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11 Answers

Hello, I am considering a whole-house dehumidifier and was wondering if there are any health concerns regarding pressurizing a home.

I am on the tail end of a large renovation project. The house has spray foam top bottom and sides. If I don't need an hrv/erv all the better, I am mainly interested in adequate fresh air and lowering the RH. I am in Massachusetts. Thanks for any help/comments

In Green building techniques | Asked By Gary Wilson | Aug 12 12
13 Answers

Flat Roof insulation Question No. 2

I have a client who has had problems with blown in insulation so that's not an option for our flat roof. Might we substitute rigid foam board on the underside of the roof sheathing (cut to fit in our framing bays) and then fill the rest of the cavity with blown in dry cellulose (or wet). We will be using a EPDM roofing membrane atop the sheathing. And if that's a possibility what type of rigid board (foil faced or not)?

Thank You!

In Green building techniques | Asked By Daniel Weaver | Aug 13 12
3 Answers

Socked draintile problem ?

This question from a builder in Zone 4
I found out something interesting last week. A lot of the manufactures won't warranty the socked draintile application in our area because of the soil conditions. Can we get an exclusion from this for ESTAR 3 because of this?
Doesn't make sense to me that if it is properly buried beneath 4" of aggregate and below the top of the footing that the soil condition should matter?

In Energy efficiency and durability | Asked By Rick Jenkins | Aug 13 12
12 Answers

Supplemental heat when we are away

We are about to start construction on our new home in Zone 6B upstate NY and are going to be putting in a 3 to 1 Mitusbishi mini split with two units ducted downstairs (living and master bedroom areas) and one wall or ducted unit upstairs. The house is 2,700 sf. with heating of ~13,000 BTU needed. The system should still provide enough heat at 17 degrees (16,000 BTU) and we plan to our wood stove for backup heat if it drops below 17 degrees or if the power goes out.

In Mechanicals | Asked By Elizabeth Kormos | Aug 9 12
4 Answers

Bug-proof foam coat?

My energy retrofit is in progress, and because of the peculiar way
the sill meets the foundation on the gable walls of the house, there's
an inch-plus gap between the block wall and the metal flashing the
builders attached to the sheathing to serve as the bottom base for the
rigid foam on the exterior. We're wondering how to fill this gap. I
looked at it and thought that a quick fillet of closed-cell sprayfoam
would be perfect, assuming it would stick permanently to both
the vertical concrete and up to the aluminum extending horizontally

In Green building techniques | Asked By Hobbit _ | Aug 10 12
3 Answers

Flat Roof Insulation Help


In Energy efficiency and durability | Asked By Daniel Weaver | Aug 10 12
3 Answers

Posting a link

Help with posting links. Right now I copy and paste...

In General questions | Asked By aj builder, Upstate NY Zone 6a | Aug 13 12
6 Answers

A wall with EIFS and SIS — What's the vapor profile?

I need a little help with a wall detail, for a three story house we're building in Arlington VA, Zone 4a mixed humid.

The lower 2/3 of the wall will be clad with EIFS. The upper 1/3 will be clad with a cementitious shake panel. The two finishes are separated by a water-table/apron like trim detail. 1" XPS will be continuous over the SIS on 2x6 framing with blown cellulose inclosed with ADA drywall. Cementous shake installed with rain screen, firring strips over XPS, flashed over the water-table trim.

In GBA Pro help | Asked By Mac Snelgrove | Aug 13 12
4 Answers

Ridge Vent Filter Question

I have a ridge vent that also has a "weather filter" I contacted the manufacturer and asked them what the felt filter does and they indicated that it keeps the "garbage out." My filter appears to be blocked by dust and it is ripped in several places. I am wondering if I should just rip it out since it looks to be blocked anyways. What would you all recommend, and is this filter very important? I am in zone 6. Thanks!

In General questions | Asked By Rocky Pembroke | Aug 13 12
4 Answers

New foundation installed under old house

We bought a house two years ago that sits on a shallow stone foundation with vented crawlspace, which until recently was only 0-12 inches deep. It has all the problems you'd expect from this setup--cold floors, musty smell, easy access for critters, rotted sills, etc. We had it vacuum excavated a couple of feet in order to gain access for installing vapor barrier on the ground and insulation between floor joist.

In Energy efficiency and durability | Asked By Steven O'Neil | Aug 13 12
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