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4 Answers

Codes run afoul of advice when it comes to insulating my slab

A few months back, I asked about the best way to layer materials for my garage slab on grade with hydronic heating in MN (zone 6):


Consensus was to place 6 mil polyethylene vapor barrier ABOVE XPS insulation, directly beneath concrete slab. PEX tubing would then be stapled to XPS foam boards, and rebar on top of PEX.

In Building Code Questions | Asked By Kent Jeffery | Aug 29 12
3 Answers

Is it correct to use OSB material as a partial base under kitchen counters with granite countertop?

Is it correct to use OSB material as a partial base under kitchen counters with granite countertop even if all base seams sealed with a suitable calking material?
Contractor wants to use OSB board to help as alignment base for kitchen counter cabinets. OSB board to be layed over older,15 year old, maghoney underlayment which is in good condition.

In General questions | Asked By Gary Harris | Aug 30 12
5 Answers

Foam Insulation for a Post-and-Beam 1771 Saltbox

I'm restoring a saltbox built in CT in 1771. This house was built using traditional posts and beams, with 1 inch thick oak random width VERTICAL planks for the exterior sheathing. That was topped by clapboard siding. The plank sheathing was installed with no attention to air movement - there are vertical gaps between most planks, but in some areas there are gaps as wide as 6 inches! So I am looking for guidance on the best approach to insulating and siding this house.

In Energy efficiency and durability | Asked By Gary Everett | Aug 29 12
1 Answer

Mechanical sash operators for inside sash weight pocket


I'm trying to eliminate the iron sash weights and still get operable windows.

Somewhere in my travels I've seen ( at lest I think I have) springs or some sort of lifting mechanism mounted in a tube, that fits inside the sash weight pocket. I've been running into homes that have beautiful operable windows and trim that I don't want mess up with vinyl spring slides that are exposed. I'd like to put the "tubes" in the sash weight pockets and them foam them in to insulate and knock down the air leaks.

In Energy efficiency and durability | Asked By Steve Greenberg | Aug 30 12
3 Answers

Best wall system for my area and budget?

I will be building a 2,300 sf house in Nebraska, Zone 5A. It will be a two-story, 38' x 31' with four walls, an attached garage, and a 4:12 hip roof. Due to a small lot and houses next door, most windows face either the Northwest or Southeast.

I am on a pretty tight budget here, and was quoted the price for 2x4 walls. I can squeeze another $5-8k or so out of the budget to improve the wall system. What should I do? I was thinking 2x6 with foam board. Thoughts? Thanks!

(The floorplan is at the drafters right now, but I will post it later if anyone has any thoughts on it.)

In Energy efficiency and durability | Asked By Cameron Guenzel | Aug 29 12
2 Answers

Cost of air sealing and insulation

I just read the results of this research project by the EPA. In it they air seal a home built in the late 1970's and bring it from~ 0.93 ACHnat to 0.50 ACHnat. And they also add insulation to the attic (from R15 to R38), rim joists (from R0 to R11), and floors over the crawl space (from R0 to R11).

I'm wondering:

1) Is that type of air sealing accomplishment realistic in the real world without a deep energy retrofit?

In Energy efficiency and durability | Asked By Stephen Horvath | Aug 29 12
3 Answers

I want to place insulated glass units in a frame wall.

I want to place insulated glass units in a frame wall. At this point, the wall is studs with plywood sheathing. What is the best way to frame, secure and trim these IG units?

The middle window is 6' by 6'. Flanking units are smaller. Windows face south. The windows are fixed, glass only, no nailing fins. Exterior trim will likely be rough sawn walnut because it holds up to moisture. Located in SE Iowa

In GBA Pro help | Asked By Redstone Group LLC | Aug 28 12
3 Answers

How do we calculate skylight placement?

We are building a new house in DeRidder,Louisiana. Our walls are 8 inch cement block(featherlite rock face), 8 ft, 9 inch to top of block. Roof is 8 in 12. Kitchen faces directly south. Kitchen island runs from 6 feet inside block wall to 13 ft and is 4 ft wide. We want to install a velux skylight( GGL P10 3073 ) in the roof running long way with the kitchen island. We want the sun angles average north peremeter(probably noon, September 21) to stop at the north end of the 3 foot tall counter with perhaps soapstone on top of it.

In General questions | Asked By Catherine Tilton | Aug 29 12
2 Answers

Upgrading garage insulation

My bedroom is over an unheated 2 car garage. The ceiling has 2 heating vents running 20' which are not well sealed and show signs of moisture condensing. The 9.5" joist spaces have wedged in 6" fiberglass kraft faced insulation. The joist cavities are open to a ventilated soffit at the door end. I'm going to remove the insulation, seal the 2 heating/cooling ducts and use duct wrap their entire length. I'm going to spray 1" of isocyene foam on ceiling to seal the entire bedroom floor from the garage and then reinstall the fiberglass before reinstalling drywall. The house was built in 1992.

In Energy efficiency and durability | Asked By james savage | Aug 29 12
1 Answer

How do you detail a plenum space with ducts that is below an unvented/insulated flat roof ?

This is a multi-family project in zone 4b which will have a drywall ceiling. Above the ceiling is a 2' space where ducts will run. CCF will insulate the underside of the roof deck and the walls of this plenum space. So, ducts will be in conditioned space.

In Energy efficiency and durability | Asked By sue bryant | Aug 29 12
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