| Feature Technologies |
| Following is an explanation of many of the building technologies we are using in our Demonstration Home. Some of these products are now common in the residential building industry while others are new. |
FLOOR SYSTEM: ILEVEL BY WEYERHAEUSER
Although developed 35 years ago, engineered floor systems have only
become a major factor in homebuilding the last few years as the price
has become more competitive with dimensional lumber. Our
Demonstration Home uses the FrameWorks Floor system which includes
TJI Joists (Trus Joists) with Timberstrand LSL Rim Board. The
dimensional stability of TJI Joists helps them resist warping, shrinking,
and twisting which can lead to squeaky or bouncy floors. The
engineered joists are then joined together with a rim board using the
laminated strand lumber, which is designed so that it is always straight,
true, and consistent. In fact the main stair stringers are made from
Timberstrand LSL as the quality is so much better than a standard 2x12.
The FrameWorks Floor system is also ideal from an environmental
perspective as the components are manufactured from wood strands
instead of sawn from whole trees. And since the system is designed for
each individual home, there is almost no waste, another element of the
LEED point system.
SUBFLOOR: ADVANTECH BY HUBER
AdvanTech is another product that has quickly become an industry
standard by combining the best features of plywood and oriented strand
board (osb) flooring panels. It is engineered for superior moisture
resistance, design bending strength, and design stiffness compared to
both plywood and osb. Each 4x8 sheet is consistent, smooth, and
backed by a 50-year limited warranty. Our own experience shows that it
does not have the moisture problems common with other subfloor
products.
AdvanTech is manufactured from wood strands like osb so it is
considered green. And Huber has a plant in Maine which cuts the
shipping (LEED for Homes awards material points for local items).
WALL AND ROOF SHEATHING: ZIP SYSTEM BY HUBER
We are thrilled that our demonstration home is one of the first in New
Hampshire to use the ZIP System Wall Sheathing! This new product is a
result of the very latest thinking in how to protect the building envelope
from moisture while still letting it breath. Each 4x8 wall panel is a 7/16”
osb type panel with a water-restive barrier included. The seams are
simply taped after installation and you have a complete water barrier
(also known as the drainage plain). The Zip panels eliminate the need
for house wrap which is often poorly applied on site and not properly
taped. Because the system is much tighter than traditional house wrap, it
also controls drafts. And the panels are engineered to allow the wall
system to breathe. No wonder the ZIP System Wall won Building
Products Magazine 2007 Award for Most Valuable Product. (link)
The Zip System Roof is a structural panel with a built-in moisture resistive
barrier that eliminates felt or tar paper and H-clips. Similarly it is taped
with the Zip System tape after it is installed and is water tight.
The Zip System panel use wood strands and recycled material and is
also produced by Huber within 500 miles so it qualifies for LEED material
points. Better yet, it is an engineered system that takes into account the
effect of moisture on the home.
21st CENTURY INSULATION
One of the major components of the Demonstration Green Home is the
insulation package. Energy Star is a prerequisite of the LEEDs for
Homes program but there are different levels of Energy Star performance
which used to be measured using a star rating (1-5 stars) but is now
measured by the HERS index.
One of the limitations of a conventional frame wall is the “thermal break”
everywhere there is framing lumber on the exterior walls. We minimized
the breaks by using high performance framing techniques and
eliminating as much unnecessary wood as possible. We also insulated
the headers over doors and windows which are usually the largest
thermal breaks.
Next we sprayed 1” of polyurethane closed-cell foam. The foam expands
to fill the bays between the studs and fills the plumbing and electrical
connections through the exterior walls. 1” is the amount required to
achieve a true air barrier in the wall. There is also a study showing that
1” of foam stops 70% of heat loss from conductance through the wall
insulation. We could have sprayed more foam but it is very expensive. A
good trade off would be to frame the walls with 2x4 instead of 2x6 studs
and fill that with 3 ½” of foam but many buyers perceive this as “cheap”
construction. In fact, the only reason 2x6 exterior walls are considered
standard is that the R19 fiberglass batts commonly used is the easiest
way to meet the energy code.
