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2 Answers

hot water recirc loop with pex homerun system

Has anyone played with the idea of doing a hot water recirculation loop with a pex manifold homerun system?

My desire for a recirc loop is mostly inspired by Gary Klein and my reading/watching of his work. Although he doesn't recommend a home run system because you can't recirculate hot water.... well, I think it might be possible. Maybe I'll sound crazy here, but what can I say, I love systems design.

I see this as 2 issues:

1. Is it doable?

Asked By Jamie B | Feb 17 18
8 Answers

Hi, I'm performing an energy retrofit

Hi, I'm performing an energy retrofit. My house has tiny roof overhangs and will have none after external wall insulation is applied. An unvented attic with internal spray foam and/or external rigid insulation is too expensive. I've found a product called....

My house is in Detroit (zone 5a).

Asked By Thrifttrust | Nov 2 17
9 Answers

I am looking at building a slab-on-grade house

I am looking at building a slab-on-grade house. I am also trying to avoid having any ductwork (or other utilities) in my attic. Where is the best place to route ductwork, plumbing, electrical, and sewer if I am slab on grade?

I wish to avoid a basement or crawlspace and their associated challenges. I also want to have the ceiling free of penetrations and no ductwork in the attic. Is it OK to run plumbing/sewer/electrical conduit under a foundation slab? I already know I want to avoid running ductwork under the slab, so I'm considering a ducted minisplit with minimal ductwork.

Asked By JB487 | Feb 15 18
10 Answers

Rigid insulation beneath floor on shed


First time posting and would like to thank you in advance for at least taking the time to read this.

I am building an insulated shed/writing studio for my wife. Looking to make it 12'x8' and was thinking of building it on concrete blocks with 2"x6" studs for the bottom frame. On top of that I was planning on 2" rigid insulation followed by plywood then flooring. Will I be able to put the sill plate on top of this and drill through to the 2"x6"'s? I haven't worked with rigid in this context before.

Putting it on blocks seems the best option in case we wish to move it later.

Asked By Allan Manley | Jun 22 17
9 Answers

Fastening details - deck ledger to insulated slab

I am designing an insulated Monolithic Slab. I plan to install 4" of Roxul comfort board beneath and around the perimeter of the slab.

Does anyone have experience attaching a deck ledger to a slab (or stem wall) that is insulated with Roxul? Or is it advisable to place a higher density product beneath the ledger to avoid compression which may happen with the Roxul Comfortboard?

What type of fasteners are recommended for this application? Would a standard wedge type concrete fastener like a red head work?

Other solutions?

Asked By Michael Iacona | May 19 16
6 Answers

Corrugated metal over mineral wool

Hi, I am looking for ideas for installing vertical corrugated metal over Roxul comfort board.

A bit more about the project:
Zone 5B,
2x6 @ 24" OC walls insulated with Roxul batts (R-23),
plywood, wrb, and
2" Roxul Comfortboard (R-8), corrugated metal siding running vertically.

Do I need to install vertical furring a layer of horizontal furring to attach the corrugated panels to? Can the metal be attached directly over the comfortboard?

Thanks for any thoughts/ ideas.

Asked By Stacey V | Feb 6 18
20 Answers

Basement insulation

Hi! I appreciate all the forum advice I get from your organization. I am seeking to take over my Dad's residential construction business and I am designing my own house which we will build in a few years. I am in college to do so and am learning an awful lot. For basement insulation, I narrowed down some ideas that I would like to go with. To let you know some of our practices, we dampproof our basements and run drains around the perimeter just in case. As for the insulation, upon much research, I have found that it is best to use sub-slab insulation. We live on the southern edge of Zone 5.

Asked By Golfm02 | Feb 12 18
5 Answers

Is foamboard and stucco to the ground in a pier and beam house a termite risk?

SUMMARY: I'm contemplating installing foamboard + stucco over existing wood siding, running it all the way to the ground on my pier & beam house, but worry whether this could invite termites.

Asked By Michael Bluejay | Feb 12 18
10 Answers

Thoughts on adding rigid insulation over existing siding.

We have a historic house that is undergoing a deep energy retrofit with rigid insulation being applied to the outside and then strapping and new siding. The contractor has ripped off a few layers of asphalt siding and is now down to the original siding. He would like to keep it on and simply put the new rigid insulation over the siding. It seems this will create some nice air pockets which be good insulators, and be a cavity for drying if needed. Does anyone have experience doing this and any input on pros and cons versus taking that original siding off and going down to sheathing?

Asked By Phil Kaplan | Oct 19 11
5 Answers

Cathedral roof, unvented, rigid foam

Hey GBA,

I've been reading several articles on the merits of Vented/Unvented cathedral ceilings. I'm about to build an energy efficient home in a mountainous zone 6 with lots of potential snow load. I'm trying to get R-30 on the walls and R-60 on the roof. Our climate is quite dry and I assume most of the vapor pressure will be from inside to outside in winter.

Asked By Steve Mackay | Feb 9 18
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