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Building a “Green” Home - Inside and Out
The LmP House
Summary
K & P Contracting Ltd. is known throughout the residential construction industry as a
leading R-2000 and EnerGuide builder, having built the first R-2000 home in Newfoundland
and Labrador in 1982. Now they are breaking ground again as the builder of the first
Net-Zero, LEED Gold Certified, Energy Star Registered home in the province.
The planning and design of this state of the art new home, the execution of novel
approaches in both the exterior and interior construction, energy efficient and
environmentally friendly appliances and finishes all combined to reach the goal of building
a truly “green” home.
K & P Contracting Ltd
K & P Contracting Ltd (K & P),was started by Jack Parsons and Francis Keating in the
1970s. Since then, they have always been in the forefront of the industry when it comes
to high quality, energy efficient homes. Recently, K & P became a 2 generationnd
company with Wayne Keating and Curtis Mercer building on Jack and Francis’ past
successes, and preparing to take the company through the next 37 years. Dr. Clifford
Stamp is also a key member of the team - adding to the technical evaluation and design
of the projects. Quality contracting, durability and customer satisfaction continue to be the
primary focus for K & P, as they provide a complete building service, design - manage -
build, to new construction or renovation projects.
The Beginning
Jack began designing and planning the home for his daughter, Laura Parsons (LmP), in
the Fall of 2013. Being a chemical-environmental engineer, she had a strong desire to do
something more than just meet the National Building Code (NBC) and even
R-2000/EnerGuide Standards. That gave Jack the push he needed to go above and
beyond what had been done before and build a house that was able to meet the goals of
a triple bottom line - environmentally sustainable, economically feasible, and socially
acceptable for the homeowners.
Planning for Innovation
The first step, and the key to success, in designing and building something that hasn’t
been widely done before is developing a detailed project plan and getting all stakeholders
involved from the beginning. It is vital to ensure that all systems work together and details
are combined to meet the overall end goal of an energy efficient product that meets all the
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 2 of 10
homeowners needs and wants. Optimum Value Engineering (OVE) was used to ensure
each aspect of the build was able to maximize value to the project while minimizing waste
and cost.
Communication has been key from the beginning to ensure that everyone was on board
with taking on this project and the challenges that come with it. The team at K & P
including Jack, Francis, Curtis, Wayne, Cliff and others were ready and willing to work with
the homeowners to design and build a house that would not only meet their family needs
while maintaining and enhancing street appeal but also far exceed the environmental
standards of a traditional home. For the homeowners, this meant some additional cost but
nothing that wouldn’t pay itself off over time due to added savings in energy, water, or
material life cycle costs. This house encompasses the whole picture of a triple bottom line
approach.
The design and planning process included a complete review of all aspects with regards
to both a life cycle cost analysis and simple payback. Products and design were analysed
to determine the best payback for increased energy efficiency while also taking into
account any added cost, maintenance and the energy savings payback period. K & P
considers the principal of OVE in all builds, and has attempted to take it to the next level
on this project. For example, the building envelope has reduced the size requirement of
the heat source and provided significant savings which more than balance the added cost
of insulation and framing.
Each decision was made while looking at the details of each component as well as the
house as a whole. A house works as a system such that small changes in one aspect of
the design can have a larger impact on another. For example, choosing which appliances
to use will impact the energy load, the kitchen design, heat requirements, and other
aspects. Similarly, the design of the insulation, ventilation, and thermal envelope all
needed to be evaluated in conjunction with each other. Multiple energy models were ran
using NRCan’s HOT2000 building energy simulation tool to determine the best options for
energy conservation. The design evaluation often involved initial design and subsequent
re-design to ensure all components worked well together. For example, after choosing the
initial floor plan, the insulation plan was done which increased the wall thickness
significantly. This meant some re-design to accommodate for this extra space. It is
imperative to pay close attention to this planning stage – there is no cost to making
changes on paper, but making changes later can have large financial and schedule
implications.
One of the most important considerations for this home was the functionality and
practicality – it is a family home, meant to be lived it. The homeowners wanted to ensure
that the design of the home would be able to meet their current and future needs. Whether
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 3 of 10
it was to make the house more comfortable, add to the street appeal, or help make the
house ready for their future family, each decision was made with purpose.
The investments made in building this home were carefully evaluated to find the best
options from an economical, environmental and social perspective. This meant that each
choice was cost-effective, environmentally responsible and, of course, able to meet the
needs of the home owner. One main goal in building this house is to provide an example
for others to build more sustainably and more environmentally friendly, without breaking
the bank.
