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4 Answers

Vapor barrier in attic?


Asked By Lucy | Oct 4 15
8 Answers

What are your thoughts about studs left un-drywalled?

I saw photos on Houzz of exposed interior wall studs - Prentice Architects and HS2 Architecture.
What are your thoughts? The light is attractive. What are your thoughts?

Asked By Mary Schwaba | Sep 29 15
5 Answers

Limited soffit venting clearance for baffles + insulation

Just installed a new roof with Maximum Ventilation exhausts and removed old fiberglass batts. I was originally planning to do the standard R50 fiberglass blow-in and soffit baffles. However, I discovered that in this 1960's back-split, the roof is quite shallow and rests directly on the double brick wall so there is only 3-4" clearance for soffit venting, leaving only 1-2" left for insulation under the baffles around the perimeter. This seems like a recipe for cold spots.

Some options:
1. Just proceed as planned; hopefully cold spots won't cause condensation on the ceiling.

Asked By Deb N | Oct 8 15
13 Answers

HVAC selection help

My new house is under construction and I need to finalize my HVAC system soon. Some details:

Zone 4, 3800 sq feet (About 1900 first floor, 1550 second floor, 350 room over the garage), crawl space (conditioned), open web floor trusses for second floor.

I had the manual J load calc reviewed by an engineer and have sent it back for some corrections (there is better insulation than is shown and better air sealing, and a couple other things which will lower the load. He didn't add the ventilation load though, which will raise it), but as it stands right now:

Asked By Michael Geoghegan | Oct 7 15
2 Answers

Attic insulation

We are in NE Oklahoma (Zone 3). Looking for advice on insulation for the roof.

Planing on batts in the walls, with 3/4" -1 inch foam on top of sheathing and Hardie siding.

The builder thinks we should foam the roof line.

The house is 24x42 rectangle with a 12/12 pitch roof, 9 ft ceiling both lower floors, with an option of a bonus room in the 3rd floor. Maybe put some mechanicals up there as well.

We will have a total electric central heat and air.

Asked By Quinton Bryant | Sep 28 15
2 Answers

Insulation type, etc.

hi all,

i have a semi-detached brick 2-family home in brooklyn. 20' x 65'. tenants are on the top floor and we occupy the first 2 floors. our ground floor is about 3 feet in ground on 3 sides and at grade in the rear. we are renovating and intend to put 2 full bathrooms and 3 bedrooms there, in addition to the laundry and utility room. we recently install a navian ncb240 which currently serves our dhw and baseboard radiators for both floors (tenants have separate boiler).

Asked By Josh Millis | Oct 1 15
1 Answer

Venting an existing flat roof

We have a row house in Chicago. The drawing indicate (it seems it was built as drawn) that we have a 1/4" per foot modified bitumen roof. We don't have soffits or ridges (just parapets on three sides and a gutter along the back). The roof structure is min 16" wood roof trusses at the low gutter end and they get bigger at the front. We have R49 Green Fiber blown in cellulose insulation in the trusses. There is no vapor barrier (as the insulation suggested) and there is two layers of 5/8" drywall at the ceiling. We have mushroom vents at 1 sq. ft. of net free area for every 300 sq. ft.

Asked By Trisha Megan | Oct 8 15
1 Answer

What is best insulation process for an addition?

We have a mobile home built 2007. We are adding an addition on the north side, 14 feet out, 70 feet long. Do we use 6 inch walls or regular 3 inch walls? With what type of insulation? We live in southern Illinois where it can get below zero. Also, will we need another heating source? Furnace is all electric, Vexar by York. We are trying to keep this affordable to heat and cool efficiently.

Asked By Victoria Harmon | Sep 30 15
9 Answers

Antique house #1: Cedar Roof

I will likely be taking on a crazy project in the next few months - buying an old house in Rhode Island, and improving it, on speculation.

The general scheme is to
--Do minimal work on the older (about 325 years) portion of the house,
--Expand/rebuild the newer (about 115 years) section with modern kitchen, baths, windows, etc.
-- Remove ugly garage, breezeway, and dormer.

Asked By curtis betts | Sep 30 15
1 Answer

Is R-13 x 2 greater than R-21 (for a 2x6 wall)?

Two layers of R13 batt insulation is cheaper than one layer of R21 batt (for a 2x6 wall). Can I place 2 layers of R13 in the wall and achieve a greater R value than one layer of R21?

One other note: Unfortunately the R13 is faced. Would two faced layers cause a problem?

Location-Southern California-92705

Asked By Keith Messick | Oct 8 15
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