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3 Answers

Insulate ducts in conditioned basement?

I have been air sealing my ducts as best I can with mastic. I now have the first 4 feet or so of supply duct from the furnace sweating pretty good whenever it's on. This is all in the basement, which we use as another family room like area, don't use it as much as the first and second floor, but a fair amount.

In the summer it's freezing with the air conditioning on and the ducts sweat for a few feet, as mentioned.

In the winter, however, it's still a little chilly, certainly not overly warm.

Asked By Jeremy M | Jul 27 15
32 Answers

More confused....open vs. closed spray foam for my climate zone

Hi,

I want to finish off my third floor. My house is in Richmond, VA - Climate Zone 4 - (right in the middle of the zone). House was built in 1993. The attic is walk up and rafter built with 2x8s. Here are some pics of the space:

Asked By Joe Watson | Jul 21 15
9 Answers

We were looking to replace our front door which has 2 flanking sidelights

The door appears original to the house which was built in late 1890s (all glass is single-pane and the door has no weatherstripping). Needless to say, it's very drafty (we use rope caulk to seal gaps and plastic to cover windows in winter).

We've had 3 estimates for the work, all ranging between $3,000-$5,000 bucks. All contractors cite unknown condition of framing, subfloor, etc.

Asked By Christian Rodriguez | Jul 27 15
2 Answers

How to better insulate my roof

I have a log home with a high ceiling. It has 2by 12 roof rafters. Which means I have 10inches of insulation. I live in northern NY. I want to know if I put 2inch foam panels and a metal roof will it increase my r rating? I seem to lose a lot of heat through the ceiling and it's very hot in the summer.

Asked By Rodney Coryer | Jul 26 15
2 Answers

Flat roof insulation

Here is the Chicago area.
If I can't ventilate the flat roof, then what happens?
what if I am using the fiber insulation and radiant barrier together..?

Asked By Mansig Yoon | Jul 26 15
5 Answers

Closed-cell foam in a 65-year-old Cape Cod roof?

We recently removed all of the vinyl siding and homasote from our cape. We installed R15 fiberglass in the walls - there was not insulation previous to this, just homasote. In addition, we replaced all of the windows with double glazed argon gas filled low E windows.

Asked By Michael Boice | Jul 24 15
34 Answers

It's 2015 and they still build like this...

Brand new build going up in Phoenix, AZ. What you see is completely 100% framed and ready for stucco. The missing OSB sheathing is done on purpose. They do "open framing" and only use sheathing where required. The rest is open 2x4 framing.

They will stuff R-13 batts within the 2x4 walls, staple on some building paper and then put 1" of rigid EPS on the outside and use conventional stucco to finish it off.

A recent blower door test on a home like this showed 15 air changes per hour.

ALL of the duct work and air handlers are installed in the 150F unconditioned attic.

Asked By Peter L | Jul 1 15
2 Answers

Another solar pumping question

Hey there,
I would like to use solar power to pump around 10.000 L of water/day from a well into a reservoir that I could use for gravity fed irrigation via a drip system. Please give me your thoughts on this, I would like to know if it's doable. I'm a newbie so please bare with me if I ask something outrageous
The specs on the pump:
At 45 volts DC the peak efficiency point is 18 GPM at 45 feet of head..
Max Current: 8.5 Amps
Max Power: 380 Watts
My question is:
Is it possible to run this pump directly from solar panels with an LCB? Would 2 x 250W panels wired in series do the job?

Asked By lee alice | Jul 24 15
4 Answers

Best practice/advice- Three insulation assemblies

I need guidance/advice on insulating three separate assemblies as I finish the space on the 2nd floor of our 1952 Cape Cod.

The space: Total 2nd floor square footage equals 960- all conditioned space
No dormers on the front, single shed dormer spans nearly the entire backside of the house.
Williamsburg VA- Climate Zone 4A- more hot & humid than you might imagine.

Here is what we are starting with:

1. Exterior wall on either end (facing North & South) is constructed as follows- Brick, 1" airspace, #15 felt, 1/2" insulating (asbestos?) sheathing, 2x4 studs

Asked By Chris Kolloff | Jul 24 15
6 Answers

How can I upgrade the insulation in my walls?

Walls in my mobile home only have R-10
All values:
walls U .097 R-10.3
ceiling U .038 R-26.3
Floor U .048 R-20.8

I live in a mobile home designed for New Orleans (Katrina, FEMA trailer) yet I live in northeast Maryland (Elkton, MD). The minimum for new construction (based on my zip code) is R-13 and EnergyStar dictates R-20 (15 cavity + 5 sheathing).

Asked By Vincent Dipietro | Jul 20 15
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