Habitat for Humanity in Whatcom County offers a hand-up, not a hand-out, to families striving for a path out of poverty. We work in partnership with low-income families to build simple, decent homes where they can live and grow into all that God intends.
We volunteer, donate, advocate, pray, and work in partnership with our community.
With hands and hearts, hammers and nails, we are building a world where everyone has a safe, decent, affordable home. Join us!
Question: When I buy an item from the Habitat for Humanity store, where does that money go?
Answer: That money is used to construct homes right here in Whatcom County. Habitat for Humanity builds homes using a “Passive House” design.
Q: What exactly is a “Passive House” design and why does Habitat for Humanity use it?
A: We have set out to build the most efficient homes possible so that homeowners pay next to nothing for utilities. Building homes that meet the standard set forth by the Passive House Planning Package translates to a home that uses 60 to 70 percent less overall energy than a typical code-built home. The savings are even higher when looking at specific costs (e.g., heating and cooling) that are estimated to be 90 to 95 percent more efficient than code-built homes.
A Passive House focuses on the house as a complete, airtight, highly insulated system that uses a very low level of energy per square foot while also improving the home’s indoor air quality. Here comes the science! The Passive House standard requires that a home have a heating load no greater than 1.4 kilowatt-hours (kwh) per square foot per year, the same standard for a total cooling load, and a total annual source energy consumption not exceeding 11.1 kwh per square foot. To get a better idea of what that means, let’s take a closer look at the numbers for space heating.
To meet the Passive House standard, a 2,000-square-foot home would need to use less than 2,800 kwh for space heating a year. The average U.S. home uses the equivalent of 11,800 kwh for space heating, according to the most recent figures from the U.S. Energy Information Administration.
Q: What does all of that mean?
A: Find a hair dryer and turn it on. The amount of power used by that dryer is the same amount of power it takes to heat or cool the entire home.
Q: How can an entire home possibly be that efficient?
A: The best way to answer that question is to answer is to provide a drawing—
It looks like a lot to learn but when you break it down, the process is quite simple to understand.
Reducing Air Infiltration
When constructing a home under a Passive House Design, builders focus on reducing air leaks by sealing up areas in the home susceptible to leaks. These areas include the basement, walls, floors and ceilings, gaps around windows and doors, and through leaks in the ductwork. Air can also move between insulated and uninsulated areas within the home so that heated (or cooled) air is constantly being lost. This is called Thermal Bridging, which will be discussed in just a moment.
The International Residential Code’s current energy code allows for a maximum 7 air changes per hour (ACH) at 50 pascals (a measurement of pressure). In simple English, that exchange refers to outside forces interacting with the internal pressure of the home, resulting in heated or cooled air escaping outside. A home that has met the Energy Star requirements allows 5 or 6 ACH depending on the climate. In contrast, a Passive House air infiltration standard is no greater than 0.6 ACH, meaning Passive Houses are almost 10 times more tightly sealed than Ef
It should come as no surprise that a home without insulation is a home that is cold when it’s cold out or warm when it’s warm out. The better insulated your home is, the more you can slow down that heat movement. Passive Houses rely on thick, properly installed wall and ceiling assemblies. Each home is unique in terms of how thick insulation needs to be to meet the Passive Home standard. Keep in mind that insulation is one of the least expensive building components.
Eliminating Thermal Bridging
When heat is able to pass through uninsulated areas, it’s called thermal bridging. Most thermal bridging occurs through the house framing, but other uninsulated areas may be found around concrete foundations, combustion appliance venting, fireplaces and plumbing vents. When we mention “uninsulated” areas we are talking about possible links directly outside To minimize thermal bridging builders make sure to insulate under all interior concrete slabs using exterior rigid foam assemblies and double wall framing.
High-Performance (and Properly Placed) Windows and Doors
High-performance windows and doors will likely be the highest additional cost in constructing or remodeling to the Passive House standard. Usually, triple-pane windows or heat mirror technology will be required to meet the standard. Triple-pane and some double-pane window designs for efficiency include an insulating layer of either Argon or Krypton gas.
Super-Efficient, Balanced Ventilation Systems
The final critical element of a Passive House is using a high-efficiency heat exchanger and a balanced mechanical ventilation system to supply occupants with the ideal amount of clean, fresh air (“Balanced” simply means that approximately the same amount of air exits the house as enters the house).
What is unique about this setup is that a Passive House can recycle all internal heat gains, including body heat from occupants of the house; other sources of heat from appliances is also factored into this equation. With a super-tight shell and a 95 percent efficient ventilation system, much of the home’s heating and cooling needs can be fulfilled passively, and then only smaller and less expensive heating and cooling systems are necessary. Some of the popular heating system choices for Passive Houses are heat pumps, solar thermal systems and electric baseboard heaters.
The Youth United Build is gearing up to start construction on a new home for Dan and Mary VanDyken to be located on Haxton Way.
Under the Youth United banner, more than a hundred students from Squalicum High School will begin the build. Collaborating with these young people are teams from both the Building on Faith and Women Build programs, creating strong community partnerships, teamwork and lasting friendships.
The two-bedroom 900 sq. ft. home is being built using the “passive” design, which sandwiches 12 inches of densely packed cellulose R42 insulation between an inner and exterior wall. This design eliminates the possibility of exterior air coming in contact with the interior of the home, making it extremely energy efficient. The cost in materials and labor tack on approximately $15,000 to the build, but energy costs will average between $20 and $35 per month for heating and cooling.
The VanDykens currently live in a rustic, uninsulated home in Glacier that does not provide them with a safe place to live. Dan, who suffers from a chronic illness, and their grandson Cody, who has asthma, will no longer have to suffer from living in an environment of substandard housing.