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4 Answers


I know this has been debated, but I am just curious as to some more outlook on the best option here. I just ripped out a bathroom with one exterior wall. The wall was insulated with foil-faced fiberglass batts --- after ripping them out I saw they had mold on the side contacting the house sheathing. The home is 100 years old --- wood sheathing with stucco outside.

In General questions | Asked By Jason Schatz | Dec 30 11
6 Answers

My 50+ year old house has a walk-in attic that we use for storage. There is moisture on the roof decking and some mold in the winter. The soffits are vented, there are 2 gable vents and a roof fan. The mold is mostly on the side that faces north and is more toward the roof line than the peak. I have weather stripping on the door and have glued 1" insulating foam board to the door in hopes of reducing heat entering the attic via the door. I have tried to seal off as many source of heat entering the attic that I can find. There is about 6 inches of insulation, not sure of the R value.

In General questions | Asked By Morris Goldstein | Dec 29 11
10 Answers

It seems to me that cisterns are most valuable in the summer for irrigation purposes and in the winter are not used. thermal storage can be used more in winter for space heating as well as domestic water, especially with radiant floors. Insulating the cistern and having a heat exchanger that could be disconnected in the summer and the solar go directly to a Solar water heater for domestic use would make the tank twice as useful.

In Mechanicals | Asked By boone guyton | Sep 26 09
1 Answer

The gas line into the fireplace surround has a perforation to insert the line. Does the opening need fireproof foam added, since it is an interior wall?

In Energy efficiency and durability | Asked By steven churney | Dec 29 11
1 Answer

I've been reading a bit of information about the best places to put windows for energy efficiency. I know in Passive Solar buildings you want to minimize or eliminate north-facing windows. But does this rule still apply when doing a solar tube skylight?

In Green building techniques | Asked By Jason Schaffer | Dec 28 11
11 Answers

I have an 1,100-sq.-ft. 2-story Cape with two 14 ft. dormers for bedrooms on the 2nd floor. It is 90 years old, currently gutted. I want to insulate it well, but within some equitable reason.

Currently, the house has 1/2-inch rigid foam, R-3.6, on the exterior walls. I want to spray the roof line and enclose the whole envelope.

In Energy efficiency and durability | Asked By Scott Jacobs | Dec 21 11
6 Answers

First question ever asked here. We're building a shop in Upstate SC, mixed humid climate. We are insulating it for comfort so it can easily be used year round. We chose mineral wool insulation for its fireproof properties. The studs are 2 x 6 so they are using 3" mineral wool and 2" mineral batts. They have used a minimally expanding foam around all the studs, electrical outlets, any penetrations. That looks good. I am concerned about the compression as they stuff the mineral wood in. I've got a few pictures I will try to attach.

In Energy efficiency and durability | Asked By Lucy Foxworth | Dec 25 11
10 Answers

I own a log home in Southern Ohio with the primary section having a cathedral ceiling and smaller part conventional truss built roof.

In Energy efficiency and durability | Asked By Chip Young | Dec 20 11
19 Answers

Hi GBAers! Just joined and this is my first post, and it's a noob question from someone who's never built a home before: how "real" are heat studies, really?

To help me understand how to build my net-zero home, I've created some spreadsheet-based heat studies. From my simplistic and idealistic studies, I've learned that with little infiltration, good ventilation with recovery, and great insulation, it appears possible to build a net-zero home here in at 4200 feet in Salt Lake City proper. [1]

In PassivHaus | Asked By Jan Nielsen | Dec 21 11
3 Answers

(Zone 5, Des Moines, Iowa 1,100 sq ft, 1 story with dormer upstairs 1920's built)

After deciding to finish our basement, I had a radon guy out to look at the house for mitigation since our 2 home tests were a little above the '4' actionable level.

The guy was knowledgeable and looked around and pointed out that we have asbestos 'paper' wrapping the old part of our forced air ducts that we should paint over with an oil based paint to 'contain' it.

In General questions | Asked By John Rousseau | Oct 19 11
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