This would provide a LTTR of 20.1. Much better than I could get with Roxul or fiberglass. I'm not sure what problems might arise from using this product. I think the main worry would be a moisture issue of one type or another. As a second choice several layers of the DOW Tuff R could perform the same function.

In General questions | Asked By Donald Fletcher | Apr 3 13
0 Answers

Flashing a Euro window sill

Gutmann and a number of other German companies make an aluminum sill w/ end caps designed for use w/ Euro tilt turn windows. Have you seen any flashing details for installation of a Euro sill in a wood frame structure w/ rigid insulation, rain screen and siding?
Tom N.

In Green building techniques | Asked By Thomas Nedelsky | Apr 4 13
10 Answers

Keep my old exterior walls dry

Hi Martin I live in New Brunswick, Canada in an approximately 100 year old house. As I am renovating room by room Id like to know how to properly insure my exterior walls stay dry. Ive poured through your blogs and forums and would like to know if my idea is solid.

In Energy efficiency and durability | Asked By Chris McLean | Apr 3 13
2 Answers

Should I seal my crawl space vents?

I recently finished a single-room addition on our house. It sits on top of a 4' block wall crawl space, the floor of which is at grade on one end and about 18" below grade at the other end. I put down 6 mil poly which runs up the wall about a foot and then is sealed to the concrete block. I insulated the underside of the addition floor with R-30 batts. I also put in some foundation vents around the perimeter, spaced about every 15 feet.

In General questions | Asked By Timothy Godshall | Apr 3 13
2 Answers

Location of jumper duct

We are building a new home in southwest Florida. The HVAC ductwork has been installed. A return air jumper duct is located in the ceiling from the hallway outside the master bedroom to the ceiling on the inside of the master bedroom. One of the bedroom supply vents is located right next to the jumper duct (within a couple of inches). Is this okay or should the supply vent be moved a few feet away? An easy fix now before the drywall goes up.

In Mechanicals | Asked By Fred Clarke | Apr 3 13
0 Answers

Worcester MA Deep Energy Retrofit open house

This coming Saturday ( 6 April 2013, between 10AM-2PM) there will be an open house on a recently completed Deep Energy Retrofit (DER) on a 3-family I had an advisory role in. It's located at 29 Crompton Street, Worcester, MA. (Fairly easy access from I-290.)

Apparently the US Congressman Jim McGovern will be doing a drive-by presentation on it too. See the attached announcement sheet from National Grid (the subsidizing utility that helped make the DER affordable to the energy-ambitious landlord/owner.)

In General questions | Asked By Dana Dorsett | Apr 3 13
0 Answers

Quality exterior, eco-friendly spray primer for wood?

I am not having much luck finding an environmentally friendly (I use the term loosely) spray primer for wood. We are using it for end grain cuts for trim and siding, and occasionally for shorter (6' and under) edge grain rips. We have been using Krylon's Eco-Guard for years, which is the nicest product we have found to date. It has shown no signs of joint or paint failure after 5 years of Maine coastal/island abuse. The major downside to the Eco-Guard is the spray tip, it clogs fairly easily (even after inverting and spraying), and tends to spray "blobs" of primer.

In Green products and materials | Asked By Heather Thompson | Apr 3 13
93 Answers

Explain the correct usage of rigid insulation on the exterior of the building.

Rigid insulation seems like a good choice to add R-value to the whole wall (breaking the thermal bridging, etc) as opposed to just between the studs like most insulation. But isn't it basically impermeable and thus not allowing the wall to breath...not allowing moisture from the inside to exit by diffusion.

In Energy efficiency and durability | Asked By Conrad Welch | Nov 3 09
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