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2 Answers

Moisture on my pole barn concrete floor

Inside my pole barn the concrete floor always feels damp. When we poured the floor years ago poured it over gravel. Someone said to me that I should have put a vapor barrier down like a sheet of plastic then poured over top of that. Well it's too late and I am in the process of making a little office inside my building and I don't want to have moisture issues in that room. What are some of my options? Thank you Anthony

In General questions | Asked By Anthony Grelli | Nov 18 15
1 Answer

New HVAC 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 GBA Pro help | Asked By Deidre Epperson | Nov 17 15
15 Answers

Sleeping coves betters than medium sized bedrooms?

I redesign old homes and rent them out. I found hallways are your worse enemies in use of space. It was not until this last year that I noticed hallways in my rentals that I didn't mean to make.

Lets take a bed of roughly five foot by seven foot for example. If I put this bed in the middle of the room with the headboard on a wall and put three feet around the bed I get a 11 foot by 10 foot bedroom. A typical bedroom size plus or minus. In this typical bedroom I have a roughly five foot by two foot closet.

Current Rental / Bedroom / Square Footage

In Interior design | Asked By S E | Oct 13 14
10 Answers

Unintended vapor barrier using oil-based stain on wood?

I need to stain some new bookcases (floor-to-ceiling) located on exterior walls. I want to use oil-based stain but am concerned that may act as a vapor barrier. The literature and other posts discuss the need to avoid vinyl wall paper or oil based paint on the wall in my climate zone (2B). Does oil-based stain (probably with varnish top coat) on the book case fall into this same category? The wall-to-book case surface of the book case is unpainted.

In General questions | Asked By John Walls | Nov 16 15
3 Answers

Zoned HVAC and dampers — Opinions?

Townhome has a zoned (3-levels) HVAC system. This system contains four trunk lines off the supply plenum one of which contains a weighted (manually adjusted) damper that was originally routed back into the supply plenum. This weighted damper is designed to provide bleed off air when less than 3 zones are in use.

You would adjust the damper by so that is operated as follows:

3-zones in use (damper is basically closed)
2-zones in use (damper partially open)
1-zone in use (damps is slightly more open vs 2 zones in use).


In Mechanicals | Asked By Chris M | Nov 18 15
3 Answers

Downloading Details

Details will not open in Autocad LT 16
Any Advice?

In GBA Pro help | Asked By Carole Coelho | Nov 18 15
7 Answers

Need a stealthy ERV installation

Hi, I own a 1450 SQFT home that has been spray foamed throughout (walls, attic, etc.) and has decent triple pane windows, but minimal to no passive solar due to orientation and surroundings. Although the home is 75 years old, a blower-door test revealed its tighter than most new builds, so I need a ERV as soon as possible. I chose an ERV over an HRV due to the humid summers and long dry winters here in MN. The home has a 96% efficiency gas furnace and central AC. The furnace has a multispeed fan.

In Mechanicals | Asked By Ryan Griffin | Oct 23 15
2 Answers

How to use polyiso as interior insulation on a pole barn?

I have an unfinished pole barn with board and batten siding in Pennsylvania. I'd like to insulate the inside with polyiso panels, because that way I won't have to frame out the walls, and the polyiso will create a handy air barrier and thermal break. I can also find used 3" panels for ~$20 around here. My plan is to glue 3 inches of polyiso directly to the inside of the Purlins, tape the seams, then screw OSB, plywood, or drywall on top with long screws. These screws will go all the way through the foam to the barn's 2x4 purlins.

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

Venmar C12 HRV vs. Venmar E15 HRV

Is anyone familiar with the differences between the Venmar C12 HRV / ERV series and the E15 ECM HRVs? The E15 ECM HRV is about $650 more expensive. I'm having it installed in conjunction with existing furnace ducting, but hope to not use the furnace fan to distribute the air.

So I'm mainly looking for advice on whether the features or efficiency of the E15 is worth the upcharge here.

Thanks for your help!

Ryan Griffin
1450SQFT low energy home
Minneapolis, MN

In Green products and materials | Asked By Ryan Griffin | Nov 18 15
5 Answers

Control a heat pump with a wall thermostat?

I have recently installed an airsource heat pump in my vacation house in central Vermont. It works great, and mostly replaces the electric baseboard heating.

My concern is that the unit can only be controlled by a hand held remote, and only goes down to 60 degrees. We normally leave the house at 45 when we are away. It seems to me I am wasting a lot of energy now, perhaps using even more than the baseboards at 45.

In Mechanicals | Asked By Philip | Nov 17 15
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