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8 Answers

Porch posts

We are building a wrap around porch that extends 6'. Since we know, because of code we have to use 6x6 for the posts for the deck, I have question about the posts that supper the roof.

One way is to use the same 6x6 and extend it from footer to header. We think that since these posts will be 6' apart going around the porch it might seem a bit too bulky.

Does code allow you to replace 6x6 posts with a PVC reinforced porch posts (they are turned and look like traditional porch posts)? Or do we have to stick with 6x6 lumber?

In Building Code Questions | Asked By Matt Cibula | Mar 25 15
9 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

In PassivHaus | Asked By Gerald Blycker | Nov 21 14
3 Answers

Manual J - Calcs - Mini Splits

Zone 4B - 3,300 sqft - 2 story - R10/R25/R60 with R8 windows - open floor plan design

The calcs came in at 3.25 tons heating/cooling. Two ductless minis per floor:
3 - 9,000 Btu Mitsubishi Hyper Heat Pumps - 26 SEER - 10.5 HSPF
1 - 12,000 Btu Mitsubishi Hyper Heat Pump - 26 SEER 10.5 HSPF

$12,000 installed (P&L) for all units - 10 year warranty

In Mechanicals | Asked By Peter L | Mar 26 15
4 Answers

Insulating truss joists 16" on center — Best way?

Batt insulation for 24" o.c. The 2x lumber is 23" wide. The truss joists I'm looking at are 2x4 lumber 24" o.c. The space between the trusses is 21.5". Does anyone know if R-19 batts are available in 21.5 or 22"? Seems like squeezing a 23" wide batt will not work well.

Also the tiger wires used on 2x lumber will not work well on a truss. Is there another method of holding the batts up to the floor?

In Energy efficiency and durability | Asked By Walter Gayeski | Mar 25 15
7 Answers

Evaluating feasibility of solar panels in site rated at 895 (or 65% TSRF)

Just got a quote from solar panel install company and thinking I may skip solar and redirect funds to doing more insulation work on the house. But before I do that, I wanted to run some thoughts by here.

1. I am calculating that per kW I will be at $4.25 installed (I am in Boston area). Considering article I just saw today on GBA pegging average installed price $0.80 less per kW I am discouraged.

In Energy efficiency and durability | Asked By Apollo S | Mar 25 15
6 Answers

Strapping material for rainscreen...plywood fir or spruce?

I'm ready to put the strapping on-top of my WRB, only I'm not sure what the best choice is.

I want a 3/8" gap, so cutting plywood strips is my only option (there is NO composite furring strips available in town...I called everywhere!)

I've got the option of 3/8 spruce with exterior glue, or 3/8 fur with exterior glue.

Does either have a lower tannin content that may deteriorate the WRB? Do I even have to worry about that? Should I back prime the strapping to avoid this?

I'm going to put cement board over the strapping then stone.

Thanks!

In General questions | Asked By Mark Helmrich | Mar 16 15
26 Answers

Structural Insulated Panel (SIP) roof decay

I have a BensonWood timber frame in Vt that is only 8 years old with significant panel roof decay. So much so that my standing-seam metal roof has begun to rust from the inside out. There is evidence of SIP seam failure in several places below the standing-seam metal roof. Is it likely this was the cause? It is a hot roof.

In General questions | Asked By gregory raith | Oct 3 11
8 Answers

Alpen vs Inline

Hello,

I am comparing Alpen and Inline products. I have recieved quotations from both companies and I would like to pose a few questions to those that have a little more experience in this relam.

Both companies use fiberglass frames and Cardinal Low E Glass. Inline makes their frame and Alpen purchases the frame material through Inline.

Alpen makes a double pane window, their 525-s Series, that have a whole window U-factor of .19 for casements and .15 for pictures. Inline offers a triple pane window with a whole window u-factor of .17 for a casement and .14 for a picture.

In Green products and materials | Asked By David Mosijchuk | Mar 25 15
6 Answers

Suggestions/advice on vapor barrier product to use?

In the basement of my house (built in 1900) in NE Ohio...Half of the basement floor is finished, the other half is dirt floor covered by a few inches of crushed stone gravel. I had a mold issue, so looking to put a vapor barrier over the gravel floor. Also am getting slightly elevated radon level about about 4.9 to 5.1. I'm hoping maybe to solve both issue with one fix. Here's my dilema...I'm looking for a vapor barrier material that would withstand occassionally walking across it.

In General questions | Asked By Justin Stine | Mar 25 15
1 Answer

Improving panned return ducts

Our bungalow is a standard setup, with a 2 story addition added later. In the whole house, best I can tell, there are 3 return ducts, all on outside walls of the original house (1 is now interior), all on the 1st floor and all panned. I can access some of them from the basement.

The 2 farthest from the furnace are panned across to the center of the house, then in a duct going below the joists, then back into a panned duct that goes above the duct pushing air out, and then into another duct that goes back to the furnace, if that makes sense.

In Energy efficiency and durability | Asked By Jeremy M | Mar 25 15
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