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0 Answers

Why your minisplit is likely not "modulating" at all

In other posts I've made observation of specified "capacity reduction" of several hyper heat like systems.
Those observations were all based specifications, which are all at 47f. I observed that most offer a 1/3 ratio. some offer a 1/9 or 1/10 ratio. I found this graph of constant speed capacity.
This dramatically alters how we must interpret the specification as outside temperature changes. !/3 capacity ratio @ 47f will maintain constant output. NO MODULATION.

In Energy efficiency and durability | Asked By Jerry Liebler | Jan 13 18
1 Answer

Air sealing an old brick building

I’ve been reading with interest the posts on weatherizing old brick buildings, but I still have some specific questions I hope someone can answer.
I have a circa 1837 brick federal with double wythe walls in central Vermont. The bricks are hard fired with tight mortar joints and moisture from the outside is relatively well controlled. Exterior walls are strapped with 5/4” planks supporting the lath and plaster. Interior walls are the same 5/4” planking with lath and plaster on both sides.

In GBA Pro help | Asked By duanegormanbuilder | Jan 13 18
19 Answers

Radiant basement floor as "redundant" heat source?

I'm building a " pretty good house" and as you know, from my other discussions,planning to heat with high performance mini split heat pump or pumps exclusively. With no back up heat I want REDUDANCY. I want to, in the event of a "partial" failure 1. First priority avoid "freeze-up" if it's unoccupied during a cold snap. 2. maintain a " livable but reduced IDT, in all or parts of the house. 3 have an efficient system .

In Energy efficiency and durability | Asked By Jerry Liebler | Jan 9 18
18 Answers

Multiple plumbing issues and water heater questions

Hi all,

I have a few issues surrounding my plumbing and hot water heater and the behavior of it and optimization of the system. I will use bullet points below because I am not certain that all of the issues are related, but want to get thoughts on each.

The components of the system are as follows on a 20 year old, ~6400 sq ft two level house.:

In General questions | Asked By John Sexton | Dec 22 17
3 Answers

I have a 1960 ranch home which has the plumbing for the bath, clothes washer, and water heater centrally located

I have a 1960 ranch home which has the plumbing for the bath, clothes washer, and water heater centrally located. In the summer when the temp outside reaches 95 to 100 degrees in Louisville KY, the bathroom has a 'sewer' smell. The hotter it gets the more I [can smell it].

I need some help with this as my daughter's bedroom is next to the bath so I have to close the door and put a towel at the bottom each evening before putting her to bed.

In General questions | Asked By Stanglover1 | Jan 2 18
6 Answers

Insulating curtains for a sliding glass door?

I have a large two-pane sliding glass door in my den (same room as my woodstove). While it provides nice views during our 10 hours of winter daylight, it just loses heat during the 14 hours of darkness. My IR gun indicates 10-15 degrees of temperature difference, compared to the exterior siding.

In Energy efficiency and durability | Asked By Tyler Davis | Jan 1 18
2 Answers

Power vent water heater is backfeeding cold air

Hi guys, We here in Michigan just got over a single digit 11 day cold spell. This is where you really can test your basement for cold air leaks. Speaking of that, I waked by my water tank and was pretty much blown back by a wave of cold air. So when the fan kicks on it pulls air from the basement to vent the gas out the rim joist through 2" pvc tube. Ok, that's great. Now when the fan is not blowing the pvc is just letting the cold outside air to backfeed right through the fan intake into the basement.

In Mechanicals | Asked By Mid Michigan | Jan 10 18
10 Answers

What materials meet code for "flash and batt" on my ceiling?

I have an unfinished basement and I am looking to add about 5" of insulation to fill up the joist bays on the ceiling. The bays are 7 inches deep and will soon have around 2" of foam.

I am wondering if I would be able to fill the bays with Roxul and cover the entire ceiling with house wrap.

The reason for the roxul is that if necessary it would still be possible to access what's in my ceiling (wiring and some pipes), without the negative effects on air quality of the fiberglass.

I understand I can trim the roxul with a knife to match my very uneven 80 year old ceiling joist bays.

In Energy efficiency and durability | Asked By user-6993560 | Jan 12 18
14 Answers

Region 5: above-grade renovation insulation improvements

Region 5, East Stroudsburg, PA 18301. Cape Cod style house (bedrooms on 2nd floor in what was once a large attic).

I'm renovating the kitchen on my first floor. I will be pulling down the drywall on the exterior wall and the ceiling.

In General questions | Asked By Ryan O'Rourke | Dec 18 17
6 Answers

Best hidden fastener system?

I am looking for siding profile to use with a wood siding hidden fastener rainscreen siding system.

I am installing on 4" exterior insulation.

I had initially liked the Climateshield profile until I learn you have to use z-girts on 4" insulation which seem like they'd cause thermal bridging and are more expensive than furring strips (this fastener requires no furring strips) - you can see more about z-girts here:


In Green products and materials | Asked By J M | Jan 12 18
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