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14 Answers

HVAC ducting - Climate Zone 7a

The house is 40 year old bungalow with heated basement. It has an older 80% efficiency forced air natural gas furnace with an input BTU/hr 88,000 and output BTU/hr 71,000 with 1400 CFM.

The living room is 268 sqft and is ~24% of the total volume of the main floor, which is open plan so it is connected to the dining room (268 srft) and kitchen (137 sqft), each being ~12% of tot vol, respectively. The living room is at grade level with 9.3' high ceilings, compared to the rest of the main floor that has 8' height ceilings and is ~2' above grade.

Asked By user-6759891 | Mar 19 17
7 Answers

Is there any reason to think XPS at the big box stores would be of a lesser quality than what is sold at lumber/supply houses?

I'm getting ready to demo and redo my basement and plan on air sealing the concrete wall, sills and band joist. I generally try not to purchase stuff from big box stores as I find their quality to be questionable. But if XPS is the same regardless of where it's sold than cost becomes the primary variable. That's where the big box stores do win out. Thanks.

Asked By adam stanton | Mar 24 17
4 Answers

Building a new house, looking for opinion on insulation/exterior foam combinations

I am currently in the process of designing a new home. I built one four years ago that we have decided is too big and inefficient for what we need. This time around I am looking to build small, simple and efficient. The house will most likely be framed with 2x6 walls, however I would like to maximize R value of that wall.

Asked By user-6801629 | Mar 23 17
9 Answers

Building a house in Greenville, SC — insulation and air sealing questions

Building a house later this year. Plan to live in the home 30+ years. So I'm interested in the "long term."

The House: 3,350sf above grade. Very very little shade on this house. Kinda like building in the middle of a field. Lots of sunshine bearing down. Galvalume metal roof with 3/4" strapping between metal and synthetic felt (TBD). Zip System for exterior walls. 2x6 exterior walls. I'm planning on ponying up for the super efficient Trane XV20i heat pump. Cement fiber siding painted white.

The Plan:
Foam attic with open cell to 5.5-6".

Asked By Farm House | Mar 15 17
4 Answers

Closed-cell spray foam — Basement insulation concerns

Hi everyone, any insight you can provide is much appreciated.

I am currently preparing to install spray foam (4in of 2lb closed cell) in my basement.
The plan is to insulate the full basement walls (concrete + pony wall section), plus the sill plate and rim joist pockets.

A couple of questions/concerns I had prior to going ahead with the install..

Asked By user-6803198 | Mar 23 17
7 Answers

12v dc voltage system to run "micro sized" hydronic heating system

Hi Folks

My name is Bill and i would like to heat a small sleeping area in a mobile off the grid environment hydronically.

there are two ways i think may work but thought i would ask the more experienced group here to get some direction...

1st thought is to source a 12v controller that could run a 12v 4 way mix valve and also a very small 12v circulation pump to circulate water at a rate of less than .25 GPM

Asked By freewillieklr | Mar 23 17
15 Answers

Ice dam woes

Gents, I am an Electrical Engineer by profession. Your site is awesome, thanks... it is a shame that the home design and building industry can't incorporate this stuff so that homes are done right the first time around. Sorry... preaching to the choir.

We purchased a 2 year old home that we had inspected prior to purchase. The inspector either was ignorant of the issues in the attic or didn't look at all.

Asked By mg6467 | Mar 14 17
10 Answers

Sealing PEX and PVC pipe penetrations

I am reposting this to the Code section; not getting an answer in General Questions.

What do I use to meet code-required fire blocking and good weatherizing/air sealing for the circumferential individual tube/pipe and ganged tubes (a cluster of tubes), penetration gaps for PEX-to-wood (and plywood) and PEX-to-PVC pipe, and for PVC-to-wood, and PVC- & PEX-to-drywall?

With manifold distribution and multiple zoning of (1) HW heating supply and return (wall hung rads), and (2) potable water supply, there are a lot of penetration points.

Asked By Oak Orchard | Feb 27 13
7 Answers

Tankless water heater AFTER my tank?

I have a Rheem Marathon and do not want to replace it. However, we occasionally run out of hot water when we have company. This is rare, but inconvenient. Here is my quandry:

Asked By Emil Mackey | Mar 21 17
12 Answers

Metal siding — window head flashing detail

OK this keeps resurfacing so I thought I would see what others have come up with. When using metal siding (corrugated or sim.) dealing with the window head always seems to be a bit of a conundrum.Typically I see a piece of "J" flash utilized. But this usually points up, which may conceal the cut of the cladding panel, but consequently also catches water. Seems wrong. I have been trying to come up with an alternative and drew the attached, but surely someone more intelligent than I must have devised a better solution for this issue ?

Asked By Erik Lobeck | Mar 21 17
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