Next we used the Certainteed Blow-in-Blanket (BIBS) system which uses
small fiberglass pieces blown behind fiber netting. Properly applied, this
system achieves a seamless blanket with uniform density while filling in
gaps behind pipes and outlet boxes. This ensures a uniform R value
throughout the wall cavity and helps control air infiltration. The result is
slightly greater than an R4 per inch which when added to the R6 to 7 of
the foam results in a conventional 2x6 wall with an R value of 25 to 26,
and more importantly, no air infiltration. We feel this combination
achieves the best ratio of price to performance currently available.
An insulated space is needed for the geothermal heat pump and the
Energy Star raters also prefer that the foundation walls be insulated (as
opposed to the basement ceiling). We installed R5 rigid foam and then
R13 batts in a 2x4 frame wall around the foundation. The attic has an
R49 blown cellulose with an Energy Star compliant scuttle cover. The
expected HERS rating is somewhere around 60 which would be a 5 stars
+ rating.
The other options for a high performance house would be a double wall
system or a structural insulated panel (SIP). Either will add considerably
to the cost. Since we are limited by current exterior door and window
technology (that is where the air infiltration comes from in a tight house),
you would need to do a real cost benefit analysis to see if these options
would pay back your investment. Of course, if you decide they do, we will
be happy to build it with you!
Although developed 35 years ago, engineered floor systems have only
become a major factor in homebuilding the last few years as the price
has become more competitive with dimensional lumber. Our
Demonstration Home uses the FrameWorks Floor system which includes
TJI Joists (Trus Joists) with Timberstrand LSL Rim Board. The
dimensional stability of TJI Joists helps them resist warping, shrinking,
and twisting which can lead to squeaky or bouncy floors. The
engineered joists are then joined together with a rim board using the
laminated strand lumber, which is designed so that it is always straight,
true, and consistent. In fact the main stair stringers are made from
Timberstrand LSL as the quality is so much better than a standard 2x12.
The FrameWorks Floor system is also ideal from an environmental
perspective as the components are manufactured from wood strands
instead of sawn from whole trees. And since the system is designed for
each individual home, there is almost no waste, another element of the
LEED point system.
SUBFLOOR: ADVANTECH BY HUBER
AdvanTech is another product that has quickly become an industry
standard by combining the best features of plywood and oriented strand
board (osb) flooring panels. It is engineered for superior moisture
resistance, design bending strength, and design stiffness compared to
both plywood and osb. Each 4x8 sheet is consistent, smooth, and
backed by a 50-year limited warranty. Our own experience shows that it
does not have the moisture problems common with other subfloor
products.
AdvanTech is manufactured from wood strands like osb so it is
considered green. And Huber has a plant in Maine which cuts the
shipping (LEED for Homes awards material points for local items).
WALL AND ROOF SHEATHING: ZIP SYSTEM BY HUBER
We are thrilled that our demonstration home is one of the first in New
Hampshire to use the ZIP System Wall Sheathing! This new product is a
result of the very latest thinking in how to protect the building envelope
from moisture while still letting it breath. Each 4x8 wall panel is a 7/16”
osb type panel with a water-restive barrier included. The seams are
simply taped after installation and you have a complete water barrier
(also known as the drainage plain). The Zip panels eliminate the need
for house wrap which is often poorly applied on site and not properly
taped. Because the system is much tighter than traditional house wrap, it
also controls drafts. And the panels are engineered to allow the wall
system to breathe. No wonder the ZIP System Wall won Building
Products Magazine 2007 Award for Most Valuable Product. (link)
The Zip System Roof is a structural panel with a built-in moisture resistive
barrier that eliminates felt or tar paper and H-clips. Similarly it is taped
with the Zip System tape after it is installed and is water tight.
The Zip System panel use wood strands and recycled material and is
also produced by Huber within 500 miles so it qualifies for LEED material
points. Better yet, it is an engineered system that takes into account the
effect of moisture on the home.
21st CENTURY INSULATION
One of the major components of the Demonstration Green Home is the
insulation package. Energy Star is a prerequisite of the LEEDs for
Homes program but there are different levels of Energy Star performance
which used to be measured using a star rating (1-5 stars) but is now
measured by the HERS index.
