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6 Answers

HVAC ducting - Climate Zone 7a

The house is 40 year old bungalow with heated basement. It has an older 80% efficiency forced air natural gas furnace with an input BTU/hr 88,000 and output BTU/hr 71,000 with 1400 CFM.

The living room is 268 sqft and is ~24% of the total volume of the main floor, which is open plan so it is connected to the dining room (268 srft) and kitchen (137 sqft), each being ~12% of tot vol, respectively. The living room is at grade level with 9.3' high ceilings, compared to the rest of the main floor that has 8' height ceilings and is ~2' above grade.

Asked By user-6759891 | Mar 19 17
0 Answers

SIGA Majcoat vs VaproShield SlopeShield

I'm designing my LAST house-- my retirement home, after having built several homes over my lifetime. My last was in Vermont in 2000, using ICF, in-floor radiant heat (walkout basement with concrete slab, upper floor with 1.5-inch poured gypcrete), standing seam roofing, closed-cell spray foam under roof deck.

Asked By Peter Martin | Mar 23 17
7 Answers

Buidling a house in Greenville, SC — insulation and air sealing questions

Building a house later this year. Plan to live in the home 30+ years. So I'm interested in the "long term."

The House: 3,350sf above grade. Very very little shade on this house. Kinda like building in the middle of a field. Lots of sunshine bearing down. Galvalume metal roof with 3/4" strapping between metal and synthetic felt (TBD). Zip System for exterior walls. 2x6 exterior walls. I'm planning on ponying up for the super efficient Trane XV20i heat pump. Cement fiber siding painted white.

The Plan:
Foam attic with open cell to 5.5-6".

Asked By jander5984 | Mar 15 17
11 Answers

Sound attenuation between floors

I am constructing a floor assembly between a 1st and 2nd floor and may not be able to build up a deep floor assembly due to exposed ceiling timber joists (and the small footprint of my structure). I am considering using 2 courses of Advantec (subfloor) material with perhaps a mass loaded vinyl material in between the subfloor material.

I was wondering if anyone else has constructed a floor assembly that might reduce some of the sound transfer without resorting to a deep floor framed system. Has anyone had success solving this problem?

Asked By John Brown | Mar 15 17
0 Answers

erv and flex duct

We're planning to install a Renewaire EV90P ERV with dedicated ductwork in our new 1900 sq ft home. It's going to be a budgetary strain to install hard pipe for all the entire system. So I'm hoping we can get away with a rigid duct for a trunk (running parallel to floor trusses) and then 6 inch flex duct going out to the exhaust and supply registers (through the webs of the floor trusses) - this is what the HVAC contractor is recommending, but I'm concerned about this small unit being able to handle the additional resistance to air flow from the flex duct.

Asked By William Costello | Mar 22 17
6 Answers

Eco Star windows and patio door

A friend had a sales visit from a contractor that installs Eco Star windows. Some of the R/U values my friend said he was promised sounded questionable to me. On the web I see they are reviewed well but would love a "real" experience from anyone in GBA. Anyone work with these?
Thanks, PK

Asked By Paul Kuenn | Mar 20 17
10 Answers

Do magic boxes distribute loads for ductless units?

For my pretty good home I am building( 2150 sq.ft. Zone 5 northern ct. near Sturbridge mass) I have recently got a quote back for mini splits. 5 heads 2 outdoor units Mitzi. Hyper heat. The contractor is at 17k installed. Diamond dealer. He has one head in each bedroom and 2 on the open floor plan. I am curious if there is a way to quantify how much a ducted ventilation system mixes the air around the home? Would a Minotair or cerv balance out the heating and cooling requiring more like 2 or 3 heads?

Asked By Scott Mangold | Mar 20 17
0 Answers

Air handler or fan coil for low load home?

Hello,

I am building a 2,000 sq.ft. townhouse in Oakland, CA. I plan to use a Sanden heat pump hot water heater to provide both domestic hot water and space heating. I am seeking guidance on how best to distribute the heat to the basement, first floor, second floor, and attic loft. Due to budgetary constraints, I am looking for the most economical heating distribution system. While a hydronic distribution system would be nice, I assume forced air is going to be my best bet - let me know if you disagree!

Asked By Gregory Sherman | Mar 22 17
0 Answers

How does ambient temperature affect wetting/drying cycles?

Hello GBA pros & community! I've been a lurker around here for awhile, but this is my first post. I'm enclosing a timber-frame in southeastern Manitoba (climate zone 7A), and plan to build a vented roof assembly with dense-packed cellulose insulation. For reference, the specific assembly I have in mind is as follows, from the inside:

-timber rafters
-1x6 T&G pine ceiling
-ice & water shield (interior air-barrier, class I vapour retarder, and temporary rain protection for the timber-frame)
-18" deep non-structural 'trusses' dense-packed with cellulose

Asked By Benjamin Pries | Mar 22 17
0 Answers

Exterior foam and Roxul batt on a reno

Have a client who has an older house he just purchased . Scarsdale NY . He intends to put 1" rigid foam outboard of the sheathing with Tyvek behind and 1x strapping to attach siding .

Interior first floor walls are 2 x 6 , second and third floor are 2 x 4 . Question 1 is what R value Roxul should he use in the 2 different wall assemblies ?

Second question is , is Tyvek the right product to use as the only barrier between the sheathing and exterior ?

Asked By Richard McGrath | Mar 22 17
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