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9 Answers

Sealing between floors on 1.5 story home?

High, I am currently building a 1.5 story home with 2.6 walls that will be insulated with blown cellulose. I am sealing all joints and penetrations with caulk and spray foam, and will doing R-38 in the vented attic.

I am concerned about the open space between joists between the upper and lower floors. I want to know if I should seal off this space so that the hot attic air does not infiltrate between the floors.

In Green building techniques | Asked By Dustin Gohmert | Apr 23 13
1 Answer

Spray foam and HRV system questions

Hi I have a raised ranch.
I am gutting the first floor and adding a 2nd story addition. With full attic.
I am going to use open cell spray foam.
All walls and attic roof lines. After the addition I will use it to finish the basement.
I am running a 90+ efficient furnace for the 1st floor and basement.
Which does draw fresh air into it
I am planning to get a similar unit for the addition
3 baths with fans, 1 600 CFM range hood
Would I need to install a HVR unit?
I live in the Midwest. I heard stories about windows icing up and having to open windows.

In Mechanicals | Asked By Brian Pasold | Apr 23 13
3 Answers

Split heat-pump water heater?

What's up with that ?
Are we again left in the dark zone or what ?

I've easily found a few hundreds of chinese units of split ait to water HP heater,
a euro Fujitsu model, some asian Toshiba models and a few DE and CH brands doing different designs ...

Am i missing something here ?
As far as i know, none of those are available in USA/CA
and they SHOULD BE.

anyone found a supplier in North America ??

i'd settle for anything better than our regular tanks ..

In General questions | Asked By Jin Kazama | Apr 23 13
18 Answers

Closed-cell spray foam insulation - is it safe?

We are reading lots of things about spray foam insulation, and have just had the attic space in our new home spray foamed with a closed cell variety. We are contemplating fiberglass batting in the rest of the house after reading that the offgasses from this spray foam installation can cause respiratory irritation, even after the initial 72 hours, particularly for those already suffering with asthma. The American Lung Asssociation recommends spray foam insulation. The EPA cautions about the respiratory irritation. What to do? Is this a safe product for home application?

In Green products and materials | Asked By Caroline Ferguson | Apr 21 13
14 Answers

Heat pump efficiency

I am designing 2700 sf 2 story house outside Sacramento, zone 3B. BeOpt suggests I will have about a 17,000 Btu heat need. AC is also a big need in summer, and since there is no natural gas, I figured on all electric. Propane appears to be quite a bit more money.

In General questions | Asked By Michael McKinley | Apr 8 13
8 Answers

Blower door on a new addition: suggestions?

I would like to perform blower door testing while performing air sealing on a new addition to an existing home. This addition is not connected at one point by a single doorway, of course, it is more of an open plan configuration. The existing part of the structure is old and leaky (air wise). Air sealing and energy improvements will have to come later to this part of the house (not my own).

In Energy efficiency and durability | Asked By Dennis Dipswitch | Apr 21 13
1 Answer

How do you frame a square pitched roof?

I am roofing a 10' by 10' shed and would like a four sided roof rather than having two gable ends.

In General questions | Asked By Mark Rogerson | Apr 23 13
2 Answers

Attic insulation depth above wall is less than wall insulation

I live in Madison, WI (cold climate). I have an old ranch home with 2x6 rafters with a deep soffit overhang (2ft). The rafters are notched at the top plates and I have about 2 inches of free space between the top plate and the plywood roof sheathing (assuming I keep an inch free for ventilation). The walls are 2x4 with plywood and Homasote sheathing.

In Energy efficiency and durability | Asked By John Haushalter | Apr 22 13
2 Answers

Duct or not to duct?

I know conventional wisdom dictates that ductwork should come off the trunk line and radiate out towards the exterior walls so registers can be placed above windows. I should say that I'm talking about New Orleans where homes are raised about 18" off the ground on piers, so we run the ductwork through the attic. If it's a two story house there is no room for chases between the floors.

In General questions | Asked By roger steinbrink | Apr 23 13
6 Answers

HVAC duct design

I just finished designing a 3700 sf / 2 story high-performing house in Dallas, TX. My Manual J calcs tell me I have 28 Kbtuh heat loss and 20 Kbtuh heat gain.

In General questions | Asked By Armando Cobo | Apr 22 13
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