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15 Answers


I am obsessing over which pex to use for a whole house manifold installation. The choices are pex-a (uponor) vs pex b (viega).

Uponor seems easier to work with, less kinking, better flow etc.

What I am most concerned with is:

1.longevity (this is my forever house)
2. safety (leaching of chemicals into drinking water)

I am on a well.

Any input as to the longevity and safety of these two different types of pipes?


Asked By Dean Sandbo | May 26 16
4 Answers

Marathon and a heat pump water heater

Planning on Installing a heat pump water heater 80 gal rheem. and dumping it into two marathon water heaters... 50 gallon each. One of the marathons would be right next to the heat pump the other 80 feet away. Big long house.... The one 80 feet away would feed 1 1/2 baths, kitchen sink, dishwasher, washing machine, and potentially outdoor shower...

I know there will be about a gallon and a half sitting in that 3/4 line.. Essentially I am preheating the water going into the marathon...

Here is the question.

Asked By dean sandbo | May 27 16
6 Answers

Insulation around basement drain pipe?

We are buying a new house with a basement that we'd like to finish. We are in climate zone 4A, and there are no moisture problems in the basement. The floor cracks in the picture are (reportedly) from 6 years ago when the sump pump failed. We will be installing a backup pump.

Asked By Daniel Ems | May 25 16
1 Answer

Roofing / snow & ice safety / uninsulated in zone 5-6

I'm working on a house on the edge between Zone 5/6. It is uninsulated and sadly its going to stay that way.

It also needs a new roof, and that's not optional.

Of course it will keep getting ice dams and large icicles (boo hiss).

My question has to do falling snow & ice. The main roof is a hip. So falling snow/ice raises two issues.

1. Front and back porch already take a beating from above. I can see how the shingles fared (maybe halved their lifespan) How does metal hold up in these situations?

Asked By Mark Baker | May 24 16
12 Answers

Flashing "innie" windows - tape, caulk, anything at all?

Hi everybody! My builder friend and I are uncertain whether or not we are making mountains out of molehills here, and were hoping to get some feedback on a flashing detail.

This project has a thick wall buildout and "innie" windows: the nailing flange of each window is on the same plane as the house wrap, with exterior insulation and strapping/siding on top of that.

Asked By Benjamin Wooten | May 9 16
11 Answers

Paint choices


Asked By Lucyna de Barbaro | Mar 5 16
15 Answers

How to vent a flat roof

Designing a home in Santa Fe, NM. Roof will be TPO over open web trusses. Pitch is 1/4" / ft.
Parapets all around. Insulation will be blown-in cellulose. R value to be 50. How do I vent the roof cavity above the insulation? I could use mushroom caps. I've done the calculations and I need quite a few. How much air space is required above the insulation? 2", 3" or more? Also planning on installing a radiant barrier between the tops of the trusses and the sheathing. When I build crickets over the sheathing will I need to provide air ventilation for the cavity? Thanks!

Asked By jack robinson | May 14 16
1 Answer

Efficient house build blogs that I'm not following?

Hi all,

Besides the houses blogged about here at Green Building Advisor, what other house build blogs can you recommend? Particularly interesting in blogs about pursuing net zero, superinsulation, energy-efficient remodels, and all the passivhaus/passive house stuff.

Thanks in advance!

Asked By Matt Gauger | May 21 16
5 Answers

Exterior paint: linseed oil or latex?


I'm repainting my old farmhouse, which tends to have peeling paint issues. (1859s balloon framing with clapboards, wall repainted five years ago is starting to peel).

I've read a lot about Albeck and other linseed paints. I didn't see much here about these alternative paints.

Does anyone have thoughts about what the best options are for exterior paint?

I'm in zone 5 mid coast Maine.

Thanks for your help,


Asked By Ilmari Polojarvi | May 21 16
4 Answers

Backup power--generator vs. ???

Working on a project where the owner would like a 20-kilowatt whole-house propane generator. Due to a variety of factors, it's difficult to locate a unit of this size on their site, so I'm wondering now about other options for backup power. The primary issues they've raised are lack of water (they're on a well, so no power = no water), loss of refrigerated and frozen foods, loss of communications, and lastly, loss of heating. Their house has a propane boiler and electric circulators, so only minimal power is needed to keep the heat on.

Asked By David Meiland | May 20 16
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