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0 Answers

Naive question on LEED certification


Asked By Brian Gray | Jul 21 17
3 Answers

portable dehumidifiers

Are there any that are as efficient as Santa Fe? And durable/reliable too? I need something that extracts about 40 pints a day.

Asked By charles CAMPBELL | Jul 21 17
2 Answers

Humidity and negative pressure

A customers home (zone 4 non-marine) has condensation problems (summertime) on a particular HVAC duct. Upon inspection the %RH was at 60%. There is a whole house dehumidifier hooked in with the HVAC System (Fan runs at low speed continuously) Bathroom exhaust fans are backflowing and letting in a significant amount of heat, and when opening the front door one can feel the hot air entering the house. There is no ductwork in the attic, it is all in the basement.

Asked By Jeff Classen | Jul 20 17
0 Answers

HVAC question


We are building an energy efficient 2700 sq foot ranch, open concept. We live in Wisconsin and leave the windows closed year round due to allergies. So, the AC or Heat is normally running.

It has been suggested that I get an HRV. It has also been suggested that I get a whole house air purifier. Do I need both? Or maybe just and HRV and 4' media filter?

For the HRV, I have seen Lifebreath or Zehnder? Either one better, or other brands to consider?

My builder is not familiar with these specific types of products.

Thanks in advance for any help!


Asked By jabehling | Jul 21 17
2 Answers

What Mil vapor barrier will stop radon too?

I am going to install new plastic over the gravel in my crawl space. My primary goal is to reduce humidity. I was reading about radon and I might as well put down a plastic that will block both.

How thick of plastic do I need to stop humidity and radon?

Asked By 99IdoDIY | Jul 21 17
9 Answers

Insulation question and new construction.... thoughts?

New construction, we are doing a non-vented attic to keep our HVAC ductwork in a conditioned space with foam on the roof deck. Come to find out, we can put foam in all the walls vs using bibs for the same price which surprised me. This will make for a tight house and this brings the question in my mind "what type of mechanical ventilation"? House needs to breath and have a good exchange of air.

House is a 2 story and about 2700 sq ft. 2 HVAC units will be installed. Biggest concern is a good ventilation system..

Asked By Thomas Roberts | Jul 20 17
3 Answers

Venting for multiple appliances

Hey GBA,

I wanted to reach out to the community for a thought experiment.

The home I am building will have the following :

High efficiency Gas furnace
High efficiency Gas water heater
Central vacuum

All of these require exterior intakes and exhausts.

The house is a row house, so the majority of the side walls are attached to another house. Thus, this only leaves one spot where I can place the multitude of vent pipes. (which is pretty much a small alcove at the rear between the two houses) see attached image.

Asked By Jamie B | Jul 21 17
6 Answers

Insulating floor before subfloor goes in.

I need to insulate the floor of Dear Old Mom's house in zone 4c to r-38 to earn enough green "credits." Conditioned crawl is not an option because of our hot radon potential. 22" crawl space makes working down there very difficult.
Would this work:
Cut 3" poly iso (R-19.6) to fit between the webs of the 9 ½" TJIs (19.2 o.c.) and rest them on the bottom flanges before the subfloor is installed (or stage the cut pieces in the crawl before the subfloor goes in). Later, cut access holes and blow cellulose to fill the remainder of joist bay.

Asked By Mark Walker | Jul 21 17
6 Answers

Insulating balloon walls

High I am renovating a 1927 Dutch colonial with balloon wall construction. Th attic is finished but will be taken down to exposed walls and rafters. The exterior will be resided on the second level with Hardy board fibercement clapboards. The ground level is one layer of brick over wood sheathing. The roof will be replaced with an imitation slate product (DaVinci roof scrapes). All the windows were already replaced (Trim line) Aluminum clad wood thermopane windows. My question is about insulation. I will be cutting a ridge vent.

Asked By eh413 | Jul 20 17
6 Answers

EPS under siding

Hi all, I have a weekend cottage on a lake here in middle GA that was built in the mid-80’s that is in need of some serious TLC. One of the projects I’m planning on doing is to re-side the house with Hardiplank lap siding. The current siding is cedar lap on top of 1” foil faced Expanded Polystyrene (EPS). The corners are set with ½” plywood and ½” GP particle board for shear strength. Currently, there is no felt or house wrap between the sheathing and cedar siding. Due to 10 years of lack of maintenance and woodpeckers; the current cedar siding is in really bad shape.

Asked By Rudi Schmoll | Jul 21 17
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