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1 Answer

New house CZ3, ducted HVAC & air handling design questions

2500sf single story 3 bedroom north bay, California house with conditioned rat slab crawlspace. 3 bathrooms, family rooms with a gas fireplace, "great room" kitchen/DR/LR is 30x42.

Plans call for 2x6 walls with 1" of well sealed foam (exact type still tbd), 500sf of casement windows and french doors with sub-.30 ufactor glazing, unvented 6/12 exterior pitch scissor trusses.

In Energy efficiency and durability | Asked By Rob Hunter | Jan 21 18
5 Answers

Wood stove backdraft

Hi all,

In General questions | Asked By Randy Williams | Jan 19 18
3 Answers

Foundation Uplift

I am planning to build a 2 story standard colonial (28 x 36) in lower Michigan using Sips upper walls and a PWF conditioned crawlspace foundation. I am somewhat puzzled by how uplift is prevented in some of the PWF recommendations I see proposed. I will not be back filling the interior walls so it appears there are 2 options. Pour a 3-1/2" concrete floor( attach to wall via a screed board with embedded fasteners) or build a treated regular joist floor?

In General questions | Asked By William Oldaker | Jan 21 18
17 Answers

Cycling of heat pump

I have a Fujitsu heat pump with two indoor units each in relatively small rooms. (For good or bad, this decision was made because I was not satisfied if only one room had a unit that sufficient heat could be transmitted to the second room and I wanted each room to have its own thermostat. I recognize that they are larger than I need but I did not see good alternatives) Currently both units are set on "minimum heat" (50 degrees F) because the rooms are not occupied for days at a time.

In Energy efficiency and durability | Asked By David Martin | Jan 14 18
11 Answers

What materials meet code for "flash and batt" on my ceiling?

I have an unfinished basement and I am looking to add about 5" of insulation to fill up the joist bays on the ceiling. The bays are 7 inches deep and will soon have around 2" of foam.

I am wondering if I would be able to fill the bays with Roxul and cover the entire ceiling with house wrap.

The reason for the roxul is that if necessary it would still be possible to access what's in my ceiling (wiring and some pipes), without the negative effects on air quality of the fiberglass.

I understand I can trim the roxul with a knife to match my very uneven 80 year old ceiling joist bays.

In Energy efficiency and durability | Asked By Robert Wan | Jan 12 18
18 Answers

Duct board repair/starter collar holder help

A contractor who installed my heater wrong/ I had to replace it after 12 years.
is now fixing my duct system to make me happy, (per them)
the duct system is duct board 26.5" wide 15.5" tall that runs like an L
around say 13 feet then L then say 75 feet long.
it dips down in the middle then goes back up but its all the same size.
from that flex taps off the box to the vents along the way and at the end they ran a 10" scoop to 8x8x8 and then 8x6x8 so its two 8 inch and one 6 inch flex at the vary end of the duct board.

In Building Code Questions | Asked By Chicken123 | Jan 21 18
11 Answers

What should I replace my heating and cooling system with?

Hi all,

I'm looking for advice on the 'best' solution to my heating and cooling (and hot water)

- Zone 5b
- Loads from coolcalc and manual D/J
Heating loads
- Main house: 28k to 36k, 900 cfm
- Sunroom addition (can be closed off): 8k, 150 cfm unducted not planning to directly heat (current situation)
- Office addition 5k/3k, 180 cfm. Unducted, can probably be heated via staircase.

Cooling:
- Main house cooling load: 24k to 36k, 1200 cfm
- Sunroom addition: 8k, 450 cfm unducted not planning to directly heat (current situation)

In Mechanicals | Asked By Jill D | Jan 17 18
13 Answers

Heat loss, can lights in cathedral ceiling

The information about replacing or retrofitting can lights with LED fixtures has been really helpful. However, I have a cathedral ceiling with what I think are standard can lights, with a diameter of 7.5" within the can, and about 9.5 " total diameter including trim--the ceilings are about 18' high so I am having a difficult time getting to one to carefully measure.

I cannot find anywhere residential can light LED retrofits for this size. I've looked at what Cree offers, as well as Home Depot and Lowes, and they all max out at 6".

In Energy efficiency and durability | Asked By JWBDSR | Oct 17 17
0 Answers

Basement floor underlayment

I am considering putting down a 12mm laminate floor in my Michigan basement, with the primary goal of "warming up" the floor surface. Currently there are vinyl tiles on the floor with many of them missing. The house was built in the 1950s and has a low (7'1") floor to ceiling joist bottom height. What I am considering is using Selitac underlayment by Shaw Floors, which is a relatively thin (2mm) foil-faced, insulated material that would not contribute to headroom problems. I would tape all of the abutting seams of each piece as recommended.

In General questions | Asked By Jay Jackson | Jan 21 18
3 Answers

Options for reducing ladybug infestation?

Is there a good "green" way to get rid of ladybugs?

We have hundreds in the walls in our house. Unfortunately it is not possible to completely seal this old house, so we have them crawling into the attic, into the bathroom, and now they are crawling all over the closed cell foam. I wonder if they eat sawdust, or maybe the operation of power tools in the attic creates vibrations that make them come out of their crevices.

In Green building techniques | Asked By rich cowen | Jan 21 18
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