Energy Modelling
Throughout the entire planning process the energy demands and green house gas output
was modelled using HOT2000 (H2K). H2K was developed by CanmetENERGY's Housing,
Buildings, Communities and Simulation (HBCS) group and has undergone over 23 years
of consistent development to become the Canadian standard for evaluating the energy
performance of residential buildings. It is used in over 150 countries, and produces more
energy evaluations of houses than any other equivalent software tool.
Each aspect of the house, from the basic wood frame structure, to the insulation type and
methods of application, the details of the heating system, the appliances chosen and the
type of lighting used, were continuously added and updated in the H2K model to ensure
that their impact was studied on a holistic level with the greatest accuracy and precision
possible.
Execution
The first step in any new construction project is choosing the location and land. Any area
has positive and negative considerations, especially when trying to optimize passive solar
gain. The key components to consider include the orientation of the house, natural
vegetation, street appeal, and, of course, the neighbourhood. South facing windows will
give the most solar gain so it is important to pay attention to direction when choosing the
orientation of the home. In addition, wind protection should also be taken into account as
it can reduce heat loss.
For this home, the land was previously owned by the home owners. It was shielded from
the wind but the vegetation was limited. When clearing the land, the goal was to keep as
much natural vegetation as possible; unfortunately, in this case, it was mostly low-lying
bushes and shrubs so there wasn’t much available. The land did provide south-east and
south-west (and some south and west) sun exposure which could be utilized for passive
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 4 of 10
solar gain.
The excavation had to be effectively planned and designed since the site had a high water
table. Francis, using his 40 plus years of experience, provided the balance between the
house plan, site work and the project planning. The derived balance is a 4’ (3’10”)
concrete foundation wall with a 5’ (4’9”) wood knee wall, see Figure 1, an enhanced K &
P Building Detail.
The house is being serviced by a drilled well and a septic system which had to be
accounted for during the excavation. In order to have a long term, trouble free septic
system, an in-house lift station was installed which allowed the disposal field to be installed
at a higher level. Fill, with a
percolation rate of 9 minutes,
was used to ensure that the
system will last for an extended
time frame with minimal
maintenance requirements.
Next the foundation, using a
fairly standard design. R & L
Contracting Ltd. installed an 8"
thick concrete wall, 3'10" high on
top of the previously installed
4'”'x16" footings. The foundation
was insulated with mineral wool
(Roxul) insulation to a rating of
R-28. The makeup was an 8"
concrete wall with dampproofing
on both sides and a double layer
of R-14 insulation. The interior
wall used 2x4 studs at 24" O.C.
and a standard 6 mil poly air
vapour barrier (AVB). A 3"
concrete slab was installed by
Firmini Concrete Ltd. over the
radon barrier, 2" rigid insulation
(R-8), 1" pea gravel, and 4"
washed stone. The main section
was finished with acid stained
concrete to allow for passive
solar heat storage.Figure 1. Wall Section.
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 5 of 10
The knee walls, a new design from K & P, included (exterior to interior) 7/16" OSB wall
sheeting, 2x4 studs at 16" O.C., two layers of R-23 batt insulation followed by 6 mil sealed
poly AVB. The inner wall was built with 2x4 studs at 24" O.C. and R-14 batt insulation.
Thermal bridging has been prevented by the offsetting of studs in both walls. The walls
were finished with ½” drywall. This innovative design gives the knee walls an overall
insulation rating of R-60. Figure 1 depicts this simple but effective innovation.
The floor is a conventional design, timber frame supplied by Hickey’s Timbermart. The
joists are 2x10 dimensional lumber, framed at 16" O.C. with a glued and nailed sub-floor
of 5/8” OSB. 1x3 strapping was used at the midpoint in the unfinished section of the
basement.
The main walls are also part of the K & P innovation to give an overall insulation rating of
R-42. The lay-out included vinyl siding with a house-wrap membrane over OSB wall
sheeting ensuring long term building durability. R-14 batt insulation was used with 2x4
studs at 16" O.C. followed by an R-14 batt insulation installed on the horizontal with 6 mil
sealed poly AVB. A second interior wall used 2x4 studs at 24" O.C. with a third layer of
R-14 batt insulation and ½” finished drywall. This three layer approach with staggered
studs prevents thermal bridging and ensures minimal energy leakage from the home. The
sandwiched AVB eliminated over 100 penetrations into the system. The plan is to achieve
an air tightness value of less than 0.5 air changes per hour (ACH) at 50 pascals.
