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10 Answers

Humidifier with a flash-and-batt house?

Hello. We are building a house in Virginia and the construction of the exterior wall is: Hardiplank, Tyvek, OSB, 1 inch closed cell spray foam, kraft faced R19 batt, and Drywall.

Our HVAC contractor is not installing the humidifier as he says tight homes don't need them. His comment was we might be calling him to install a Dehumidifier in all probability.

Is that true?

In Energy efficiency and durability | Asked By Susan Larkins | Dec 14 14
2 Answers

Sprayfoam house and real stone cladding. Wall sheathing?

Good day,

This is my first post, but I want to comment how much I've enjoyed reading topics on this q&a forum.

My question is regarding a new house I'm building. Zone 8 climate (cold!) similar to Alaska, 2x6 framing 16" OC walls, 1/2" OSB sheathing, no basement. Right now I'm just finishing up framing.

I've been dead set on using closed cell spray foam all around...on the interior wall cavity at 3" thick, 4" on the roof deck and 1.5" on the floor.

In General questions | Asked By Mark Helmrich | Dec 15 14
17 Answers

Sealing bottom plate to slab

My framer says that Sill Seal does not do a good job. I am inclined to agree with him. He is recommending a bead of liquid nails. I have been looking for real information. Certainly by now there have been some test run to measure the efficacy of various products and methods. And a new home slab is not a laboratory. How well does this or another product stick to a slab that has been wet and muddy?

In Green building techniques | Asked By Hugh Stearns | Aug 28 13
9 Answers

What about installing a cooktop downdraft vent/ducting in a slab?

I have installed two cook top downdraft vent/ducting systems with great success but never in a slab. In this case the duct would be embedded in the concrete slab with exterior grill through the perimeter foundation and still above grade. What should I look out for, take into consideration?

There will also be a return from an HVR system in the Kitchen area. (Thanks to the excellent article by Martin I am in dialog with Zehnder)

In Mechanicals | Asked By Caroline Di Diego | Dec 14 14
3 Answers

Attic ventilation

The information available on your site is awesome, so thank you for making it available to others.

I'm located in 2A region, a coastal county in Texas. I recently purchased an approximately 1120 sq ft farmhouse built in the 1940's. The home currently has three turbines in peak areas, each within about 10 feet or less from a gable vent. There are no soffits; the roof hangs over about 8 inches (in most areas) and has about 2 -4 inches, ( most areas) above the top plate under the roof interior. The HVAC is in the attic space.

The house is basically a "T":

In General questions | Asked By N Madrid | Dec 15 14
84 Answers

Modern (hydronic) heating and what all should start to know as of 2014

I stumbled upon this site to do with researching an update to a (hydronic) heating system I installed two decades ago.

So much has changed mainly the best change is the access we all have now to information.

This is the best read I have had off the internet to do with modern current (hydronic) heating.

Dana, besides your wealth of help here, this pictorial is great for the visual types like me.

http://www.duluthenergydesign.com/Content/Documents/GeneralInfo/Presenta...

In Mechanicals | Asked By aj builder, Upstate NY Zone 6a | Dec 4 14
8 Answers

To install engineered hardwood flooring over a basement slab, can I use (2) 3/8" CDX plywood over 1/2" XPS?

QUESTIONS: Can I use 2 layers 3/8” CDX Southern Pine plywood (joints staggered, glued & screwed together, but NOT mechanically attached to the slab) over 1/2" XPS? Whether I install the plywood sheathing over a vapor-retarder or rigid foam insulation, is CCA treated plywood necessary in either case? Which installation method (e.g. rigid foam or vapor-retarder) do you recommend in view of my concerns below?

In Energy efficiency and durability | Asked By Kevin Peters | Dec 11 14
8 Answers

To install engineered hardwood flooring over a basement slab, can I use (2) 3/8" CDX plywood over 1/2" XPS?

QUESTIONS: Can I use 2 layers 3/8” CDX Southern Pine plywood (joints staggered, glued & screwed together, but NOT mechanically attached to the slab) over 1/2" XPS? Whether I install the plywood sheathing over a vapor-retarder or rigid foam insulation, is CCA treated plywood necessary in either case? Which installation method (e.g. rigid foam or vapor-retarder) do you recommend in view of my concerns below?

In GBA Pro help | Asked By Kevin Peters | Dec 11 14
14 Answers

PV, electric autos, and the saving grace for utilities

Dana, this sounds like you... interesting how the future has changes the save us from... changes...

In Energy efficiency and durability | Asked By aj builder, Upstate NY Zone 6a | Dec 9 14
1 Answer

Preferred home characteristics for auditors/retrofitters?

Hello everyone,

This is my first post here at greenbuildingadvisor. I know that auditing companies/retrofitters will often screen homes with surveys, or by collecting publicly available information to determine whether or not a home has potential for energy savings.

In General questions | Asked By Henry Sims | Dec 14 14
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