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3 Answers

Dense-packed cellulose in exterior walls

I have a 100+ year old home and there is currently no insulation in the walls. There is vinyl siding on the exterior and I think it was installed over the old wood siding. I am considering having dense-packed cellulose blown into my 2x4 exterior walls. Am I going to have a moisture problem if I do so? I've read conflicting opinions. I would appreciate any advice you can offer.

Asked By T S | Jul 2 15
7 Answers

Relative value of air sealing at exterior sheathing

I am trying to understand the relative value of air sealing at the sheathing. To do this lets consider cost as the benchmark. I realize that there is value beyond cost but this is an easily quantifiable benchmark and the one that seems most resonate with my clients.

Asked By Hugh Stearns | Jul 1 15
3 Answers

Do sumps pumps and drain tiles create a self fulfilling prophecy?

This may seem like an odd question so let me explain myself, and to be clear it is mostly philosophical and out of curiosity.

I own/have owned/lived in many different buildings in the Chicago area. My parents house is also nearby.

Asked By Michael D | Jul 6 15
4 Answers

Solar orientation design trade-offs — tough decisions

I have the unique opportunity to build an net-zero spec house for an investor in my local area. It's a 1450 sq ft. ranch with a garage on a slab. Building to "pretty awesome" house principles. Air-tight, High R, Triple glazed euro windows, etc etc.

My dilemma is the trade-offs between curb appeal, design functionality and optimum solar orientation for solar PV and glazing.

Asked By Ben Freed | Jul 6 15
1 Answer

Recap: Insulate shop with polyiso between rafters

(Removed from an old thread with a similar title -- I decided to repost this as a separate question)

I am back working on my shop. To recap, it's a small 12' x 20' detached shop, in Mass., vaulted ceiling, well-vented at ridge and soffit, using 2" cut-and-cobble polyiso installed below plastic vent channels in each rafter bay, it's a low ceiling with no room to put the polyiso below the rafters.

Asked By Tom R | Jul 7 15
7 Answers

Insulate shop with polyiso between rafters?

Hi Folks ...

[I am new here, but have read through enough posts to see that what I'm asking about seems to be within the normal range of discussion, but not answered directly by anything I could find.]

I am in MA (zone 5). I have a 12' x 20' prefab shed that is used as a workshop. It was insulated with fiberglass batts between the 2x4 (yes, 2x4) rafters. There was 3/8" plywood below these covering the rafters, but not all the way up to the peak -- top foot or so on each side was just the open insulation face.

Asked By Tom Rawson | Dec 29 14
6 Answers

Window replacement

Hi.... I am helping a friend reconstruct an exterior wall, and will be replacing a window. The window purchased (and non-returnable) is a replacement window type.

Since we will be removing all the siding for the reconstruction, I assumed that a regular flanged was purchased.

Asked By Rob Henderson | Jul 6 15
6 Answers

Are there any builders, architects, engineers, or homeowners interested in industrial hemp building?

Energy and bio-friendly materials significantly solve many issues I see here, and despite code/cost and other issues, it is a solution many are embracing...

Hempcrete, hemp fiber insulation, hemp particle board, carpets, furniture are all available and becoming more mainstream alternatives with immense positive experiences. Anybody have experiences or interest in this?

Asked By Kristin Steen | Jun 16 15
6 Answers

Best practices for cutting foam?

What are people doing to cut EPS foam and control the dust and debris generated, considering the toxicity of the fire retardant chemicals in it?

Some argue the fire retardants are OK, because they don't leach out of the foam much. But it seems to me that the environmental release is probably dominated by the dust and debris generated.

Asked By Charlie Sullivan | Jul 6 15
16 Answers

Boiler upgrade recommendation?

I’m currently looking to upgrade my old boiler as it developed a small crack and is leaking. My current boiler is a P-468U-wt (151,000 btu/hr) Weil-McClain oil-fired boiler with a 40-gallon hot water holding tank.

I’m getting two different suggestions from two of my plumbers and would love some input on their recommendations. One recommends replacing it with an Energy Kinetics System 2000 and the other one is suggesting a Navien Combi-boiler.

Asked By Joe Pavia | Jul 1 15
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