The triple glazed double Low E argon gas windows were installed using K & P’s building
detail (KP-100). The detail was designed to adhere to the install instructions as per
Section 27 of the NBC, and can increase the seal between the house-wrap building
membrane and the window. This is designed to eliminate any water infiltration around the
window and to ensure durability. Due to the high wind and rain encountered throughout
Newfoundland and Labrador, it was felt that this additional level of protection would add
significant value to the building system.
After the window opening is framed to the rough stud opening (RSO), a sloped sill is
installed, 1x4 strapping ripped diagonally to allow a minimum of 6% slope. Building wrap
is installed across the bottom and stapled to the sill then two strips, one on each side,
overlapping the previously installed strip on the bottom. A small strip is then installed
across the top of the RSO. A peel and stick (P&S) membrane is then installed across the
bottom of the RSO so that it overlaps the sloped sill and allows for drainage. Each bottom
corner is sealed with additional pieces of the P&S. A single bead of high performance
sealant (chaulk) is ran around the other 3 sides of the RSO. The window is installed and
shimmed to ensure it is centred, level and square.
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 6 of 10
A 4x6 piece of P&S membrane is installed on each bottom corner and a 4" strip is installed
up each side, extending 5" above the top of the window. A 6" piece of P&S membrane is
installed across the top of the window extending 6" past each corner. This process has
proven to provide an extremely durable and tight window installation to prevent against any
water penetration.
The windows were designed with the
assistance of Anil Parekh with Natural
Resources Canada. An analysis was
conducted of four window options,
combining double and triple glaze, Low
E and double Low E Argon gas as
options. The results determined that
through the use of double Low E, triple
glazed windows filled with argon gas, a
gain of 2.3 GJ was possible (see Figure
2 and Table 1). This meant a 17%
reduction in space heating energy
needs. The windows were
manufactured by ACAN Windows and
Doors, and supplied through Hickey’s
Timbermart.
The roof was designed with major input
from Spencer Morgan of Terra Nova
Trusses in an original K & P design
including roofing shingles, roof sheeting
and R-70 insulation. The end cavity in
the eave used rigid insulation while the
rest was blown in cellulose insulation.
The trusses are pre-engineered at 2'
O.C. A 6 mil seal poly AVB was installed
with only one join above the 2x2
strapping to allow for electrical
components to be installed with minimal penetrations through the AVB. The heel height
(21") and overhang were specially designed to maximize passive solar heating – increasing
solar gain in the winter while minimizing it in the summer. The roof design also included
determining the optimum slope to add solar panels in the future while giving the aesthetic
appeal that was desired. The main roof is 5/12 slope with southeast exposure. The
garage roof maintains the same hip exposure but was decreased to a 4/12 slope to allow
for a kitchen window to be installed and for future planning of the rear deck and sunroom
Figure 2. Space Energy Consumption for Different Window Options.
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 7 of 10
(see details below). The shingles are an extended 30 year lifetime laminate shingle,
offering a higher durability to wind and element damage. Roofing shingles were supplied
by BP.
The main exterior doors were custom-built by K & P to achieve an insulation rating of R-22.
This incorporated a wooden shell filled with 1.5” aerogel spaceloft. Side lights in the front
entry system were designed by ACAN with the same triple glazing as the other windows
in the house.
The house exterior was accentuated with conventional vinyl siding with wood trim as well
as a stone accent using conventional cultured stone. The front entrance also included a
verandah and step with stylish railing. This gave the home exceptional street appeal and,
most importantly, appealed to the home owners.
The rear deck was also constructed after significant planning and design. As with the
house, the future uses of the rear deck were discussed to determine the possibilities for
adding to the overall efficiency of the home. The large deck, 12' X 14', was structurally
designed to be converted into an enhanced sun room that would utilize the maximum
passive solar gain possible. To accommodate the 6" planned concrete slab, the structure
of the deck was magnified to carry this load. The location was also chosen with the
passive solar gain in mind with glazing from east to west. The majority of the glazing being
on the south side was optimized to allow for the maximum daily solar intake. The slab will
have liquid fill piping embedded to move the energy from the concrete heat sink to the
interior of house.
Building a Home
The exceptional energy efficiency and improved thermal envelope design of the house
exterior is matched by the improved installations and amenities inside the home.
