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4 Answers

Cathedral ceiling ventilation baffle

I have a 12/12 roof over an attic that I am making into a storage room. I added 1/2" plywood onto the joists to make a rough floor. On one half of the roof a second roof was built over it at about 10/12 to extend the roof out over a porch. All three "roofs" meet at the ridge. I am building ventilation baffles between the rafters with 1x1's as the spacers and 5.5mm underlayment plywood as the baffle panels. The sheathing is old 1" boards on the rafters with 1/2" OSB over that on the single roof side. On the double roof side it is 1" boards throughout with OSB only along the upper 24" or so.

In General questions | Asked By Doug G | Jan 28 16
7 Answers

Cathedral ceiling venting?


Just looking for a little help with my Ceiling. I built a new log home this summer and made a mistake with my cathedral roof. I was told by a relative to use a new method of 1" of spray foam and roxul R30, the 1" of spray foam would be enough to not need to vent the roof.

In General questions | Asked By John Hunt | Jan 24 16
46 Answers

How to install bathroom exhausts in an airtight house?

I am in the planning stage of my new home build. I am planning on using advance framing techniques with 2x6 studs, 2" polyiso rigid foam on the exterior, open cell spray foam in the wall and unvented roof.

After all that effort and extra expense Im suppose to place 4, 6" holes in my wall for my bathroom exhaust fans with nothing more than a meta flap to keep air from coming back in? Same for my dryer's exhaust. Seems like a lot of air intrusion points.

In Green building techniques | Asked By Jeffrey Savage | Jan 7 16
8 Answers

How to properly insulate a vented crawl space?

From the articles I've read on this website I know most people prefer a basement, slab on grade, or a sealed crawl space to a vented crawl space. Unfortunately a basement isn't an option due to high ground water and apparently in Idaho (where the new build is taking place) the vented crawl spaces out perform the sealed crawl. There aren't any slab on grade homes in the area and our builder isn't familiar with them, so we are trying to avoid it if possible.

In Energy efficiency and durability | Asked By David Voros | Jan 28 16
6 Answers

Access to crawl space through masonry stem wall

My small, one-story, wood-framed house will be built on a masonry stem wall three courses (24") high that will support a raised wood floor. My locale requires continuous rebar along the top course, so the top course will be bond-beam blocks. I need to install an access opening through the stem wall (through the interior floor is not an option), and code requires at least a 16" x 24" opening.

In General questions | Asked By Jeff Cooper | Jan 28 16
2 Answers

Long electrical wiring home runs


In General questions | Asked By C. Maglio | Jan 28 16
6 Answers

Duct sizing for Fujitsu 9RLSFCD concealed duct unit

Hi All,

I am planning to install Fujitsu 9RLFCD concealed duct unit and can’t figure out way what size duct should I use and how to determine how many CFM does each room need. I have a heat loss done for each bedroom.

The plan is to put unit in the lower level aka basement (it’s split entry home) and run the duct work to the 3 bedrooms thru the floor. All three bedrooms are next to each other and would not require more than 4-6ft of ducts to each bedroom.

In Mechanicals | Asked By Alex Frost | Jan 28 16
4 Answers

Does OSB sheathing need to be installed horizontally over advanced framing studs 24"OC?

A client building in Zone 4 says their engineer told them, "in our wind speed and exposure (105mph - C) neither OSB nor 15/32” CDX can span between studs at 24”oc without being run horizontally". This is problematic because they are not planning on using rigid foam over the sheathing and are concerned about increased thermal bridging and air leakage resulting from expansion joints and additional blocking needed for horizontal installation. I have seen many houses with vertical OSB sheathing over 24" OC studs so this is new to me. Has anyone else heard of this?

In Building Code Questions | Asked By Elizabeth Coe | Jan 28 16
1 Answer

Cathedral ceiling with service cavity

I am building a vented cathedral ceiling, but am now looking at adding a service cavity to allow space for recessed lights without penetrating my air barrier.

I'm looking at some ultra-thin LED lights, which run about 1.5", so I was thinking I could simply use 2x2s or 2x4s laid flat against my existing rafters. The transformers are short as well and can fit into a shorter 1.5" junction box. They are designed to be placed directly against insulation, so they don't need any space behind them as well, though they'll still have 1" or so, and space all around.

In Energy efficiency and durability | Asked By Peter Hsu | Jan 28 16
9 Answers

Whirlpool HybridCare discontinued?

I was just looking on the Whirlpool website for some information on the HybridCare ventless heat pump dryer, and it is listed as discontinued!

I contacted them to confirm and find out if a new model will be coming out or if they are abandoning their heat pump technology, but have not heard back.

Anybody else hear anything on this?


In Green products and materials | Asked By Stephen Youngquist | Jan 27 16
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