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9 Answers

Exterior walls to meet code without gypsum?

Hello,

Maybe this has been discussed here. Feel free to link me to other threads that I haven't seen if this is fully covered elsewhere.

I'm not a fan of drywall. A quick rundown with no real surprises: it used to be cheaper; now it's not. It also takes plenty of work and more money to make it look nice. It's heavy but also very breakable. Even when you don't break it, it's messy. Etc, etc. I *am* a fan of 3/4 plywood, which is less breakable, more durable, and looks nice.

In General questions | Asked By Minneapolis Disaster, 6B | Jul 22 16
0 Answers

polyurethane foam vs icynene foam best for subfloor insulation

I have a house that is brick veneer and the front section has the polished timber floors.
The sub floor area was not properly ventilated and we had some mould issues. Since then we have had vent’s installed and a sub floor fan under one of the rooms.
However it is a clay soil that the house is suspended on, there are still a some mould spurs on the soil. The air under one room is always quiet damp.

I was wondering if product is more suitable for this type of application ….does notabsorb the moisture in the air and will mould grow on it ??

In Energy efficiency and durability | Asked By rheems i | Jul 25 16
0 Answers

1903 home, first time with central air, lots of questions about insulating, ductwork, etc

Hello! Grab a cup of coffee and hopefully you will have a little insight on this! Thank you!!!!!!!!!!!!!!

I have an early 1900s 2 story victorian home 2200 sq ft, currently getting a new roof next month, and had to remove the old insulation on the attic floor that was outdated in roof preparation (in april). Blown in insulation was added to all exterior walls, as well as a thin sheet of foam fiberglass insulation, prior to installing vinyl siding over the wood siding about 25 years ago. Also storm windows to cover the old windows.

In Energy efficiency and durability | Asked By John Friend | Jul 25 16
9 Answers

Bowed gable-end truss

Today we got 18/19 trusses set and somewhat braced, more to go on bracing.

The problem we ran into is that the gable and would meet the wall in the middle, but both ends were off the walls. The walls are straight and flat.

I pulled the gable down and snapped a chalk line along the bottom of the bottom chord, and found that the center was lower than the ends by a good 3/4".

Having never set a pre-buiilt gable truss, I would think that it would be nearly impossible to load the top chord enough during installation to push the bow out.

In General questions | Asked By Mike M | Jul 24 16
70 Answers

Why haven't steel-framed homes become more popular?

I am in the planning phase of building a home in the NJ-NY area, Climate zone 5. As I investigate my options; SIPS, double wall stick 2x4 wood, 2x6 wood, ICFs, CMU, Larsen trusses, etc.. and the myriad of permutations to insulate each one (spray foam, cellulose, hybrid batt & flash, exterior rigid foam/iso panels, etc....) I came across STEEL. My goal is as high R-value as I can get within reason $$, with hope of upwards of R-30 final values. That said, I need some objective input.

In Green building techniques | Asked By Sal Lombardo | Dec 27 12
58 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

In Mechanicals | Asked By Dave De C | Jul 16 16
4 Answers

Blown-in insulation for existing walls

My circa 1900 house in West Virginia (Zone 5) has hardwood paneling throughout the interior and wood siding on the exterior with no insulation in-between the actual 2x4 walls. I'm pondering either blow-in cellulose or open cell spray polyurethane foam applied through holes in the siding. (Should I consider other options?) Both open-cell SPF and cellulose show an R-value of 3.2 to 3.8/inch. I understand the cellulose will settle over time leaving some gap at the top and foam will not. I like the idea of an air barrier provided by SPF between the leaky wood interior and exterior surfaces.

In Green products and materials | Asked By Andy Kerr | Jul 25 16
6 Answers

Air space required for GE Geospring hybrid electric heat-pump water heater?

I'm interested in going to a heat pump water heater and looking at the GEH50DFEJSR geospring model. I see in the manual it says it needs a 10×10x7 room or louvre door or duct kit. I'm curious if a vented pass thru to a larger room works the same? Kinda like a cold air return. The room is 8x5.5x8 and would rather not put a louvre door up. Any recommendations? Anything else I should know before purchase?

Thanks so much!

In General questions | Asked By Stephen Audretch | Jul 24 16
3 Answers

Open-cell foam and airtightness

I've seen reports from the foam manufacturers touting how much better the foam is than fiberglass of the same R value. They're essentially using the improved airtightness of the foam to show better performance compared to fiberglass with no air barrier. I can see it's mostly BS. I am wondering if you have a proper air barrier if open cell foam can measurably increase the air tightness of the structure?

In Green products and materials | Asked By Brad H | Jul 25 16
6 Answers

Preferred underlayment under metal on unvented roof?

Hi Everyone,
Need to make a final decision on which underlayment to use under a metal roof on an unvented roof system. The roof is currently built as follows: Beams on 5' centers; 1 1/2' T&G decking; 3/8" plywood diaphragm - seams taped; with TriBuilt granulated self adhering underlayment on top of the plywood.

Next I'll be screwing down 5 1/2"RayCore SIPS panels over heated space and framing boxes over the eaves covering everything with 5/8" CDX. Still looking at metal roof products but am zeroing in on a high seam (1 3/4") snap lock system. Roof pitch is 2/12.

In General questions | Asked By Robert McKee | Jul 23 16
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