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10 Answers

Exterior Insulation on Cinder Block Walls

I have been through many articles talking about exterior insulation techniques, and insulating the exterior of foundations. My house is a little unique, and I'm hoping that someone can offer some insights/guidelines on how to handle things.

Asked By Jameson Taylor | May 18 18
7 Answers

Spray foam from crawlspace onto bottom of plank subfloor in Pacific NW?

Hi there - I'm in a 1955 house in Seattle, WA, over a vented, unconditioned crawlspace, with hardwood flooring on top of plank subfloor with no insulation under it.

Asked By Frasca | May 21 18
12 Answers

Water heater pad

My HPWH is going in a tall crawlspace and I want to protect the base. Since it is going in before the crawlspoace is conditioned, I was thinking about using a condenser pad, but most of those top out at less than 400 lbs or load and my water heated will weigh roughly twice that when filled.

I found the Insulfoam water heater pad, but it is not available online from what I can tell.

What alternatives are there?

Asked By Norman Bunn | May 17 18
4 Answers

Spray foam questions

Hello all, thanks for any help in advanced.

Asked By Stanger133 | May 20 18
3 Answers

Exterior sheathing and insulation

Hello new member here. Plan on building a home in TN, climate zone 4A. Want to make this home very efficient and comfortable. Planning on geothermal ground exchange HVAC as no natural gas is available in the area. My question is around exterior wall insulation.

Asked By Cdgatti | May 21 18
0 Answers

Difficulty Finding a Modulating Multi-Zone ASHP

I need to finalize the equipment selection for my current build. My engineer along with Mitsubishi spec'd a City Multi (VRF) PUMY outdoor unit with multiple indoor units. Unfortunately, this outdoor unit does not have hyper-heat, which means that in order to meet the 99% heating requirements, it will be grossly oversized for cooling. While the compressor can operate down to low-20% of rated capacity, that is still much higher than an MXZ minimum operation for the same sized unit.

Asked By Jonathan Lawrence CZ 4A New Jersey | May 21 18
10 Answers

Water Testing After Pex Repipe

I live in South Orange County, California, a repiping companies paradise. A massive amount of newer homes are being forced to repipe due to copper failing and slab leaks. The pinhole leaks begin developing between 8 to 15 years after the home is built and sometimes sooner. The theory according to most is that the builders went cheap and installed copper M in the homes, while the water company uses cholormine which the Copper M can’t handle. Most repiping companies will recommend PEX A, but also market USA made Copper L for the repipe.

Asked By JohnZ99 | May 16 18
10 Answers

Attic ventilation needed for a 100-year-old slate roof in a coldish climate?

Hi all,

First time owners looking at 100 year old house in NE US (climate zone 7).

Beautiful slate roof, very steep (making the attic much smaller than 1300 sq foot footprint of house).

Attic is totally not vented.

Inspector said to look into venting it to help roof last longer.

My question is, it’s lasted this long (I’m sure it’s had repairs along the way) is it safer to leave as is or look into venting?

Asked By slateandall | May 21 18
13 Answers

Water cooled refrigerator coils

This may seem weird, but I’m curious...

We just bought acreage in west central Florida and we’re planning our home. We plan on making everything as energy efficient as we possibly can, and I ve been researching geothermal ground loop heat pumps.

As I’m grabbing some leftovers out of the fridge, I feel hot air being blown on my feet from the condenser coils underneath. At the same time I hear the AC kick on outside. The lightbulb flickers on above my head... I’m running the AC to cool the room that is being warmed by the fridge...

Asked By LT.Son | May 19 18
4 Answers

Tyvek over foil-faced polyiso

I was looking a the spec sheets for foil faced polyisocyanurate and it gives an R value for the foam and then a R value of the foam with an air space. For example, the 3/4" foam has an R value of 5, but the R value of the foam with 3/4" reflective air space is 7.5. If I'm installing foam, covered in Tyvek then 3/4" furring strips with siding, do I have the reflective air space to get the R of 7.5 since the Tyvek is directly over the foil facing?

Asked By E247 | May 19 18
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