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1 Answer

Insulating half a roof, from the top. What to use?

Location is climate zone 6.

Have a home with straight gable. The client wants to replace just one side of his roof/ceiling with new insulation. Attached is a photo of what the previous contractor did on the other half of the roof. Roof/ceiling is cathedral and thus the only space available is rafter bays/ possibly adding insulation on top of rafters. The roof must be accessed from the top after removing the sheet metal. With such limited options (and only being able to improve half the roof) what would be my best option for insulation/improving this bad situation?

Asked By Brad Allen | Aug 5 17
4 Answers

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
2 Answers

Pipe sleeve and under ground conduits through foundation : how big is too big?

I am building a slab foundation, with 4'6" frost walls and 24"X8" footings. The front corners of the house and garage are about 20 feet apart. I would like to sleeve the foundation walls so I can run conduits between the buildings, for future services. The questions:

(1) Ideally I want to run 3 separate 2.5" conduits between the building. As such, a 6" PVC sleeve through the 8" wall will not do. I will need an 8" sleeve. Is that too big for an 8" poured concrete wall with no rebar? Are there rules that determine how far up it has to be from the footing?

Asked By Mai Tai | Jul 26 17
6 Answers

Will R-70 cellulose sag ceiling drywall 24" o.c.?

My plans call for an R-70 ceiling of loose-pack cellulose in double-netted bays between trusses 24" o.c., with 5/8" Type X drywall holding it up as my air barrier. My installer says this will weigh about 2.55 lbs/sq/ft. Is this too much? Will it sag over time or pop screws? Do I need to use some special (expensive) low-sag drywall? I don't want to go to the expense and lost clearance of, e.g., an OSB layer above the drywall.

Anyone have experience with this?



Asked By Randy Jorgen | Jul 16 17
32 Answers

Minisplit sizing and number of minisplit heads for this apartment?

Hello Martin and Dana,

We continue to progress on our project and are about to have the rough electrical started. As a refresher, this is the 700 sq. ft. apartment inside a post-frame construction shop building in climate zone 3.( My last dilemma I needed help with was a question about insulation between studs along with exterior insulation)

I am talking with an HVAC contractor who specializes in Mitsubishi products. I realize you get 20 questions per week exactly like what I am about to ask, and I appreciate the patient help.

Asked By John Peeper | Jul 13 17
6 Answers

Best insulation and sealing for a tucked-under-garage ceiling?

We are purchasing a circa 1966 Cape in the Philadelphia are with the garage tucked under the master and guest bedrooms and two baths. The garage ceiling is currently covered with Homasote, but there are small areas where we can see an underlying plaster ceiling with missing chunks. The joists are 2x10s and there appears to be some fiberglass insulation batts in place.The HVAC ducts run below the joists and are mostly covered in Homasote, but several feet of ducts near the overhead door opening are exposed and uninsulated, but with remnants of asbestos.

Asked By Geoffrey Simon | Jul 17 17
2 Answers

We are purchasing a circa 1966 Cape in the Philadelphia area with the garage under two bedrooms and two baths

The garage ceiling is covered with Homasote but there are small areas that you can see an underlying plaster ceiling with missing chunks.

We are homeowners with an enduring passion for houses. We previously designed our own home in 1995, then enjoyed 20 years there. I am a retired Doc who reads FHB for fun!

Asked By Geoffrey Simon | Jul 14 17
10 Answers

Confused and worried about minisplit sizing

We’re building a house in Toronto, two stories (both about 1500 sqft each), first floor R26, second floor R32, second floor ceiling R70, with HRV, de-humidifying system, window-to-wall ratio 12%, windows mostly face east and west, windows are Fibertec high-efficiency, fiberglass frame, low e-coating. Whole house will have hydronic floors for heating. We’re planning Mitsubishi mini-splits for A/C, but we’re very confused about sizing and placing of heads (and outdoor units).

Asked By Thomas Kaempfen | Jul 9 17
3 Answers

Hardie lap siding vs. Boral siding

We are building a house in NH. Hardie is less expensive material, but more expensive labor. What about durability? Hardie has had a bad reputation. Have they improved their product? We can't find how long Boral has been available. Any word on problems with Boral?

Asked By Frank Torti | Jul 10 17
2 Answers

Accessing isolated part of attic

In all areas of my attic where the main attic/roof intersects a section of the roof with a perpendicular gable (e.g. at a dormer), there is an access opening for that sub-section of the attic. There is one exception, and I want to safely access the isolated section.

I can tell by both measurements from the center of the main roof, as well as confirmation by the absence of roofing nails, the section I need to cut, but I was wondering if anyone had any other tips on what I need to be careful of before cutting.

Asked By David Johnson | Jul 3 17
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