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3 Answers

HRV internal ductwork ....does it need insulation?

I understand that any ductwork connecting to the exterior of the building will need insulation (to prevent condensation). Do I need to insulate the internal ductwork that carries the air to and from my rooms? I was planning on just using 6" vinyl ducts. THANKS.

In Green products and materials | Asked By STEVEN JEWETT | Feb 7 14
5 Answers

How to quiet a tongue-and-groove floor?

Planning on using 2x6 T&G flooring in a timber-frame. Not too concerned about 1st floor, but there will be 2nd floor bedrooms over the 1st floor master bedroom and loft area over kitchen.

Any thoughts as to soften the sound transfer between floors?

In General questions | Asked By John H. Stehman | Feb 4 14
2 Answers

Roxul R-value misprint?

I bought 24 bags of 7.25" Roxul. The bag says R-30, but some of the Roxul had R-14 printed on one side.

It all measured the same thickness. Was this a misprint? Has anyone seen this before?

In General questions | Asked By darren williams | Feb 7 14
1 Answer

Concerning attic insulation

My furnace is in the attic. Also, I live in Oklahoma City.

Should I put insulation between the roof rafters? Does there need to be a moisture barrier against the roof sheathing? How should it be properly installed?

I purchased unfaced insulation. Can I still use this? And what will be the way to install?

I would very much like to hear from you and get the best way to use what I have at this point.
Thank you,
Nathan Adolph

In GBA Pro help | Asked By nathan adolph | Feb 7 14
7 Answers

Can I install 2"-3" of concrete in a 6" exterior wall?

The exterior walls on the house are 6" wood frame. I want to insulate the walls either with 2" or 3" of insulation and leave enough space for 2 1/2" to 3 1/2" of concrete. The concrete will only be poured to about 6' above the floor with the taller remaining space on the 9' walls to be 5 1/2" of blown insulation. Can I sandwich the cement between 1 1/2" sheets of extruded polystyrene? Will moisture weep on the inside surface of the cement in cold weather?


In General questions | Asked By Wayne McConnell | Feb 5 14
1 Answer

Combined gas and wood smoke vent?

Can I join a wood smoke vent pipe with an existing vent pipe from my gas central heating unit in the attic so I have only one vent through the roof?

I would like to install a wood burning stove and the vent pipe through the ceiling into the attic is on approximately the same line as the existing vent pipe from the central heat unit in the attic and already vented through the roof. It would be nice if I could just tie into the existing pipe in the attic so I don't need to cut a separate hole right next to the one already there.

In General questions | Asked By Lloyd Walker | Feb 7 14
2 Answers

Thermofoil - any info?

I keep running across Thermofoil cabinets that are touted as "green" because of their durability yet it's made of vinyl and glued onto (not necessarily NAUF nor FSC certified) MDF. Do you have any info/opinions?


In Green products and materials | Asked By Bettina Hoar | Feb 5 14
2 Answers

Flash-and-fill double-stud walls?

After reading the Building science article regarding moisture monitoring in high R value walls:


I became interested in the idea of a flash and fill double stud wall. (new construction climate zone 6 - northern New England) as a "safe" wall for my location.

In General questions | Asked By Christopher McKay | Feb 7 14
6 Answers

Exterior roof sheathing ventilation

I am designing a 2,000 sf [pretty good passivehouse] house in Colorado. The site is in Zone 7B, 10,000 HDD; -16 Design Temperature @ 8500' elevation, in other words, damn cold.

We are implementing most, best building practices where practical for this budget [current energy model at 21,000 BTU/hr]. We will have interior and exterior air barriers.

In Green building techniques | Asked By Tim Van Meter | Feb 3 14
5 Answers

Adding ceiling insulation...

My son's house has R-38 fiberglass batt (12") above the bedroom ceiling. There is vented attic space above that. While the R-38 may be a decent # in theory (though R-50 would probably be the current zone 6 amount), I'm thinking the air sealing capability here is slim to none (below batts is the kraft facing stapled to joist bottoms and 1/2" sheetrock.

In Energy efficiency and durability | Asked By Howard Gentler | Feb 5 14
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