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1 Answer

Retrofit insulation


I've got a 150yr old big house back house type farmhouse in Maine. Even though there was some blown in cellulous in the ballon frame construction, it's cold in the winter (exterior walls feel very cold to the touch).

I'm debating between the following for adding to the interior side of exterior walls right up against the lath and plaster:

1. Putting up sheets of foam with drywall backing (how many inches is the best efficiency/cost choice)? Any caveats?

2. Putting up a two by four frame then filling with roxul insulation http://www.roxul.com/products/residential/products

In GBA Pro help | Asked By DJ | Oct 5 15
6 Answers

R-values - are they different depending on direction of heat flow?

I have a contractor claiming that their reflective insulation (alarm bells, I know!) has a different R-value for downward heat flow than upward heat flow. Is that possible?

The material is intended to be installed under the roof shingles. I spoke to the manufacturer and he assured me that the reflective property doesn't work when in contact with asphalt shingles, but that the product has an acceptable R-value for "downward heat flow" to be eligible.


In General questions | Asked By Whitney Larsen | Oct 5 15
14 Answers

Ceiling insulation

Have several questions.

1. I found a lot of rigid foam (2.5 inch) in the ceiling which is laid over the cellulose insulation. I thought that the moisture will be kept under the foam. Do I need to take off all the rigid foam? or just leave it?

In GBA Pro help | Asked By Ben Yoon | Sep 28 15
7 Answers

Vapor barrier on DIY walk-in cooler?

Hello, I need someone to answer a simple question for. I have searched the web and gotten conflicting answers.

I'm building a 15X20 walk-cooler that will be kept between 35-40 degrees F. This is for storing poultry eggs on a egg production farm in Milton Freewater, Oregon. (NE Oregon)

Three walls will be inside the larger barn structure, which will be kept between 60-80 degrees F, the fourth cooler wall is formed by the exterior barn wall, facing west.

The design completed so far is as follows;

In GBA Pro help | Asked By Mahlon | Oct 4 15
3 Answers

Can I put Roxul over Sheetrock on the interior?

I was planning on creating a built in window seat/bed in a bonus room over the garage. We just purchased the house and I am guessing It's likely one of the coldest parts of the house in the winter. It's just above the garage doors. Likely has little insulation in the floor, vaulted ceiling so probably R13 at best. The house was built in 1991 +/-.

In Green building techniques | Asked By Andrew | Oct 3 15
2 Answers

Cor a vent rainscreen products

What's your thoughts on coravent SV3,Sturdy Strip,and Sturdy Starter?

In Energy efficiency and durability | Asked By Quinton Bryant | Oct 7 15
3 Answers

Wood burning stove below - what to do?

I live in an 1883 2-story farmhouse that was converted into 5 small condos in 1983 complete with wood burning stoves. Four of the units have had the stoves removed. The unit below me still has it and I swear smoke comes into my place when they use it. City allows except for occasional Action Days of no burning. I told the unit owner but she is out of town so I can't call her to come in and see for herself.
What would you do? Is there a way for me to test for smoke particulate? Picture attached -

In General questions | Asked By Mary Schwaba | Oct 6 15
4 Answers

Sidewall installation of dense-packed cellulose -- Many cavities are full of scrap drywall

Hi everyone,

I had posted this on the HomeImprovement subreddit, and was directed this way.

Anyone out there have any experience with retrofitting dense pack cellulose?

I've got a 66 brick ranch home with no insulation in the walls. I'm preparing to remedy that this week. I picked up my 1200 pounds of cellulose over the weekend and I've got a reservation for an Intec Force 2 blower.

In Energy efficiency and durability | Asked By Brandon McWilliams | Oct 5 15
8 Answers

Add rigid foam during re-roof

Our home on a barrier island 30 miles south of Wilmington, NC (close to NC/SC border) needs to have its shingle roof replaced. We’re planning on going to a standing seam metal roof.

If we know we want to eventually condition the attic, should we add rigid foam on top of our sheathing during the re-roof? Or spray foam the attic later?

If rigid foam makes sense now, what is the recommended type and thickness for this application?

Other house details
Climate zone: 3 Coastal
Built in 1947 (survived Hurricane Hazel!)

In Energy efficiency and durability | Asked By Robb Czyzewski | Sep 4 15
1 Answer

Insulating the exterior of a Rubberwall foundation -- hydrostatic pressure questions

(Zone 5A) 2 questions really

1st - have been using Rubberwall as my foundation sealer for years and been very satisfied with it. I usually will put a layer of some insulation on the rubberwall at the time of install to protect it but also when looking for a exterior insulation job. Lately I have been wondering if there are any redeeming qualities in the green colored rubberwall material. In other words is its manufacturing toxic or bad news in any way.

In General questions | Asked By Arthur | Oct 5 15
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