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8 Answers

Leaky Ductwork in Basement

After getting a very poorly rated energy audit from our electric company, I'm working diligently to get our house more air tight. Seeing lots of posts about HVAC equipment, I'm thinking ours is a little lacking. It is 5 years old, the furnace is 95% efficient. But, the black tape is falling off and according to infrared, it is leaking. I've attached several pictures and also infrared pictures. We are in zone 5 (NW MO). It is 20 degrees outside and our basement walls are 47 and 53 at the frost line.

In GBA Pro help | Asked By Becky Parrish | Feb 9 16
3 Answers

Appropriate treatment of shower/tub walls adjacent to dense-packed cellulose?

Climate zone 4C marine, planning for new construction.

Planned typical R-26 exterior wall section: fiber cement siding, 1X rainscreen furring, 3" 8pcf rock wool, taped sheathing (primary air control and WRB), 2X4 load-bearing wall with 3.5pcf cellulose, 1/2" gypsum board.

How should interior high-humidity areas like showers adjacent to this exterior wall section be handled?

In General questions | Asked By Stuart Friedberg | Feb 9 16
33 Answers

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

In Green products and materials | Asked By Carolyn Farrow | Feb 8 16
2 Answers

A couple of renovation questions regarding my 1960 Cape

Hello all, I was looking up information on housewrap, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to go about doing some renovations this spring/summer on my house

In General questions | Asked By Khouri Rice | Feb 9 16
2 Answers

How do I calculate the interior temperature of a window at a given outside temperature with a fixed interior temperature?

I am trying to predict at what outside temperature will I get condensation on my windows. If it is 70 degrees inside with 40% relative humidity and my window has a u-value of .3 at what outside temperature will the window (frame and center of glass) have condensation. How do I calculate this?

In GBA Pro help | Asked By Chaz Steffen | Feb 9 16
4 Answers

Homemade dog house insulated panels

I'm having to make a homemade dog house for my rather large Akbash mountain dog family (papa, mama and 12 wk old pup). I live in Region 5, western Colorado. I need a floor panel, roof panel, and 4 wall panels. I had this design for making the panels utilizing empty water bottles. What do you think? Will this work well enough to keep in heat and block outside cold air? I wish I had some idea of the R value. Cut 42" long x 36" tall 1/2" thick thick plywood panels. Glue 2x4s around inside edge of each wall panel perimeter, on the wide (4") side.

In Energy efficiency and durability | Asked By Andy Nels | Feb 7 16
5 Answers

Radon venting in 1/2" crushed rock?

I have about 9" of 1/2" crushed stone as a base for the slab (2" of foam will go between stone and slab). I searched for clean, no fines, and the best I was able to get is mediocre clean.

Will installing 4" perforated PVC pipe in this material still work as a radon vent?

Would the efficacy be improved if I backfilled the 8" deep x 8" wide trench for the pipe with 3/4" rock?

How long should the pipe be?

Thanks.

In GBA Pro help | Asked By David McNeely | Feb 9 16
7 Answers

Reducing noise transfer between rooms through ducts

In our current house which has all rigid metal ducts, noise transfers easily between rooms through the ductwork. For our new house, I want to make sure that the HRV ductwork does not have the same problem.

Flex is often maligned but it seems as though it could be useful in limited quantities. Based on what I read here, it seems that running a short section from the metal trunk to each room, while making sure the section is straight, pulled tight, and sized for the proper airflow (which probably makes this section upsized from the metal diameter), should not cause a problem.

In General questions | Asked By Nick Hall | Feb 2 16
1 Answer

Does a rainscreen assembly maintain the exterior surface of paint?

I am trying to argue for a rain screen assembly. Is there any evidence that would highlight extending the time between painting the exterior siding by using a rain screen?

In Energy efficiency and durability | Asked By Julie Klump | Feb 9 16
7 Answers

Using a second water heater as an indirect fired tank?

I have two water heaters. A 50 gallon HTP Phoenix Light Duty propane water heater, and a 50 gallon electric resistance water heater. The two heaters are plumbed in series, electric water heater first, then propane. To make a long story short, some things didn't work out as originally planned, and now I'm paying an extra $15-20/month (and wasting source energy) because I'm heating up a bunch of water with electric resistance right next to a high efficiency propane water heater.

I'd like to stop doing that. I have a couple of extra constraints:

In Mechanicals | Asked By Tim C | Feb 8 16
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