Where to Insulate During New Construction
Planning an energy smart home during the design phase is a strategy that will produce both a long term return on investment and help insure a comfortable home. When modeling a sculpture the clay remains pliable until it is put into the kiln. The same holds true for certain aspects on home building. Weatherization measures installed at the building stage will always be worth the investment. Knowing where to insulate during construction will help ensure a more energy efficient home.
Insulation
Lets start with insulation. It all starts at the top.

Attic Insulation - First we need decide what kind of insulation we want to use and then we will decide how much to build to. The types of attic insulation include:
  • Fiberglass - There are some applications where fiberglass insulation should be for like an unvented attic.

  • Cellulose - Blown in cellulose is the most commonly used product because of its performance and affordability. This is the insulation that is recommended by the Department of Energy . It has excellent air sealing characteristics and doesn't lose its R-value in extreme temperatures.

  • Open Cell Spray Foam - This product can be used when the insulation needs to be installed to the underside of the roof decking.

  • Closed Cell Spray Foam - This high performance product provides an airtight seal at the ceiling where it is need most. By creating an air barrier and having a very high R-Value you can maximise the performance of insulation in limited spaces. This product is very expensive and may not be used exclusively for attic insulation because the return on investment will take a long time.

  • Hybrid Insulation System - Our Hybrid Insulation system combines the high performance of foam with the affordability of cellulose.

Wall Insulation - is a big job, but the return on investment makes the work worthwhile. There are several choices for insulating products and applications for new construction projects. The types of wall insulation include:
  • Fiberglass batt insulation - can be an affordable way to insulate the walls. However, you want to be sure that you look at Blower Door Assisted Air Sealing before installing the insulation and make sure to carefully fit each batt into the wall cavities for thorough coverage. Install the paper side to the warm side and make careful cuts around electrical junction boxes and use tyvek tape on all the joints. The installation process is fairly easy, and the job will be done in no time. For 2x4 walls, you can achieve an R-value of 11. For 2x6 walls, you will achieve and R-19.

  • Wet-Spray Cellulose - is a better way to insulate your walls because of its air-sealing characteristics and higher R- Value per inch. Start with Blower Door assisted air sealing, and then you are ready to insulate. Properly installed, densely packed, wet-spray cellulose will achieve an R-Value of 15 for 2x4 walls and an R-Value of 22.5, an excellent value for the investment.

  • Open Cell Spray Foam - Expanding foam is the best way to make sure that every nook and cranny is insulated. With open cell 2-part foam, you get an excellent R-Value, and if you prep the walls with air sealing measures you will be happy with the performance. "

  • Closed Cell Spray Foam - Foam - Closed cell foam is the highest performing insulation on the market today. It produces an airtight seal and provides the maximum R-Value per inch.

  • Hybrid Insulation System - Our Hybrid insulation system is the most cost effective way insulate the walls in a new construction project. Installing 1” of closed cell spray foam and then filling the rest of the wall cavity with wet-spray cellulose will make the building airtight and provide the maximum R-value that the wall cavity will allow.

Floors - Floors are another hard-to-insulate area. The big question is: which kind of insulation is appropriate for certain applications?

Floors over an unconditioned crawl space, basement or a garage - These floors can be insulated with a closed-cell spray foam, open-cell spray foam or fiberglass batt insulation.
  • Fiberglass batt insulation may be used when you are on a budget. Installed carefully with the Kraft vapor barrier up (to the warm side) it can be effective.

  • Closed Cell Spray Foam would provide the maximum R-Value and an air barrier as well as a vapor barrier. Installed at a thickness of 4” (R-25).

  • Open Cell Spray Foam would also provide a good R-Value and may be the best choice when insulating a floor above a crawl space where a bathroom or kitchen is present. If for some reason water should spill onto the floor and find its way through to the insulation the open cells will allow it to drain. Installed at 6 ½ “ you will have a total of R-30.
Please note that floors that are insulated over a conditioned basement will not see an increase in energy efficiency. However, the residence will see some sound control benefits.


Band Sill - The Band sill is often overlooked and under insulated part of the home. Because it is at the lowest point in the pressure plan it is critical to make sure it has an air tight seal and proper level of insulation. There are two options.
  • Fiberglass - Fiberglass insulation can be used for this job as long as air sealing measures are included.

  • Closed Cell Spray Foam - Closed cell spray foam will provide an excellent air barrier, moisture barrier and the appropriate R-Value for this job. of 4” (R-25).

Crawl Space - "The crawl space is another tricky area when it comes to insulation decisions. The decision that needs to be made is whether or not it is for the best to include the crawl space in the thermal boundary. Many people do not want any part of having the crawl space included in the thermal boundary. However, this is usually the best case for an energy smart, comfortable home.

If you decide to include the crawlspace as a part of the thermal boundary:
  • Spray Foam - By insulating the foundation walls and band sill with closed cell spray foam and installing a vapor barrier on the ground you will see the best performance and keep out unwanted moisture or ground contaminants.
If the crawl space is going to be outside the thermal boundary you will want to insulate the floor above.


Blower Door Guided Air Sealing - The best time to get things sealed up properly and permanently is during the construction process. Prior to installing wall insulation, you can make sure unwanted air leaks are properly addressed. We also need to do some calculations to make sure the home has the proper amount of ventilation needed. There may be a need for a mechanical fresh air exchanger that will introduce fresh air into the home without losing valuable conditioned air..