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6 Answers

How to insulate a curved 0.25-inch-thick zero-perm wall (a.k.a. a "boat")?

I've been contemplating the concept of tiny houses and, as a subset, boats. One major issue in both is interior condensation, but boats make it even harder since the exterior is zero-perms & about R1. Many folks avoid this issue by running for the Caribbean in the winter, but I'd like something more elegant. How can I insulate a curved zero-perm surface?

The most likely concept I've thought of so far is two (1/2"?) layers of flexible closed-cell foam continuously bonded to the surface beneath (yes, I realize this is incredibly time-intensive, but it is a small amt of surface).

In Energy efficiency and durability | Asked By Dustin Harris | Jun 24 13
4 Answers

Anyone use or explore precast concrete in residential construction?

Reaffirming that the "perfect wall" will have high thermal performance, not provide substrate for mold/decay organisms, provide exceptional strength (tornado/huricane/ falling trees and even ballistic resistant preferred) and be durable for a century or two, brings me to some form of insulated masonry (I am all ears if someone has another cost effective suggestion that fulfills said criteria). While comparing and contrasting ICF vs. some form of insulated CMU, I came across precast.

In Energy efficiency and durability | Asked By Sal Lombardo | Jul 3 13
3 Answers

Layering up siding on an old house

I have a house build in 1868, I have been doing an enormous amount of work on it since I bought it about 7 years ago. The house has the original clapboard siding covered over with asbestos siding which was done a long time ago and is looking very dated. I realize tearing off the asbestos, praying the wood underneath is in good shape and bring back the house to it’s original state would be great, but that would be very expensive and would insure a whole lot of work in the future to keep it painted if not work a lot of money.

In General questions | Asked By Dan Nardoza | Jul 6 13
3 Answers

Rigid foam for sound proofing interior walls/floors


In Energy efficiency and durability | Asked By Geoffrey Cook | Jul 10 13
4 Answers

"Protective covering" for exterior foam?

The attached detail suggests a protective covering that covers the exterior insulation at a basement foundation wall. What is a commonly used "protective covering" for this detail? Given the proximity to the ground and code requirements for clearance to exterior cladding, I'm stumped as to what to use here?


In Green building techniques | Asked By Stephen Brown | Jul 9 13
5 Answers

Solar Reflective Index

We are building a LEED for homes house and our client wants to use gravel for a driveway and some stained (grey) concrete for the sidewalks and patios. We need an SRI greater then 29. Have not found anyone that knows how to measure this - can anyone provide any help or suggestions?

In Green products and materials | Asked By Danny Kelly | Aug 27 09
4 Answers

Shades up or down for energy efficiency when working at home over the summer?

My husband and I work from home during the summer and are trying to figure out whether it is more energy efficient to have shades up for light or shades down to keep out heat and turn on the light during the hottest months.



In Energy efficiency and durability | Asked By Miriam Shakow | Jul 6 13
4 Answers

Are there any ductless GSHP systems?

It appears all of the mini-split systems available are air-source. Are there any mini-split systems designed for ground-source? All of the GSHP split systems I can find still require a large air handler and ducting -- is there a reason why small wall-mount or ceiling cassette units are not available as for ASHP mini-split systems?

In Green products and materials | Asked By Chris Schucker | Jul 6 13
1 Answer

Replacement of porch deck

We live in a 100+ year old home in Zone 4A. Porch is 12 x 38 and covered. It has been replaced many times but piecemeal by previous owners and now begs complete replacement of porch deck. We would like ti find composite matieral that would mimic the 21/2" tongue and groove boards used presently. We would need to either stain or paint in dark grey.


In Green products and materials | Asked By Daniel Roberts | Jul 8 13
13 Answers

First time General Contractor

First, let me begin by saying that I have never built a house. I have, however, lived in 2 homes that I had built. Also, I am a skilled in finished carpentry, tiling, plumbing, and can hold my own in general framing and electrical work. For over 35 years I worked in Information Systems (my day job) specializing in project management.

In Project management | Asked By Mike Turner | Dec 24 12
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