One of the limitations of a conventional frame wall is the “thermal break”
everywhere there is framing lumber on the exterior walls. We minimized
the breaks by using high performance framing techniques and
eliminating as much unnecessary wood as possible. We also insulated
the headers over doors and windows which are usually the largest
thermal breaks.
Next we sprayed 1” of polyurethane closed-cell foam. The foam expands
to fill the bays between the studs and fills the plumbing and electrical
connections through the exterior walls. 1” is the amount required to
achieve a true air barrier in the wall. There is also a study showing that
1” of foam stops 70% of heat loss from conductance through the wall
insulation. We could have sprayed more foam but it is very expensive. A
good trade off would be to frame the walls with 2x4 instead of 2x6 studs
and fill that with 3 ½” of foam but many buyers perceive this as “cheap”
construction. In fact, the only reason 2x6 exterior walls are considered
standard is that the R19 fiberglass batts commonly used is the easiest
way to meet the energy code.
Next we used the Certainteed Blow-in-Blanket (BIBS) system which uses
small fiberglass pieces blown behind fiber netting. Properly applied, this
system achieves a seamless blanket with uniform density while filling in
gaps behind pipes and outlet boxes. This ensures a uniform R value
throughout the wall cavity and helps control air infiltration. The result is
slightly greater than an R4 per inch which when added to the R6 to 7 of
the foam results in a conventional 2x6 wall with an R value of 25 to 26,
and more importantly, no air infiltration. We feel this combination
achieves the best ratio of price to performance currently available.
An insulated space is needed for the geothermal heat pump and the
Energy Star raters also prefer that the foundation walls be insulated (as
opposed to the basement ceiling). We installed R5 rigid foam and then
R13 batts in a 2x4 frame wall around the foundation. The attic has an
R49 blown cellulose with an Energy Star compliant scuttle cover. The
expected HERS rating is somewhere around 60 which would be a 5 stars
+ rating.
The other options for a high performance house would be a double wall
system or a structural insulated panel (SIP). Either will add considerably
to the cost. Since we are limited by current exterior door and window
technology (that is where the air infiltration comes from in a tight house),
you would need to do a real cost benefit analysis to see if these options
would pay back your investment. Of course, if you decide they do, we will
be happy to build it with you!
| A lot of the information one sees on green building focuses on the materials that go into the home. Yet the LEED rating system only allows a maximum of 8 points out of a possible 129 for environmentally preferable products. Instead, many of the needed points come from using products and systems that allow you to take advantage of the latest advances in building science. Our evolving understanding of how a home works as a unified system points to the importance of materials that aid in energy efficiency, indoor air quality, and weather resistance. |
SEPTIC SYSTEM: PRESBY ENVIRONMENTAL ENVIRO-SEPTIC
When it comes to the septic system in our Demonstration Home,
there is only one logical choice and that is Enviro-Septic. This
system has become so common that we often forget what a
break-through it is. The main component is a corrugated,
perforated, high-density plastic pipe with a series of ridges that is
covered with a mat of coarse plastic fibers. Unlike a conventional
system that treats the waste effluent over soil, the Enviro-Septic
treats effluent in the pipes before releasing leachate into the
surrounding soils. Thus it treats septic tank wastewater more
efficiently and completely.
Another major benefit is the small field size required compared to
conventional systems. In addition to saving money in fill, this allows
us to disturb less of the building site. Since the LEED point system
encourages the minimum impact on the building lot and discourages
the planting of too much grass, the use of the Enviro-Septic system
contributes to the rating.
As an added benefit, Presby Environmental, Inc. uses recycled
plastic and the units are manufactured in Whitefield, NH. Testing
shows that the Enviro-Septic lasts longer than a conventional
system which adds to the durability factor that is a cornerstone of
LEED for Homes.
-GEOTHERMAL HEATING & COOLING
-CENTRAL VAC
-NETWORKED PHONE/CABLE/AUDIO
-CENTRAL VAC
-NETWORKED PHONE/CABLE/AUDIO
| CLICK TO SEE FOR YOURSELF! |
