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1 Answer

Exterior rigid foam question

I live in the San Francisco Bay Area and am applying exterior rigid foam as follows:

plywood-2 layers of 3/4" foil faced polyiso - WRB -rainscreen - fiber cement lap siding

In many of the articles I have read on the subject, it recommends applying an adhesive on the foam on the panel edges were it meets the bottom of the wall and the perimeter wall edges.

In Green building techniques | Asked By Randy Mason | Feb 25 15
6 Answers

Air-source heat pump vs. AC/furnace

I am contemplating some different HVAC options in Connecticut (zone 5). I currently have an 80% efficiency Carrier Infinity NG furnace (8 years old) that can be paired with a Carrier Greenspeed heat pump. I can do that for $11,400 before incentives, or replace my existing and dying 10 SEER AC unit with a new 16 SEER for $8,000.

In Mechanicals | Asked By Anthony Kane | Feb 24 15
6 Answers

Insulating and air sealing kneewalls


I recently bought a house, and over the last few months have figured a number of issues with the insulation in the knee walls. A few notes about the house:
*In MN (Climate Zone 6, almost 7).
* ~20 years old
*Built with a poly vapor barrier on the inside behind the drywall
*2x6 framing, currently no sheathing on the attic side, R-19 fiberglass is currently in the kneewalls
*Only way into attic is through a 24x30 opening
*Due to the architecture of the house, I have many knee walls, ranging from 7.5', 4', and two that progressively get shorter as you go down a scissor truss.

In Energy efficiency and durability | Asked By Ross A | Feb 22 15
10 Answers

Questions on a "not-so-deep" retrofit...

1948 mid century/ranch, stucco exterior
Wood shaving insulation with paper face stapled to framing
2 layers of (I believe) "plasterboard" 3/8" over 5/8" = 1" total
Kitchen renovation found no evidence of moisture in the ceiling or walls, removed wood shaving insulation and replaced with R-19 batt (regrettably but can't undo now)
Polyethylene vapor barrier on interior side of renovated walls (insulation code official laughed when I said that I expected him to closely scrutinize the vapor barrier and he said, "There are so many holes in this old house [windows and doors], this r

In Energy efficiency and durability | Asked By Justin Merkovich | Feb 19 15
1 Answer

Insulating an old home

working on an old house, removed lathe down to the studs and the outside clapboard siding. There was no sheathing so what is exposed is the horizontal clap board siding. What is your recommendation for insulating the outside walls. Is it possible to use foam insulation (closed cell or open cell foam) directly against the siding or do I need some kind of air space between? If an air space, would15# black felt paper against siding be sufficient? the back side of the siding has never been painted. Siding is pine and 140 years old. Would appreciate any input.

In Energy efficiency and durability | Asked By John Conway | Feb 24 15
1 Answer

How to insulate a steel building?

As way of introduction I live in Fair hill MD on an acre lot.I consider myself to be a handyman and not afraid to do most of all the renovations to this gem in the rough!

In General questions | Asked By Vinny Rucinski, Jr. | Feb 24 15
2 Answers

Load rating for 2x4 by 2x6 post

We are adding a second floor over living area, the room size is 35' x 18.5'. We have divided the room into three sections with a two support beams in middle of the 18.5' section. What would the load rating be for the post if it is made of 2- 2x4 and 2- 2x6 hollow middle?

In Mechanicals | Asked By Tim Eicher | Feb 24 15
3 Answers

Liquid-applied WRB or Ice & Water Shield?

I'm in the process of trying to choose a WRB for a PERSIST home I'm doing. I've been planning for months to use Grace Ice & Water, but recently took a class taught by Peter Yost and started to rethink my choice. What spray-on/roll-on WRB can you recommend? Which ones have you used? Which ones self-heal/seal at penetrations?

In General questions | Asked By brad hardie | Feb 24 15
9 Answers

2/12 cathedral roof replacement


I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

In GBA Pro help | Asked By mark kessler | Feb 23 15
1 Answer

Flash and batt in northern Iowa

We have a new post-and-beam home. We've put in 3" of ccSPF in the walls and are thinking at adding R-13 kraft-faced batts over this in the loft. Because of the way the exterior walks are framed, there is 2" of spray foam between the interior studs and the exterior sheathing, except at the posts and beams. Is there going to be a potential moisture problem with using the faced batts?

In Energy efficiency and durability | Asked By New House | Feb 23 15
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