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0 Answers

Rigid foam over existing drywall?

I'm planning on converting half my garage to living space, and I would like to add three inches of rigid foam insulation and another layer of drywall over the existing drywall.

The walls are 2x4 on 16" centers with fiberglass batt insulation, plywood sheathing (or possibly OSB), house wrap, and vinyl cladding. Can you think of any reason why this technique might pose a problem in my northeastern climate?

Asked By Ben C. | Jul 27 17
3 Answers

Humidifier and HRV in the high desert and other HVAC add-on items

We're building a 4200 ft home in the high desert (Bend, Oregon) and are debating several HVAC proposal add ons. The furnace plan is for a conventional ducted system with a Trane modulating furnace and variable speed AC. We unfortunately couldn't get over the split system interior look. The proposal had several add on items which seem controversial.

Asked By Ben H | Jul 26 17
2 Answers

Cellulose or BIBS fiberglass in 16" Ceiling Cavity ?

My house addition has an 800 sq ft ventilated attic. Ceiling joists are 16 inch I-Joists on 24" centers with 5/8 drywall underneath and 5/8 plywood attic floor on top.

The plywood attic floor is removable everywhere except the perimeter so that insulation can be blown from above into the 16" deep cavity. The current plan is to remove a row of plywood sheets on each side of the attic centerline. That will allow insulation to be blown from above and a maximum of 8 ft horizontally between the drywall and unremoved plywood.

Asked By Michael Tuso | Jul 24 17
0 Answers

Modified Edgewater Double Stud Wall

Marine Climate 4C

I have been working on a double stud wall design for a Pretty Good House. It is a variation the Edgewater design with inspiration from various other sources. I have redlined the air barrier.

It is close to complete, still working on some flashing details and material specifics. But perhaps good enough at this stage to share my progress.

Would appreciate any feedback or comment.


Asked By Tim L | Jul 27 17
0 Answers

Moisture control in unconditioned storage space under detached garage

Hello, we are building an unconditioned detached garage on a sloped lot in MD with a lower level that will be used as an additional garage space as well as storage for tools, power equipment, and even kids' toys and bikes. We would like to do our best to prevent rust and and mold in that space, but we have struggled with figuring out the best approach. This lower level space will be a 25'x35'x7' concrete cave with a slab on grade, a structural slab for a ceiling, and concrete walls that are on one end fully below grade, on the other fully above grade.

Asked By KarlaMD | Jul 27 17
1 Answer

Energy efficiency upgrades during residing.

Hello GBA community. Newer to the website and newer homeowner, but have been studying and reading about building science. I live in Zone 5, have a stick frame house built in 1995 (1300 sf single family, one level). It is nearing time to replace my siding (roofing too) and I want to have a plan for some needed efficiency upgrades. I am trying to keep it simple and cost effective. Want to make some improvements, but this is not my forever home. I'd like to hash out my plan and ask for some critiques. Really appreciate your feedback and insight.

Asked By Ryan Dutton | Jul 27 17
4 Answers

What is heating the floor in one room of my stilt home?

I live in the Florida Keys, in a frame home on concrete posts and beams. There is a carport with concrete pad on each side of a storage room at ground level, then two stories of living space. Double hip roofed. The house faces west. Every day in the summer, BEFORE THE SUN REACHES THE FRONT OF THE HOUSE, the floor in the room above the north-side carport heats up -- not the whole floor but eight feet or so nearest the front of the house. I measured the temperature rise and it is about 5 degrees - noticeable to a bare foot. The double window at the front is covered by a Bahama shutter.

Asked By hojgard | Jul 26 17
8 Answers

Curious on thoughts about insulation on a new house.

Will be building a house in southern ontario, cold in the winter hot in the summer. Been reading up on insulation techniques, as i like the idea of thermal bridging but hate the idea of trapping moisture in the walls as i have seen some ugly things over the years in renovations and what moisture can do. Im unwilling to put foam board on the outside and vapor barrier on the inside. Just seems wrong. So here is my thought. Build the walls, apply a one inch foam straight to the studs with a layer of plywood fastened overtop with tyvek.

Asked By user-6782048 | Jul 25 17
6 Answers

Install rigid foam while the wall is lying down

Has anyone tried installing the rigid foam EPS or XPS while the wall is on the floor deck and then installing the plywood over the foam overlapping foam seams before lifting the wall into place ?

Asked By susan cosentini | Jul 26 17
1 Answer

How to insulate the 'attic' of a 4' x 14' bump-out with hip roof.

This 100 year old house will be getting exterior insulation (3" SPF is current plan). The attic was insulated with SPF with venting for the underside of the roof deck. Intend to tie-in the attic SPF with the wall SPF therefore the soffits were removed.

There are 3 bump-outs that could compromise the continuous layer of of SPF that we plan to add. The largest is 4x14 (exterior wall size) and has a hip roof. It is currently insulated with pink fiberglass; seen from the eves. Likely done 20+ years ago when the last shingles were installed.

Asked By TIM LANGE | Jul 27 17
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