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9 Answers

Can interior basement insulation cause moisture damage to my sill plate or frost damage to my stone/concrete foundation wall?

Sources of technical information I have read on this are:
1. Retrofitting Basement Insulation, By Martin Holladay Issue 236 - June/July 2013
2. How to Insulate a Basement Wall, Posted on June 29 2012 by Martin Holladay, GBA Advisor
3. Hybrid Foundation Insulation Retrofits: Measure Guideline Building America Report – 1108, 13 January 2012 (Rev. 4/12), Joseph Lstiburek and Kohta Ueno

In Energy efficiency and durability | Asked By Charles Galgowski | Oct 10 16
14 Answers

Slab and foundation insulation for partially earth-bermed home

Hello GBA forum members! First post here.

We are building a slab-on-grade, two-story home that will have concrete walls on the north and west side of the 1st level. These sides will be earth-bermed and the south and east sides will be framed (sort of like a walkout basement). We will be putting PEX in the slab. We are in Wisconsin.

I am unsure of where to insulate the concrete. I want to try and keep all of it within the envelope.

Please see attached image.

In Green building techniques | Asked By Kevin Wright | Oct 11 16
8 Answers

SIP construction with Roxul on interior service cavity wall

I am new to the forum, but have been here a while reading allot of very informative posts. This seems like a great community to find like minded experts who are passionate about building environmentally friendly homes.

In Green building techniques | Asked By Rob Andrushko | Oct 11 16
15 Answers

Retrofit HVAC installation in Zone 6a

Our house is a bungalow (1200 sqft) with a 600 sq ft split addition near Toronto, Canada ~ 6A. It is reasonably tight (spray foam throughout).

Our HVAC Retrofit will include replacing an old oil boiler with a NG appliance and installing a ventilation and AC system. When making decisions about this retrofit, IAQ is our most important criteria, followed by operating cost. My wife has a few health issues that make IAQ very important to us.

The two systems I am considering are:

In Mechanicals | Asked By Joe McRae | Oct 7 16
7 Answers

Is our builder responsible for the wrong height of the ceiling?

We walked through a model home, liked the floor plan and choose to build that plan. Our home and one other home (with the same floor plan) were being built at the same time by same framers.

The ceiling in the hallway was a certain height to accommodate crown molding. The project manager came to us and said the crown molding couldn't go all the way around because of the height of the arches, so we could have it come around and stop on each side of the arch or lower the arches.

In GBA Pro help | Asked By Courtney Spitz | Oct 11 16
6 Answers

Interior foam, veneer stone, etc.

Wow, my second (plus) question! I have lurked for a long time, finding most of my questions answered by searching, but I have been having a hard time finding solid answers as my project plans get more specific.

In Green building techniques | Asked By Wayne Yamamoto | Oct 11 16
2 Answers

Use rigid foam as backing for 2x4 walls?

I have a 64x40x12.5 garage that has a 64x18x8 room above it that I will be using for a woodshop. I live in Vermont so it gets cold here in the winter. I want to insulate the garage and room above it in 2 different zones and put vents in the floor that I can just open up if I want to get heat up stairs. I wish I had the trusses designed so that I had a 2x6 wall upstairs. instead I have 2x4 walls. I wanted 6" of insulation. Would it be alright to use unfaced rigid foam (maybe 1" or 2") as a backing and then use 2x4 faced insulation inside?

In General questions | Asked By Charlie Doe | Oct 11 16
2 Answers

Brick house rainscreen space ventilation

1950s slab on-grade single story house in Southeast Pennsylvania

From outside in: brick, cinder block (I believe mortared to the brick totaling maybe 8 inches), black asphalt-type barrier paper, 2x2 studs, then drywall. There are weep holes on the outside of the brick.

My question is about the ¼ inch space between the cinderblock and the drywall that vents into the attic. Can that space be sealed at the top with foam without problems (mold, brick spalling, etc)?

In Green building techniques | Asked By Tim Buzz | Oct 11 16
5 Answers

Stove pipe through insulated panel

I'm in the process of building my roof and am running into an issue while trying to figure out the best method for proper air sealing a stove pipe installation. I have installed 3 inches of Polyiso on the roof and will be putting another layer of roof sheathing (OSB) on top and I have no idea what I should do about the stove pipe. I understand what to do with the stove pipe for running through the ceiling and protecting it from spray foam, but nothing about proper flashing.

In Green building techniques | Asked By Jacob Cox | Oct 10 16
5 Answers

Can't decide between two mini-split models!

Hi all -

The HVAC goes in this week, and I'm excited! This is a converted garage that will be used as a video studio, so it's not a living space but needs to be comfortable when needed. It would rarely be used in the middle of the night, but it could happen. The garage has been air sealed and insulated and I've had a manual J which said I need:

20,503 BtuH of heating
7756 BtuH of cooling

In Energy efficiency and durability | Asked By Dave H | Oct 9 16
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