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2 Answers

Best adhesive for Visqueen lapped to concrete block?

Looking for an adhesive to stick my 6 mil visqueen vapor barrier to the concrete block stem wall. I want to lap the visqueen up about 6 inches. I have tried duct mastic which sticks well to the block but readily peels from the visqueen. Something other than Tremco?

In General questions | Asked By Robert Holland | Apr 28 16
3 Answers

Hot water to toilet

Hi, I had this idea that I could purposely run the hot water to the toilets in the home to help heat the small bathrooms which by design have no supplemental heat source except a ceiling heat lamp on a timer. The homes are 900 sq.ft single heat source via direct vent gas wall heater (Rinai). My question is why not use a bit of hot water to heat up the toilet and create some extra heat for the bathroom and make a nice warm seat.

In General questions | Asked By MURRAY bANTING | Apr 28 16
2 Answers

Ways to cool in Hawaii

Hello, I'm in a zone-1 area, specifically, the Leeward side (hot dry!) of Oahu. My house was built in the 80's, has minimal to no insulation and none in the attic, and only has window-unit AC (mounted in the wall). I prefer not to use the AC when at all possible, but as the summer comes on, it ends up getting hotter inside than outside with a breeze despite having the windows and garage open.

In General questions | Asked By Josh Lavender | Apr 28 16
44 Answers

Inexpensive exterior insulation stand-off — Critiques?

I am trying to come up with some inexpensive, and sensible details to accommodate a 6" layer of exterior Roxul Comfortboard IS comprised of two layers of 3", 2' x 4' batts. See attached PDF for details. My concern is that with such a substantial thickness of Comfortboard, the potential for faster "sag" through this, or durability issues during seismic events is problematic. On many of our projects, we have screwed our vertical cedar 1x3 rain screen material directly through a single, thinner layer of the Comfortboard directly into the framing.

In Green building techniques | Asked By Burke Stoller | Apr 19 16
7 Answers

Why do I feel cold on my right side when I sit near my new windows?

I got triple-glazed windows installed, but I seem to feel cold on my right side of my leg sitting next to the new windows. Everything seems to be sealed.

Can someone give me a explanation, please?

In Energy efficiency and durability | Asked By Scott Brady | Apr 25 16
17 Answers

What's the payback?

I read here over and over again the recommendation that a house should be built tight and ventilated. The house should also have insulation levels over what is required and what is typically done. I'm good with that if it makes sense. I'm sure someone has done some studies in various climates and calculated the savings and the simple (or not so simple) payback for the upgrades, but I'm not finding it. What makes sense?

My case, climate zone 5, new 2000 SF home, cheap natural gas. No AC. Colorado, lots of sun. Conservative habits, turn off lights, keep tstat low.

In Energy efficiency and durability | Asked By Brad Haack | Apr 24 16
19 Answers

How would you spend $40,000?

Hi GreenBuildingAdvisor community - I've been reading off and on for the past 12 months as we gear up to build our home. It's simulatneously depressing and empowering to read through how much is required to properly build a home.

We're pretty happy with the plans (the ones I'm including are not quite the latest - we'll be adding a few windows and moving some interior walls around) but before we do the next round of changes - we need to make a decision about ICF or no ICF. It's a $40,000 question for us.

In Plans Review | Asked By Adam W | Apr 27 16
3 Answers

Minisplit design in new construction

Hello, I am in the process of designing my new home build. I have decided on a full ICF house with a goal of high energy efficiency. The house is 2300 sq ft main level living with a 2300 sq ft walkout basement. The home is ranch style 64x36 located in Colorado (Zone 5). I am currently having some hurdles with my HVAC system. I like the idea of doing mini splits in the main level with hydronic radiant heat in the basement slab. The manual J calculations I have done show 19k btu/h for the upstairs and 13k btu/hr for the basement.

In General questions | Asked By Kyler Massey | Apr 27 16
6 Answers

Insulating existing slab on grade - need for sleepers?

After completing a strategy for insulating my slab-on-grade floor (which sits on sand ONLY) as part of a major building renovation in Zone 5a, I discovered the GBA construction detail for the same situation here: http://www.greenbuildingadvisor.com/cad/detail/treated-2x4-sleepers-two-...

The GBA solution calls for treated lumber sleepers in each layer of insulation.
a) Given the high compressive strength of XPS, what purpose is served by the sleepers?

In Energy efficiency and durability | Asked By Dean McCracken | Apr 20 16
2 Answers

HRV intake below grade?

Is there any benefit to running X amount of pipe below frost grade to pre-heat/ cool intake air to an HRV? Would this not increase the operating performance of the HRV?

In Energy efficiency and durability | Asked By Kris Currie | Apr 26 16
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