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1 Answer

Rammed Earth Soil Suitability


I have two soil samples both of them have 30% gravel when tested by wet sieving. When sieved with 4mm mesh, the small size gravel was 17.5 % (for both the samples). One sample has very little clay that forms weak thread and a small ribbon with difficulty. I have made test blocks with 5% cement and I plan to test the compressive strength in a lab.

I would like to know if I need more clay and, if the compressive strength works out, is it OK to build with the soil?

Thank you.

In Green building techniques | Asked By user-7108812 | Jul 8 18
4 Answers

How do I fix condensation between ceiling and closed cell spray foam insulation?

I have cathedral ceilings on my second floor with close-cell spray foam insulation on the bottom of my roof. There is only about a 1-2 inch gap between my ceiling and my "hot roof." I had the roof done 4 years ago and it is completely covered with ice and water shield. Over the past few months (covering the spring and summer), I have noticed water stains and mineral effervescence pushing through the paint on the very highest point of my ceiling. I have asked the contractor to remove the top 3 layers of shingles to see if there was anything wrong with the exterior.

In Energy efficiency and durability | Asked By MartyBiz | Jul 9 18
5 Answers

Insulation on hollow cinder block foundation wall

Hello, the lower level of my house is slab with about 4ft of block foundation wall and then regular wood framing above. I'm remodeling it and decided to frame out the block wall with 2x4 to add in electrical and insulation to the block wall on the inside. (it was originally framed with furring strips and drywall.)

In General questions | Asked By obg8 | Jun 30 18
3 Answers

We are completing construction of a 1½ story house in Hanover, N.H.

We are completing construction of a 1½ story house in Hanover NH. There is an unfinished “bonus” room over the 3 car garage. It has multiple windows. The plan is to someday convert this to a mother-in-law quarters. Currently, there is no ventilation, and no heating or cooling. Last winter icicles formed from the rafters, and one of the workers mentioned that there was some moisture (dripping from roof) on hot humid days this summer. We are concerned that the extreme temperatures will cause damage because of the water accumulation in the room.

In General questions | Asked By Frank Torti | Jul 8 18
5 Answers

Can this retrofit follow Lstiburek’s 4th rule for venting roofs?


- zone 6a in southeast WI
- 1978 prefabricated double-wide, raised ranch
- 2x4 framing, including roof trusses
- vented roof with continuous soffit vents and a ridge vent

I'd like to retrofit according to Martin's "pretty good house manifesto." I've demo'd a room to see what I have to work with (see photo). I can't figure out how I'll be able to conform to Lstiburek's rule that there should be more insulation on top of the wall than inside it. Particularly since I'd like to add an attic vent like AccuVent.

In GBA Pro help | Asked By user-7047201 | Jul 8 18
6 Answers

Would redoing the roof earlier than planned change insulation advice and be cost effective overall?

Zone 5/6 line in small NH town with no code officials. Retrofit for 1820 two-story Cape 1-story kitchen/dining sandwiched between main house and two-story attached barn that is ¾ converted to living space, ¼ garage (garage poorly insulated with sliding barn door that leaks to air and critters). Granite/rubble foundation, poured concrete floor with good drains but bulk water ingress in the springtime, so planning gutters and likely interior drain on uphill side and sump also to mitigate radon.

In Energy efficiency and durability | Asked By Theresa Swanick | Jul 5 18
9 Answers

VOCs and SVOCs: What do we know?

So a video published today discusses a topic I've been thinking about for a while. I'm going to be building our new house soon and the topic of indoor air quality and VOCs is something I've had on my mind but have yet to research fully.

In this new video, Matt Risinger and Corbett Lunsford discuss VOCs and SVOCs:


In Green products and materials | Asked By Lance Peters | Jun 29 18
2 Answers

Like to replace existing antique 3 tube and fin radiators in my old house but I'm not sure how many BTU's per foot they produce.

Attachment shows 2 tube, 3 tube, and 4 tube (I'm not even sure what this style is called). I have the 3 tube arrangement throughout the house and I would like to be confident that when I upgrade, I'm getting more heat for each room in this 1650, modestly insulated, house.

In Energy efficiency and durability | Asked By JamesRMillar | Jul 5 18
2 Answers

Mini split head placement

I want to put a 24,000 BTU mini split into a single story structure that measures about 36 X 24. It is divided into one long space and three bedrooms across the back. I know I won't get anything into the BRs without open doors but the simplest location is on one of the narrow end walls in the main area. My question is whether the unit will adequately condition the whole space or if the localized feedback from the one end will control temps and the far end won't get cool. Or is it small enough that with the air movement I don't need to worry?

In Mechanicals | Asked By DavidAtAshby | Jul 6 18
3 Answers

Trane XV18 heat pump: How low does it modulate?

Anybody know how low the Train XV18 heat pumps can modulate, in both cooling mode and heating mode?

I'm specifically interested in the 2-ton model.

Also, anybody know the max heating capacity at 17 F?

The info is very easy to find for Carrier variable speed heat pumps, but I can't find anything from Trane itself detailing the specs of Trane's variable speed heat pumps.


In Mechanicals | Asked By Aun Safe | Jul 1 18
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