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8 Answers

Bath exhaust fan pulling air from basement?

Hey guys,

We have been in our "Pretty Good House" for about 9 months now and still dialing in all the systems. Our blower door test was a .08 ach50, and we still have some holes to fill in the basement where the hvac line sets were cut through the walls. We have panasonic whispergreen bath fans that I have been fiddling with to get the right amount of continuous fresh air.

In Green building techniques | Asked By Clay Whitenack | Jul 6 18
6 Answers

N.Y. Times article on dealing with heat wave

I read this article

And while most of it is silliness it did get me wondering if white or reflective window coverings would make an appreciable difference. Assuming high SHGC windows of course (not sure if my windows are or not).

Your thoughts?

In Energy efficiency and durability | Asked By Alan B | Jul 16 18
5 Answers

Insulate addition walls, attic space, and partial cathedral ceiling


In Energy efficiency and durability | Asked By User-6903602 | Jul 16 18
21 Answers

Comfortboard pricing - Triple $ per R vs foamboard??

Hi all,

In Green products and materials | Asked By Keith H | Apr 21 16
20 Answers

Insulating an attic furnace room

I have a furnace in my attic around which the builder constructed an enclosure from 2X4 and foil-backed fiberglass insulation. I've been told the R-value of the insulation should be sufficient, but there is clearly air getting through at the seams and creating hot spots in the attic which then leads to ice dams etc. What is proper protocol for insulating these attic "furnace rooms"?

In General questions | Asked By Patrick Finn | Oct 15 14
16 Answers

Seal and insulate 1960s attic?

First off I apologize if this is the wrong category.

I currently have an L shaped ranch style home that was built in 1961 with a 3:12 slope hip roof with 3" overhangs. I currently have three gable vents, and no soffit venting. There is little to no insulation in the walls except on the south and west facing walls where I have opened them up over the years when doing renovations and installed R-13 fiberglass batt insulation. I would probably grade myself a II on install quality. In the attic there is blown in rockwool insulation about 6-8 inches deep.

In General questions | Asked By Striker169 | Feb 22 18
7 Answers

How to treat wet sandy cottage crawlspace in zone 5A/6A?

Situation: cottage on the sandy shores of a large lake in Michigan on the border of climate zones 5A and 6A. The cottage is set back from the lake front perhaps 200 feet, but is probably less than 2’ above lake level. The footings are likely below lake level. To make things worse, there is a natural drainage swale running behind the cottage that some good neighbors have effectively dammed, so there is permanent standing water about 100’ behind the cottage.

So of course the cottage is built with a crawlspace, with a sand floor and concrete block walls.

In Energy efficiency and durability | Asked By andrew c | Jul 14 18
12 Answers

Open truss post frame roof

I am building a cabin on Ky lake and want to do it post framed. The floor plan calls for vaulted ceiling over the kitchen and living area. I want to do exposed scissor trusses on 8’ centers. My thoughts were to span the trusses with vertical 2x6s on 24” centers and fill with batts then cover the bottom side between the trusses with tongue and groove pine. So what would I cover the top side 2x6s? I was thinking osb then 2” rigid foam then layer of 1/2 plywood screwed to the 2x6s then foil bubble wrap then metal.

In Green building techniques | Asked By kcov | Jul 8 18
6 Answers

Sealing a below-grade foundation wall penetration

What are the current acceptable approaches to sealing pipe penetrations through a below-grade foundation wall?

I've heard
1. high viscosity polyurethane
2. Low-expansion urethane foam + boot outside (fine homebuilding)
3. Other various boots

I will have a dimple membrane on the exterior.


In General questions | Asked By rossn1 | Jul 13 18
4 Answers

Anchor bolt o.c. spacing— earthquake retrofitting

I am trying to order some Simpson retrofit foundation plates and can’t figure out what o.c. Stands for in the table that tells you anchor bolt size, diameter of screw

Here is the context:

Anchor bolt o.c. spacing

Also in the chart that tells you allowable loads DF/SP (160) there are two columns F1 and F2. Not sure what that stands for

Thank you so much!

In GBA Pro help | Asked By user-7039450 | Jul 15 18
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