Insulation on the house was completed last week by the fabulous crew of Atlas Insulation. Ensuring that your home is properly insulated is a major factor to building a green home. Un-insulated or improperly insulated homes leak a home’s conditioned air outside, causing the homeowner to essentially pay to heat or cool the great outdoors.
There are a lot of factors and products that go into deciding the insulation of your home. You first must decide which insulation is right for your project and your budget, and makes sure that the R values meet building code requirements. The R value is a measure of thermal resistance used in the building and construction industry – the bigger the number the better the building insulation’s effectiveness. (see below for the Green Life Smart Life’s R values) There are several different insulations you can choose from, the most popular being blanket insulation and spray foam. We chose spray foam because of where we are located. Due to our high wind zone location we wanted to make sure the house felt as solid it was built. We didn’t want wind seeping through cracks and making the house feel drafty and we didn’t want that echo that you can get in open spaces.
We installed a mix of open and closed cell spray foam for the walls and ceilings of the home. In certain areas of the home, mainly where there are open soffits between the interior and exterior, spray foam isn’t applicable because it has nothing to bond to. For those few areas, we used a rolled insulation made entirely of recycled jeans that acted as the stop for the spray foam.
When installing the insulation, LEED-H requires that the home’s insulation meets or exceeds several grade specifications (listed below) of the ENERGY STAR requirements before it is even eligible to gain LEED points.
- Grade I – Meet the requirements of Grade II (below), but allow only very small gaps, and compression or incomplete fill amounts to 2% or less
- Grade II – Moderate to frequent installation defects, gaps around wiring, electric outlets, etc. and incomplete fill amounts to 10% or less. Gaps running clear through the insulation amount to no more than 2% of the total surface area covered by the insulation. Wall insulation is enclosed on all six sides and in substantial contact with the sheathing material on at least one side (interior or exterior) of the cavity.
Once each grade requirement is met, to earn an additional 2 points, LEED requires that the home’s insulation:
- Exceeds the R value requirements listed in Chapter 4 of the 2004 International Energy Conservation Code by at least 5%. Alternative wall and insulation systems, such as structural insulated panels and insulated concrete forms, must demonstrate a comparable R-value, but thermal mass or infiltration effects cannot be included in the R value calculation
- Install insulation to meet the Grade I specifications set by the National Home Energy Rating Standards (above). Insulation must be verified by an energy rater or Green Rater conducting a predrywall thermal bypass inspection.
We also added the extra effort of making sure we eliminated as many thermal breaks as possible. So if you look up at our roof we cover all of the rafters so you can’t see any wood break, this provides the roof a solid thermal barrier for maximum R values. We achieved R-51 in our roof; R-30 is the standard. The rest of our R values are listed below. The energy rater requires that they see the insulation at 80% and then again at 100% before the drywall is applied. We had our verification last week and we did extremely well. The verifier said that our insulation installation was “impressive”. Score one for us!
Be sure to check out our Spray Foam Gallery for some great shots of the insulation being installed.
Here are the R values for the house:
- Flat Ceiling: 12″ R51 Half Pound Density Spray Foam Insulation
- Garage Ceiling: 8 1/2″ R36 Half Pound Density Spray Foam Insulation
- Exterior Walls: 5 1/2″ R23 Half Pound Density Spray Foam Insulation
- Stairwell: 6″ R25 Half Pound High Density Spray Foam
- Stairwell: 3 1/2″ R15 Half Pound High Density Spray Foam
- Wall Upstairs between house and Roof of Garage: 3 1/2″ R15 Half Pound Density Open Cell Spray Foam Insulation
- Garage/House Wall: 5 1/2″ R23 Half Pound Density Spray Foam Insulation
- Garage Walls: 5 1/2″ R23 Half Pound Density Spray Foam Insulation
- Blockers: 5 1/2″ R23 Half Pound Density Spray Foam Insulation
- Overhang: 12″ R51 Half Pound Density Spray Foam Insulation
- Basement Closet Walls: 3 1/2″ R15 Half Pound Density Spray Foam Insulation
- Wine Room Walls: 3 1/2″ R15 Half Pound Density Spray Foam Insulation
- Basement Foyer Ceiling: 4 1/2″ R19 Half Pound Density Spray Foam Insulation
- Basement Closet Ceiling: 4 1/2″ R19 Half Pound Density Spray Foam Insulation
- Media Room Ceiling: 3 1/2″ R15 Half Pound Density Open Cell Spray Foam Insulation (for sound barrier)
- Laundry Wall: 3 1/2″ R15 Half Pound Density Open Cell Spray Foam Insulation (for sound barrier)
- Fill Blockers In Wine Room: 3 1/2″ R15 Half Pound Density Open Cell Spray Foam Insulation
- Wine Room Ceiling: 4 1/2″ R19 Half Pound Density Spray Foam Insulation
- Basement Ceiling: 4 1/2″ R19 Half Pound Density Spray Foam Insulation
- Fire stopping: Fill All Vertical Mechanical Penetrations in All Floors
- 21’x2’x14″ Area inside the house in the back of the overhang 1/2lb spray foam R59
- Seal around all doors and windows with low expanding cell foam.