The building envelope described previously allows for a non traditional heating source to
be used within the home. The heating and ventilation needs will be met using two 12,000
BTU Art Cool Prestige mini split heat pumps by LG, supplied by Steers HVAC/P. These
units are high efficiency (11.5 HSPF), ultra-quiet (sound pressure as low as 17 dBA on the
indoor unit and 45 dBA on the outdoor unit), and low temperature operable (functions in
environments as low as -25 C). One unit will service the main floor and the other willo
service the basement; also allowing for a back-up in case of problems. Both units are
strategically placed to maximize the efficiency and heating consistency which increases the
overall economics of the project. The ventilation will be provided through a 195ECM, a high
efficiency unit produced by LifeBreath and supplied by Steers HVAC/P. This unit features
a cross flow aluminum dual core and an ECM motor for maximum heat transfer and
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 8 of 10
minimum power requirements.
The hot water heater utilizes a traditional, highly insulated, conserver water tank. A
passive drain water heat recovery (DWHR) unit will be used to preheat the water from the
pressure tank. The main limitation of traditional DWHR units is that unless the hot water
heater calls for water at the exact same time that the waste water is being discharged,
there is no energy recovery. The unit chosen for this application features a small storage
tank to hold the hot waste water until it is needed available for pre-heating any time the hot
water heater calls for water. In the future, the sunroom can be utilized to provide additional
heating coils to preheat the water from the pressure tank through the passive system.
The electrical and lighting system will utilize all LED light bulbs, including Smart LED pot
lights supplied by McLoughlan Supplies. In addition to the added energy efficiency, the
innovative design of the LED pot lights improve over traditional pot lighting by limiting
penetrations through the air vapour barrier membrane. Ms. Jackie Martin at Lighting World
also assisted in optimizing the lighting plan for the home to use the appropriate amount of
lighting – minimizing waste while ensuring there was adequate lighting throughout the
house.
The basement floor is a finished concrete, acid stained design by Firmini Concrete–
providing a pleasing aesthetic appearance as well as an effective heat sync to further the
passive solar design.
Figure 4. Main Floor Layout.
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 9 of 10
Many of the other interior finishes are conventional, incorporating sustainable options and
green thinking wherever possible. This includes:
• Local materials used wherever possible
• WaterSense fixtures and low-flush toilets used to decreased water consumption
• All appliances are Energy Star certified
• Kitchen cabinets, floor coatings and paints are VOC and formaldehyde free
• Smart power consumption to reduce “phantom loads” due to standby power
• Optimal ventilation for improved interior air quality
• Rainwater collection for garden use
• Sustainable materials, including FSC certified wood, used wherever possible
• Responsible management of waste construction materials
• Advanced framing techniques utilized for interior walls
• Elimination of fire place to prevent the additional heat loss
• Sealed entrance from the garage to prevent exposure to air emissions
• Oversized windows increase the natural light in the house, especially on lower level
• Flooring selection chosen to reduce chemicals emitted to the air
• Sustainable flooring products are used as much as possible
• All hot water lines insulated to reduce heat loss
• The heating equipment, HRV and hot water tank properly sized to reduce waste
• Dimmer switches and light sources matched to the task to reduce lighting loads
• Natural vegetation eliminates the need for extensive watering and maintenance
Future Planning
The home is being built to allow for future environmental optimization as well. Allowances
will be made for the house to be solar/wind power ready, with the goal of being a Net-Zero
energy consumer. This means that the homeowner would be able to put energy back to
the grid when over-producing, and to offset when under-producing energy. At present
neither Newfoundland Power nor Newfoundland Hydro allow Net Zero metering. In order
to meet the economic goals of the home as well as environmental benefits, a change in
these policies is important for the future planning in this Net-Zero home.
Building a “Green” Home - Inside and Out April 2014By: Laura Parsons, P. Eng Page 10 of 10
A Truly “Green” Home
This family home is built with the goal of meeting the standards set out by the Net Zero
House through the NRCan Net Zero R2000 Energy Pilot, LEED Platinum Certification,
Energy Star, and an Energuide rating of 100. K & P Contracting has partnered with
Memorial University of Newfoundland, College of the North Atlantic, and a variety of
dedicated sub-contractors to make this project a success – both for the new home owners
and for the environment. The goal is to minimize the environmental and energy impacts
while achieving the aesthetic and functional goals of the occupants and maintaining a
modest budget - a true representation of the triple bottom line approach. All these things
combine to provide a truly next generation living experience.
References:
K & P Contracting Design Publication
Tex McLeod
Green From the Ground Up – a Builder’s Guide, David Johnston & Scott Gibson
CHBA - The Better Built House
NRCan - Keeping the Heat In
Net Zero Energy Home Coalition
Figure 5. 3D Rendering of the Home.