Community: Energy efficiency and durability

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4 Answers

Indoor Humidity Levels - Magnitude of Risk and Solutions

I have some questions about the risk posed by humidity levels in my house and how best to address that risk. I have read lots of stuff on GBA regarding the humidity issue. Mostly I am looking for confirmation that I am on the right track. Sorry for the length of the following in advance.

Asked By Patrick McCombe | Jul 25 17
18 Answers

Insulation question and new construction.... thoughts?

New construction, we are doing a non-vented attic to keep our HVAC ductwork in a conditioned space with foam on the roof deck. Come to find out, we can put foam in all the walls vs using bibs for the same price which surprised me. This will make for a tight house and this brings the question in my mind "what type of mechanical ventilation"? House needs to breath and have a good exchange of air.

House is a 2 story and about 2700 sq ft. 2 HVAC units will be installed. Biggest concern is a good ventilation system..

Asked By Thomas Roberts | Jul 20 17
27 Answers

Unvented cathedral ceiling interim remodel

I have a roof problem on a small section of 4/12 above the bathrooms. It is only about 15 feet by 10 feet of insulated ceiling. Background information.... We are in Enumclaw, WA, which is zone 4C, I believe.

My home was built in the early 80's as a Justus Homes kit. All of the ceilings are unvented cathedral construction as follows:
2x6 tongue and groove on the interiors
15 pound felt
2x6 on edge at 24 inch spacing

Asked By User-6883899 | Jul 11 17
1 Answer

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
3 Answers

What is the best way to reduce heat gain in South facing garages?

This forum has had a lot to say about how foil bubble radiant heat barriers are silly and a waste of money.

I'm interested in reducing the heat gain in my South facing garages from the intense high desert sun. My garage bakes, and my neighbors is quite cool and comfortable, for a garage. I know he has done attic ventilation above the garage, and installed a radiant heat barriers on the door.

Asked By pshyvers | Jul 22 17
3 Answers

Energy efficient dryer vent

I was looking for a suggestion on a through-wall dryer vent for 8" thick wall that's energy efficient?

Asked By Michael Brackett | Jul 22 17
7 Answers

1870s rowhouse rehab energy efficiency - radiators and radiant heat?

I'm looking for feedback on heating and cooling (and energy efficiency) for a large, three story brick, italianate 1870's row house (with low-sloping flat roof) - it's attached to the neighboring brick house on the south, with a few feet between houses with the neighbor to the north). This is a big (4000 sq. ft), brick, main street structure with massive walls and many average sized (15' x 15') rooms that can't be opened-up too much because of the existing structure.

Asked By humbleadobe | Jul 21 17
6 Answers

Insulating balloon walls

High I am renovating a 1927 Dutch colonial with balloon wall construction. Th attic is finished but will be taken down to exposed walls and rafters. The exterior will be resided on the second level with Hardy board fibercement clapboards. The ground level is one layer of brick over wood sheathing. The roof will be replaced with an imitation slate product (DaVinci roof scrapes). All the windows were already replaced (Trim line) Aluminum clad wood thermopane windows. My question is about insulation. I will be cutting a ridge vent.

Asked By eh413 | Jul 20 17
6 Answers

EPS under siding

Hi all, I have a weekend cottage on a lake here in middle GA that was built in the mid-80’s that is in need of some serious TLC. One of the projects I’m planning on doing is to re-side the house with Hardiplank lap siding. The current siding is cedar lap on top of 1” foil faced Expanded Polystyrene (EPS). The corners are set with ½” plywood and ½” GP particle board for shear strength. Currently, there is no felt or house wrap between the sheathing and cedar siding. Due to 10 years of lack of maintenance and woodpeckers; the current cedar siding is in really bad shape.

Asked By Rudi Schmoll | Jul 21 17
4 Answers

Cost-effective option for improving cathedral roof insulation?

Hello all, Hello Martin.

I've read a number of GBA articles and posts regarding how to insulate cathedral ceilings, but I'm hoping for suggestions on the best way to improve our specific existing condition.

I'm in coastal Maine, zone 6a. Windy spot near a coastal river, not much shelter.

The 25 x 25 main wing of my 14 year-old house has a scissor-truss roof, with basic asphalt shingles in relatively good repair.

Asked By User-6889078 | Jul 21 17
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