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10 Answers

Smart MemBrain with mineral wool

Using Thermafiber Mineral Wool in 2x6 stud cavities. Planning on using CertainTeed's Smart Membrain before hanging drywall.

1.) Is this the best idea in terms of proper product use and installation?

2.) Will stapling the Membrain to my studs cause any issue?

Asked By Nicholas C | Oct 18 17
12 Answers

Hundreds of flies in my bags of Roxul insulation. Is this a concern?


I stored my brand new roxul insulation ( still in wrapping) in the barn and has been sitting on a raised shelf for six months. I go to open all the bags to insulate today and there are hundreds of flies inside the bag, and alive. It's almost like they were all drunk (I assume from the insulation smell). My donkeys use this barn and the barn has a lot of flies in general.

Asked By Tom87 | Oct 17 17
3 Answers

Seal foam attic baffles at kneewall

I am installing the foam version of the attic ventilation baffle at my kneewalls so that I can blow in a good amount of cellulose. The online video from the manufacturer shows them simply hammer-stapling these along the trusses. Two things I notice, 1.) These things rattle like nothing else when air is coming from my vented soffit at the right speed/angle because there is nothing pinning these tight to the underside of my roof's OSB (ideally I'll have enough insulation to keep them somewhat tight) but I don't think it'll be *that* deep.

Asked By Nicholas C | Oct 13 17
14 Answers

Who has a favorite heat-pump water heater?

We are now underway with our "pretty good" house here in southern Oregon and I am committed to the hybrid heat pump water heater concept for our 2100 sq ft, three generation house. With four adults and a grandchild in the house, I felt that an 80 gallon unit would be desirable. We plan to locate the HPWH in a centrally located laundry room which is just under 700 cubic feet and have plumbed a floor drain into that room for condensate or tank failure (hope NOT). I had been inclined to go with the GE GeoSpring but I have heard a rumor that GE is going to discontinue manufacture.

Asked By Alan Hart-McArthur | Oct 13 16
13 Answers

Is using phase change insulation with ductless minisplits the perfect marriage?

I'm interested in using phase change material with a ductless minisplit heatpump - they seem like the perfect combination. (Also, the phase-change insulation discussion on this site are pushing a decade old and I'm hoping for a refresh.) There seems to be several people selling phase change insulation materials now including - and - claiming a 25-35% HVAC reduction.

Asked By Patrick Freeburger | Oct 10 17
12 Answers

Non-toxic ductwork

We are researching truly non-toxic ductwork for our all new electric heating/cooling... HVAC system. We are only finding the usual hardpipe which is known to be coated on inside with rust proofing, and the flex. The flex is found to be polyester and nylon in the interior with a wrap of insulation, probably but we've not been able to find that info yet, probably has fire retardant and formaldehyde, and who knows what. then the outer black plastic layer or silver whichever, silver would be best as all plastics outgas toxic fumes and when heated... even moreso.

Asked By Evan&Suzy | Oct 2 17
0 Answers

A discussion on mildewcides and fungicides in paints.

Good afternoon all,

I am near the process of painting/staining my walls/ceiling/cabinets in my tiny house.

I will be getting low/no voc products but I wanted to see if anyone has any experience using a no-mildewcide paint and how it is holding up?

Some high quality, low voc paints such as Eco's and Safecoat have no mildewcides but I am wondering if the downsides of no-mildewcide paints end up becoming problematic.

Specifically, I am wondering:
1) if no mildewcide paints are ok for bathrooms (with steam from showers).

Asked By Grey Wolf | Oct 7 17
2 Answers

Brick sealer on a wall with exterior insulation

Hi all,

We are in the final stages of completing our Pretty Good House. We went with (from inside to outside...) 2x6 stud walls filled with damp blown cellulose, 2 layers of 1.5" polyiso rigid insulation, house wrap, air gap, brick.

The builder is suggesting we use a brick sealer (Siloxane) to help slow/stop the wicking of moisture into the brick.

Is there any problem with this? I could see where it could be a benefit if it truly seals the brick from absorbing water, but I also wonder about it preventing water that finds its way behind the brick from drying out.

Asked By Clay Whitenack | Sep 29 17
1 Answer

Barn wood siding durability


I'm an architect with a client who wants to use reclaimed barn wood siding for their house. I have now had two contractors tell me it is unreliable and "goes bad" (cups, loses integrity) fast. I have difficulty understanding how a product that has survived for 100 years can "go bad." I plan on treating it like a water screen, allowing for dimensional movement.
Does anyone have an opinion on this? Does anyone have particular nailing patterns that will help prevent cupping?
Alternatively, any faux barn siding that will work for exterior use, but still be sourced responsibly?

Asked By user-6914266 | Sep 27 17
4 Answers

Half Lite or No lite sliding patio door?

Wanted to know if anybody knows of any companies that would do a sliding door with half lite glass in it. Want to use the door for the exterior of the building. Also a patio door with a single half lite OX setup where the "O" is a solid panel and the "X" is a single half lite.

Asked By Dave R | Sep 25 17
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