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6 Answers

Heat pump water heater in an unconditioned attic... any issues?

I'm working with a builder building some townhomes in Orlando. One option is for them to install heat pump water heaters in the unconditioned attic (R38 blown cellulose floor). There are a couple concerns I have:

1. Will it be too cold in the winter? The 97.5% heating design temp in Orlando is 38F. I expect this, plus the small temp buffer from being in an attic, should make freezing not a problem. Does anyone have experience with this?

In Green products and materials | Asked By Cy Kilbourn | Nov 19 15
5 Answers

Is thermal imaging accurate?

Customer had a thermal imaging co come out .images showed temperature deference so around wall outlets and switches.He thinks it is because of bad insulation install around them . ????Isn't there a building code not to pack or install too tightly ???

In General questions | Asked By Will | Nov 18 15
3 Answers

Tape AND caulk around windows?

I'm planning how we'll install the windows in our house build and recently read Brian Knight's very good article in Fine Homebuilding. If you haven't seen it, Brian has it on his website:


and FHB has videos based on the article:


In General questions | Asked By Nick Hall | Nov 19 15
1 Answer

We have had a dog kennel for several dogs which we plan to remodel

We have had a dog kennel for several dogs which we plan to remodel. It has had painted OSB as exterior siding for several years.

We want to add new plywood siding on top of the OSB. Do you think we should take OSB off and replace it or add paper and a rain screen or 3/9" spacers so it can dry out? This is in n. CA. with lots of rain.

In Energy efficiency and durability | Asked By John | Nov 20 15
5 Answers

External air barrier and batt insulation

If batt insulation is used along with an internal air barrier (drywall system) do I still need an external air barrier? I mean, if there were no good air barrier on the outside, wouldn't cold air from the outside blow into the fiberglass or rockwool and kill its insulation properties, regardless of how tight the drywall barrier was?

In Green building techniques | Asked By Jack | Nov 20 15
8 Answers

Insulating an old cinder-block building

Hello! I have a 1975 building that I am renovating. It is primarily a cinder/masonry block building.

The blocks are standard 16" x 10". There is no insulation in the cavity (vermiculite) of the blocks.

In General questions | Asked By Russell | Nov 19 15
4 Answers

New HVAC problems — health problems

I recently had my hvac system and all flex duct replaced due to age of unit and mold throughout. I live in a Florida 1930's home and the ducts are in the crawl space under the house, also we have had a problem with critters making holes in the ducts.

In General questions | Asked By Deidre Epperson | Nov 18 15
3 Answers

Desuperheater water heater

I always understood that if you had a GSHP with a desuperheater, that your water heater should be an electric tank type. A client we are designing a home for would prefer a gas tank over electric, and our MEP engineer has not suggested that this would create any issues. Please advise.

In Mechanicals | Asked By Heather Gayle Holdridge | Nov 19 15
7 Answers

Obscured glass entry door and solar heat gain

This is a weird question, but who else would I ask, but all of you. I want to know if there is privacy glass that still offers decent solar heat gain, and if one type is better than another.

The front of my home faces South and also faces the street on a city block. I want a glass entry door for natural light and solar heat gain in the winter (yard is shaded in summer) Provia makes Quad pane doors 2.5" thick that seem like they might fit the bill with U values as low as 0.13 (the same as my windows, coincidentally): http://www.proviaproducts.com/productdetail/entry-doors/embarq-glass

In Green building techniques | Asked By Ryan | Nov 17 15
1 Answer

Best approach to insulate rooms in a timber frame barn.


In Energy efficiency and durability | Asked By Maciej Szefler | Nov 19 15
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