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3 Answers

Pex size for hose bibs?

I have a very long ranch house...
All of my potable water has been plumbed with uponor manifolds 3/4 supply, 1/2 home runs to each fixture.. (two manifolds for each side of the house).

I want to run my hose bib's before my water softener.

the question I have is can I use the same method.. a home run of 3/4 pex... attached to a manifold with 1/2 off of that to multiple hose bibs?

I was planning on using woodford model 19's.

I imagine using 3/4 all the way would give me more volume at the hose bib..

In General questions | Asked By Dean Sandbo | Aug 21 16
51 Answers

Mooney floor

I want to put insulation on top of a concrete floor.
A layer of foam + plywood bolted to the concrete has been suggested. (By Dana I think)
While that looks an good option I've been exploring more low cost options.

What about a Mooney wall, flooring variation.
Thinking about 2x4 + 2x4, filled with blown in cellulose. Likely GreenFiber or InsulMax.

Is that a good alternative?

In Green building techniques | Asked By Tony Tibbar | Aug 6 16
5 Answers

Use foam "fluff" as attic insulation?

A facility near me apparently cuts up a lot of XPS foam and advertises the remains on craigslist for free. They have huge bags of about 4"x4"x1.5" chunks and others they refer to as "fluff". They're just very small, finely ground up pieces of the foam. Since this is free, I was wondering if the "fluff" could be used almost like cellulose in the attic or if the fact that it is no longer solid would greatly diminish its insulating abilities? Thanks for any advice.

In General questions | Asked By Ryan Cornelius | Aug 22 16
1 Answer

How far should poly run up the edge of a monolithic slab on grade?

How far should polyurethane run up the edge of a monolithic slab on grade? If it doesn't run all the way up (as I've seen in some details), should the edge be painted with damp-proofing?


In General questions | Asked By John Ranson | Aug 21 16
3 Answers

Cathedral ceiling vs. standard ceiling: Insulation issues

I'm building a 20x20 detached garage with a finished loft area. Loft area will have 2 foot knee walls and a 14/12 roof pitch to maximize space where I won't hit my head on the ceiling. I'm trying to decide whether the loft should just have a cathedral ceiling, or if I should add in framing for a standard 8' ceiling.

In General questions | Asked By Aun Safe | Aug 20 16
2 Answers

Adding a second story

Is adding a second story harder than a first?

In General questions | Asked By John Chavege | Aug 21 16
2 Answers

Spray foam in roof deck — Is lower R-value than minimum code recommendation OK?

I am remodeling a 106-year-old home in Climate Zone 4A where the minimum recommended attic value is R-38. A local spray foam contractor, with a large national company, told me that with spray foam a much lower R-value is OK. He quoted the job at R-20 for the roof deck. I know that air sealing is of paramount importance but it seems R-value also is important.

Is R-20 really enough?

In Green building techniques | Asked By Ross Williams | Aug 21 16
1 Answer

Unfaced XPS vs Foil-faced Polyiso for Rim Joists

Hi all

I'm looking to insulate my basement rim joists in the next few weeks, getting rid of the stuffed in fiberglass batts. I've done some research here and other places, and I'm kind of stuck trying to decide on material to use. Based on cost and material availability, I've narrowed it down to using 2" unfaced XPS or 2" foil-faced polyiso.

In General questions | Asked By Paul Jones | Aug 21 16
5 Answers

Mineral wool roof

We are in the beginning design phase of our new house. The current concept is a 1,600 sqft ranch with a 4/12 pitch shed roof to allow clerestory windows along the south side. We are in the middle of Iowa, on the edge between climate zone 5 and 6.

The single roof plane would be a cathedral roof with both interior and exterior insulation. No valleys, no skylights, no dormers, no can lights, just a single roof plane with fascia mounted vents at the top and bottom.

In Energy efficiency and durability | Asked By Ben Woline | Jun 3 16
3 Answers

Central Fan vs. HRV

Hi all another question.

Background: I live in Minnesota (6B on the climate map) and I have a 3 year old house with bath fan exhaust only. There are 3 bath fans on the second floor that run constantly. House is about 3800 sqft now and will be almost 5000 sqft when basement is finished. We have been running the furnace fan constantly recently to keep the house even in comfort, I'm experimenting with "circulate" vs. always-on. Furnace is high efficiency but with an old school motor, not ECM. I don't see us proactively changing the furnace in the near term.

In Mechanicals | Asked By Ben H | Aug 20 16
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