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14 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
2 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
3 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
14 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
0 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
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
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