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17 Answers


Hey everyone, I'm new here, so please bare with me if I missed something.

After reading this forum for a little while, I'm convinced that doing things right (particularly insulating) is not a question anymore. Me and my fiance just bought our first house (Northern NJ) and need to replace the roof. We got a couple of quotes from the local guys, but most did not react too well when I asked about insulating the roof. GAF does not recommend it, or it is not necessary (one guy said R25 value in the attic is plenty for our area).

In General questions | Asked By Eldarchik | Jun 14 17
4 Answers

Add on demand to boiler system

We have a baseboard hot water boiler that is also used to heat our DHW(built in 1988). Seems we have larger than average gas bills even in summer. I have noticed that the boiler comes on even after 1 shower.
I am not sure if the temp set points are too low, boiler needs inspection, or to eliminate the side arm from boiler to DHW( Then add an on demand water heater). Bill over $100 mth seem very high for 2 people.

In Mechanicals | Asked By Bill Skaff | Jun 15 17
16 Answers

Blending energy efficiency with attractive design: “Boxy But Beautiful”

Is there a good source of images or ideas for Passive, Net-Zero or Pretty-Good Houses that have managed to strike a balance between sound energy efficiency and an attractive exterior design?

Some GBA articles have wrestled with this:

Banish These Details From Your Plans

Martin's Ten Rules of Roof Design

How Many Green Building Principles Are There?

Origami-Inspired Homes

Bronwyn Barry talks about "Boxy But Beautiful."

In General questions | Asked By Pat Kiernan | Jun 12 17
4 Answers

Why am I supposed to seal ventilation baffles?

One reason for venting a roof (in addition to keeping the sheathing cold) is to release moisture from the attic. Given that (and assuming it is a given) I'm a bit unclear on the benefit of air-sealing ventilation baffles, particularly in a cathedral ceiling application where the baffles are continuous from soffit to ridge.

In Energy efficiency and durability | Asked By Christopher Wegscheid | Jun 15 17
4 Answers

Adding exterior insulation to 100 yr old house - added risk for rot where framing contacts foundation?

Going to add exterior insulation (spray foam likely) over 1 layer of siding. The house has a rubble foundation with no capillary break between the foundation and the framing. The ends of the floor joists are embedded in the foundation.

The house had 2 layers of siding. I've removed the outer layer to expose the inner and found the inner siding and sheathing rotted at the bottom of the wall where it covered the band joist and sill. See pictures. Luckily, the joist itself is in good shape.

In GBA Pro help | Asked By TIM LANGE | Jun 14 17
4 Answers

How do I seal the slab edge in my basement around Stego Wrap and foam?

My basement slab has been poured, and I'm ready to cut back the Stego Wrap and 1/2" foam at the perimeter of the slab.

Is there a durable, low VOC sealant that would be ideal for filling the gap between the Stego Wrap and basement wall?

After this edge is sealed, is there a good way to dress this area up? Is there a specific kind of moulding that would nicely cover this slab/wall connection without taking up too much space? The only finish on the concrete walls will be primer and paint, no drywall, and for the floor probably only a sealer.

In Green building techniques | Asked By Eric Whetzel | Jun 13 17
3 Answers

Sub Basement Crawl Space

In the planning stage for steep slope home in North Carolina. After the topo survey results came in today, it is obvious we will need a crawl space under the lower level(will have main floor, lower level, then crawl space below due to steepness of lot). The foundation will step down on the sides. The way the builder describes it, they generally leave dirt floors, then encapsulate and condition this space and spray foam the walls. Seems to me I would rather treat this crawl like a mini-basement.

In Green building techniques | Asked By Kevin Spellman | Jun 14 17
1 Answer

Where should I caulk the exterior of these windows?

The thin-coat plaster blistered up through the paint just below the window apron in our 1938 house. I removed the loose plaster and patched and repainted an area of about 2 square inches. The bulging plaster seemed quite dry despite recent rains. I'm guessing the damage was due to rain, perhaps wind-driven rain. Climate zone is 6A if that matters.

There's no caulk between the aluminum wrapped window and the stone sill below it. Should I caulk it, or might that block drainage? The stone sill slopes, which isn't obvious from the picture.

In General questions | Asked By Jonathan Beers | Jun 14 17
4 Answers

Airtight Drywall vs Airtight Exterior

Hey all.

I read the post here: http://www.greenbuildingadvisor.com/articles/dept/green-building-blog/ho...

It's now a couple years old. I still hear of Air Tight Drywall frequently on here and other sites.

What on earth is the purpose of sealing drywall corners and joints with foam and caulking when you have to mud all these joints, corners, seams, etc. prior to priming and painting the drywall?

In Green building techniques | Asked By Nicholas C | Jun 14 17
2 Answers

Double stud wall details

We are in Minnesota (Zone 6a). 2200 sq/ft single level (9' walls), slab on grade.

I can't seem to find much information one way or the other about 2 particular details of a double stud wall. Thoughts?

1. What are the advantages and disadvantages to put the studs in line with each other or to stagger them?

2. What are the advantages and disadvantages to build them 24" OC or 16" OC?

In Green building techniques | Asked By Scott K | Jun 13 17
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