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8 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
2 Answers

Replacement boiler sizing based on past usage

I'm looking for some reassurance and validation before I pull the trigger on an expensive purchase.

I currently have a 40+ year old, 137,000 BTUh oil boiler that is getting long in the tooth due to substantial corrosion. I have done many efficiency upgrades to my home. I am very interested in replacing the boiler with an electric boiler as the boiler I have now short cycles since I have improved the efficiency of the home so much.

Asked By Efficiency Fan | Mar 23 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
16 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
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
3 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
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
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