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3 Answers

Should I install insulation?

My house in LA is about 100 years old and there is no insulation within exterior stucco walls.

I'm debating whether I should install insulation (these pink sheets sold in home depot) since I have a chance to do so.

The stucco looks pretty thin to me. If rain water gets into these pink materials, would it cause fungus growth or maybe bugs build a nest within? A house has its own working built in ventilation and functioning mechanism for 100 years. Maybe I should not disturb it.

In General questions | Asked By liz lee | Jan 2 15
2 Answers

Rigid insulation and fiberglass batts in a wall cavity

I recently completed a full renovation of one bedroom in our home located in Central PA. When I had the room completely gutted i found that the house had been framed with rough cut (true) 2x4 studs. Because I had a full four inch cavity my father in law suggested that I install a layer of 1/2" blue board against the exterior sheathing for additional r-value and then install 3 1/2" fiberglass insulation. I followed his suggestion and closed the wall with 5/8" drywall.

In General questions | Asked By Austen Billman | Dec 31 14
2 Answers

Will 1/4" thick Pactiv fanfold foam work as a vent baffle in combination with mineral wool?

Sorry the previous question got cut off.
I'm not sure whether it's a condensation problem, as thin as it is.

In General questions | Asked By cameron morris | Jan 2 15
5 Answers

Lunos and range hoods

I am wondering if anyone might be able to help with a question that has come to my head. I am looking to use Lunos e2 fans for ventilation in my house, and I am also planning to install a 900 cfm range hood.

Here's what I have been wondering about: When the range hood is on, is that going to be causing strain on the Lunos motors, possibly to the point of damaging them? Let's say my house is about 1 ACH50, so fairly tight.

In Mechanicals | Asked By Stephen Youngquist | Jan 2 15
2 Answers

Insulating a 1 1/2 story brick veneer Cape Cod attic and kneewalls

I live in Portsmouth, VA(Climate Zone 4), in a Cape Cod style house with knee walls and slanted ceilings upstairs. I pay quite a bit to heat and cool my home. I crawled around the attic to get a good idea of what's there, and there isn't much. The floor joists between the first and second floor are not sealed. The area between these joists(in the lower attic) have a thin layer of blown in fiberglass, and no insulation in some places. Same goes for the slanted ceiling, and the top attic.

In Energy efficiency and durability | Asked By James ONeal | Jan 1 15
8 Answers

Zone 7 but limited to 1.5" of rigid foam. Worth it?

Been reading a ton of good info on here but still have some questions. I'm planning to strip my Zone 7 2x4 house to the 5/8" sheathing. I've already installed new windows made for 2x6 wall, so built out the frames 1.5" with 2x4's under the nailing fin.

I'd like to build the rest of the walls out 1.5", WRB, then hardie plank siding.

I was considering 2 options:
1- 1" XPS foam continuous, WRB, 1/2" furring strips, hardie plank

2- 1 1/2" XPS foam with furring strips set into furring strip channels, WRB, hardie plank

In Energy efficiency and durability | Asked By Dan Drackett | Jan 2 15
2 Answers

Minisplit or air-source heat pump in a remodeled 1920 bungalow?

Remodeling a 1920 Craftsman Bungalow. The home is in Zone 4A. The old Gas Furnace and AC System was working, however due to its age and a ducting system that is a disaster, it is being removed. The 2 second story bedrooms are being served by a non functioning Air Source Heat Pump located in the Attic with ducts run in the unconditioned space as well. The home is 3500 square feet with 2300 Sq Ft on the main level. The main level is open plan with a central hallway opening to the kitchen,living room, dining room. The master bedroom and bath are on the same level as well.

In Mechanicals | Asked By Sam Mashburn | Dec 31 14
14 Answers

Looking for "How to Install a Minisplit"

I have viewed most of the youtube videos, and looked for a publication, but I have failed to find a step by step, how to how to install a mini split heat pump. We had our Fujitsu installed about a month ago at our own home and I helped the HVAC do the install, I'm just not 100% on doing it myself yet.

I really think most builders with some speciality tools and some direction should be able to install a minisplits.

Any resources would be greatly appreciated...

In General questions | Asked By kye ford | Dec 22 14
8 Answers

Basement insulation (hybrid) - guidance needed

I am in the process of installing basement insulation in a new construction. I am looking at cost effective methods. I have 145' of below grade basement wall (9.5' tall). I have had the builder install a small amount at this point in one of the "immediately finished areas" approximately 30' x 9.5'.

Here is what I have so far (PLEASE COMMENT ON THIS)

ABOVE GRADE LIVING AREA 2x4 walls(scheduled insulation):
3.5" open cell in walls
R49 fiberglass blow in ceiling

ABOVE GRADE GARAGE 2X4 WALLS (scheduled insulation):
R13 fg batts in exterior walls
R19 fiberglass blow in ceiling

In Energy efficiency and durability | Asked By Jeremy McGill | Dec 28 14
2 Answers

Hybrid heat-pump hot water heater cooling effects

We have a GE hybrid heat pump hot water heater in the non-partitioned 1100 square foot basement of our pre-certified PassivHaus home in northern NJ.

We've found that when it's operating as a heat pump, it exhausts enough cold air that it actually cools the basement significantly.

In PassivHaus | Asked By Len Moskowitz | Dec 31 14
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