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1 Answer

Can I install mini split units on the same wall?

I'm looking to install a 19 SEER Mitsubishi 24000 BTU mini split system on my garage. I'm limited in where I can put the outdoor unit, so my desired location happens to be directly behind where I want to put the indoor unit. The wall that will separate the units is 2-layer brick, so I expect that the lineset length will only be a max of 3-4 feet

In Plans Review | Asked By Elliot Boyce | Jan 11 15
1 Answer

Air-sealing in frigid weather. Can foam or caulk?

My house is bone dry (humidity in the teens). I know most of my walls are empty and likely I will not be blowing in dense pack cellulose until spring. So I have a house with air coming in at baseboards on the 1st floor. See IR camera picture attached.

I also have could areas around doors where I removed the trim and I can see outside trim through the gaps.

In Energy efficiency and durability | Asked By Apollo S | Jan 11 15
11 Answers

XPS vs. polyisocyanurate

I am currently redoing the exterior of my house with a new vinyl siding and changing all windows. My house was built in the mid 80's and have 2x6 studs with Batt Insulation and mostly without a vapor barrier... but the insulation is not great, especially the air goes through the house.
My question is what is the best insulation for me to put outside the house underneath the vinyl siding. My windows will allow me to go up to 1 inches of exterior insulation.
So XPS with Typar? Polyisocyanurate (IKO Ener Air )? Others?

In Energy efficiency and durability | Asked By Jason Haché | Aug 29 14
5 Answers

Infloor heat in basement and/or HVAC plus wood heat

I am building new in NW Wisconsin. Tight , well insulated, SIP walls and insulated basement but not passive house. My architect wants hot water heat in the basement slab and 1st floor bathroom floor.He also would like an HVAC system for supplemental heat and AC. I want a centrally located Tulikivi masonry wood heater on 1st level. House will be 2000 sq. ft. basement and one level above basement. No solar. My question is: How much heat is passively carried from the basement to the 1st level. There will be an open stairway to basement. Does radiant heat travel through the wood floors?

In General questions | Asked By terrance kaase | Jan 5 15
2 Answers

Firestone ISO-R foam. 1" R value? Worth keeping?

The previous owners had our house (1957 bungalow in Zone 7) wrapped with 1" Firestone ISO-R foam and then vinyl siding nailed onto the foam.

Not only is 1" not enough for zone 7, the contractor just laid the foam directly over the old cedar siding, as far as I can tell this is useless because of the giant air space behind the foam.

I'm in the process of stripping the exterior to the wood plank sheathing and planning to add 2" of foam to achieve the R-10 required.

In Green products and materials | Asked By Dan FromRegina | Jan 9 15
6 Answers

External foam board when using siding and stone / brick


I am embarking on having a home built in lucky zone 5. I was hoping to use some green building techniques where possible and not cost prohibitive. The current exterior is planned to be stone base and LP smart siding.

In Green building techniques | Asked By Michael Donahue | Jan 7 15
7 Answers

I am building a new home in nw Indiana that will be spray foamed through out.

1800sq ft ranch-2 inches eps under slab in basement. 2 inches closed cell on basement walls 3 inches in rim joists 2 by 6 walls filled with open cell on above grade. 3 inches of open cell covered with 10 inches of cellulouse in attic. We have a catheidral ceiling in the great room that will be 2 by 8 filled with open cell. Vinyl siding on the whole house with anderson 400 windowes. This is our proposed home Wonderihg about moisture and heating system.

In Energy efficiency and durability | Asked By tom thiesen | Jan 10 15
6 Answers

How should I air-seal and insulate a tongue-and-groove cathedral ceiling?

Six months ago, I bought a 1964 ranch house in Northeast Ohio (climate zone 5). The house has a cathedral ceiling throughout, with tongue-and-groove boards attached directly to the roof joists. There are currently old fiberglass batts up there for insulation, right on the tongue-and-groove boards, with some space above the fiberglass for air to pass through (we have large continuous soffit vents on the front and back eaves, and a continuous ridge vent).

In Energy efficiency and durability | Asked By Albert Orchard | Jan 9 15
12 Answers

Placement of two minisplits


I'm building a 1789 sq. ft. home in zone 5 near Hannibal, MO. I've attached our plans. The front door faces due south. My two questions we have are
1) What would this group recommend as the best location for the two mini-splits we hope to use in our home? The current locations are marked with red arrows on the plans.
2) With the cathedral ceiling on both floors, how far up on the wall should we place each unit?

Here's the details:

In Mechanicals | Asked By Jeff Carroll | Jan 6 15
3 Answers

Best way to improve 2x4 stud wall air sealing in 1960's house ?

A friend is renovating the living room in a recently purchased house that was built in the late 1960s. Location is in the mountains of Virginia, climate zone 4. The exterior wall construction (outside to inside) is: Horizontal lap siding, diagonal board sheathing, asphalt felt paper, 2x4 studs with kraft faced fiberglass batts, interior plywood paneling.

My friend is removing the interior paneling, partly because there are no protective metal plates over the wiring routed through studs. He plans to add protective plates then cover the walls with drywall.

In Energy efficiency and durability | Asked By Michael Tuso | Jan 9 15
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