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2 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
4 Answers

Insulating floor of an old barn

I have an 1804 bank barn and plan to use the lower level as a shop. Since dirt falls through the floorboards above anytime I walk upstairs, I need to think about insulating as a first step.

The easy thing would be to spray open-cell foam on the ceiling (bottom of 1.5" floorboards); but, I'm concerned that the foam won't maintain an air seal when people and machinery move around upstairs.

Asked By Michael Stelts | Mar 22 17
11 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
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
13 Answers

Hydronic Heating System Hydraulic Buffer Tank vs Hydraulic Seperator

This question might be more appropriate in a plumbing forum but I have had such great and thoughtful responses in the GBA forums I look to here first. This is also a hydronic heating mainstream topic which should be appropriate for GBA.

Asked By Roger Smith | Feb 26 17
5 Answers

Ideas for this floorplan Pt. II

....and I'm back! The system wouldn't let me reply to my own thread. It kept marking my reply as spam.

It's been a while since I posted an update to my thread but here it is.

I have processed all of the feedback given to me and applied this to my original wants. The idea is an open plan, living areas to the south, concentrate plumbing in one area, large master with walk-in shower, tub, master bed with walk-in closet, large kitchen, et cetera and this is where I am. I moved the master closet back up to the north wall again and I've added lots of other closet spaces.

Asked By Drew Baden | Dec 14 16
2 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
3 Answers

FPSF: Wing insulation with sub-slab insulation

Hi,

For a frost protected shallow foundation, I was wondering whether folks who use sub-slab insulation also like to include wing insulation? Code doesn't require both.

I would expect that the wing insulation raises the temperature of the soil under the edge of the slab toward the deep soil temperature. This ought to have an impact on energy loss through the bottom of the slab, but is it significant?

Are there any studies that show the thermal gradient under an insulated slab, and how it's affected by the addition of wing insulation?

--John

Asked By John Ranson | Mar 23 17
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