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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
14 Answers

How do we address thermal bridging and insulation in Alexander, NC, zone 4, about 2800' elevation?

Wow, I have spent countless hours reading your articles and blogs. Much to my husbands chagrin! We have already built a garage with an apartment above it in WNC, zone 4. We used certainteed cement board siding, tyvek, OSB, 2x6's, 5.5" open cell in walls. The roof deck was sprayed with 8" of open cell and is unvented. (The Hvac is up there and from what I have read we should probably have supply and return ducts up there to keep moisture from becoming an issue... We are considering adding more insulation on the attic floor. But that will be another post .)

In Green building techniques | Asked By Kristin Taulbee | Jan 8 15
4 Answers

Roof trusses — Why not whole-house trusses?

I saw the picture of the attic room roof truss in this recent discussion http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an... and was also recently looking at double stud and Larsen truss building methods and it struck me, why not incorporate the roof truss into the double stud wall so that the house is assembled just like a roof is?


Fast, Structurally superior to "stick" built house with proper racking considerations, Integral energy heel and structural thick walls with minimal material and fuss.

In Green building techniques | Asked By Joseph Malovich | Jan 9 15
5 Answers

Basic beginner air sealing questions...

I'm in the learning process and I would like some advice on air sealing. I live in southeastern NC, near the coast. I have a fairly new 1900 sq ft home, built in 2010. The house has a slab foundation with an attached 2-car garage. No cars are kept in the garage. It is mainly just storage for mowers, tools, etc. The house is a single story except for a finished room over the garage. The attic is unfinished and vented. I have a heat pump. All the duct work is in the attic, which I know is a problem, but not something I'm currently up to tackling.

In Energy efficiency and durability | Asked By Jason Dennis | Jan 8 15
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