Tour Our House Tonight


What: Design Mix Happy Hour at the Ballard Zero-Energy House
When: Tuesday, June 21, 4:00 – 6:30 p.m.
Where: Please RSVP for address
Cost: Free

I have recently taken a job as membership programs manager with the Master Builders Association of King and Snohomish Counties. One of my duties is to manage several of their councils programs, including the Design Professionals of the Sales & Marketing Council. Some members of this council expressed an interest in net-zero-energy home building and design, so I offered to host their monthly happy hour series, Design Mix, in my home.

The event is free and open to the public. Come take a tour of the house, while mixing with Seattle-area architects, designers, and building industry folks. Todd Bell of Premier SIPs, the manufacturer of the panels that our house is framed with, will be giving a short presentation on this building method. Refreshments will be served.

Eventbrite - Design Mix Happy Hour - Ballard Zero-Energy House

Registration is free, but I encourage you to make a donation to the Code Innovations Database, a resource for code officials, the building industry and the public to share information about successfully permitted projects and evolving green codes. CID is raising money to conduct a detailed case study of the Ballard Zero-Energy Home.



Passive House Versus Net-Zero-Energy House: What’s the Difference?

Passive House

Our builder, Ted Clifton, just finished his latest house in Leavenworth, WA. We were disappointed that we had to miss the housewarming party, but from the photos, it looks really cool.

Unlike our net-zero-energy house, this new one follows the stringent Passive House standard, developed in Europe.

The hallmarks of a Passive House are super-high levels of insulation, a design that takes advantage of passive solar gain, and, as a result, has little need for heating beyond that provided by the sun, warm bodies, and appliances. Passive Houses also come with a list of requirements, like a heat recovery ventilator, a somewhat costly piece of equipment that recoups some of the energy that would normally be lost from circulating fresh air through the house.

Are Passive Houses better than net-zero houses? It depends who you ask.

We opted for the net-zero approach because producing as much energy as we used over the course of a year was our first priority. Passive Houses can be net-zero, too, but it’s not required by the standard, and it adds to the building costs.

Upstairs Passive HouseThe focus of Passive House design is to reduce the amount of energy required to heat and cool the house (by up to 90%), whereas the focus of a net-zero house is to offset 100% of the power required to heat, cool, light, and run the home. In any given moment, a net-zero house like ours might be using slightly more power than a similarly sized Passive House, but it would make it all back from its solar panels over the course of a year.

Passive Houses tend to cost more to build since they have even more insulation than a typical net-zero house. Critics of the PH standard point to diminishing returns. To chase after that last little bit of air tightness and insulation to bring a house up to the Passive House standard can be expensive, and, in many cases, the potential energy savings could be easily and much more cheaply attained by adding a few solar panels.

On the other hand, Passive Houses are elegant in the simplicity of their mechanical systems. Some of them require so little auxiliary heat that they can be warmed solely by a cheap little wall-mounted electrical heater, eliminating the need for costly heating systems. Proponents of Passive Houses point to the fact that mechanical systems eventually wear out and solar panels stop producing as much power over time, while a well-built, well-maintained house can last hundreds of years.

Boulder TableDuring our first winter in our house, we spent a lot of time tweaking the radiant heat system, and our heat pump required a replacement electrical board (under warranty, but still a hassle). The reality is, however, that many Passive Houses, especially larger ones in colder climates, also make use of heat pumps. And, if you’re interested in achieving net-zero-energy, you’ll need to install solar panels and an inverter on your Passive House.

Looking back on it, we wouldn’t have turned down the extra insulation the Passive House standard calls for, but not if it had required us to have smaller windows or forgo our net-zero-energy goal. By not strictly limiting ourselves to the rigid standard, we were able to achieve net-zero much cheaper.

Either way, both types of house save lots of energy, and I’m happy to see them being built. Plus, Ted’s newest project is just plain cool. Check out the sliced-off boulder table in the middle of the room!

Check Us Out in Home Power Magazine

Check out the latest issue (August/September) of Home Power magazine for an article on net-zero construction and an in-depth profile of our house. I thought it was interesting that of the three true net-zero houses featured (a fourth relied on wood heat), ours was by far the least expensive at $237,000.

One house, although substantially smaller than ours, cost $575,000 to build, and the other, nearly the same size as ours, cost $550,000. These two houses, both built in Alberta, Canada, are very attractive and incorporate some cool features, like solar panels mounted on adjustable awnings and a rooftop deck (as seen on the cover of the magazine). However, with price tags of about double what it cost to build our house, they are probably out of reach for most people, especially first-time homebuyers like ourselves.

Nevertheless, it’s great to see the press covering this type of building, and I encourage anyone who is interested in living in a house like this to read the article and see the very different ways the featured projects achieved the net-zero goal.

We’ve Blown Past Net-Zero! Now How Much Surplus Power Can We Produce?

Exciting news! Despite the unseasonably cloudy summer we’ve been experiencing here in Seattle until recently, we achieved net-zero almost three months ahead of schedule.

Our net meter (the one that goes forward or backward depending on whether we’re using more power than we’re producing at any given moment) now reads 99,690. No, that doesn’t mean that we’re in for a whopping electricity bill. Rather, it means that the meter has been running backwards so much that we’ve actually gone past zero and into negative territory for the year.

What’s more, we still have many days of sun left before we reach the critical 12-month mark. Our meter hit zero on August 2, and in the last two weeks, we’ve already produced 310 kilowatt hours more than we’ve used. We have more than eight weeks until October 22, which will be exactly one year since the meter was first installed. If we keep going at this rate, we might be able to record a surplus of nearly 1,200 kWh for our first year!

What all this means is that the house is performing way better than expected. In fact, we couldn’t be happier.


Our meter registering a big 1, just moments before it dipped below zero. It’s been running mostly backward since its all-time high of 3,022 in May.

Keeping Relatively Cool

In addition to producing a surplus of power, the house has also passed another test. We were a bit worried about how comfortable it would be in the summer given the passive solar heat gain from all the south-facing windows. Having sunlight and free heat streaming through our windows is great in the winter, but would we find ourselves baking in our personal greenhouse in the summer?

We were pleasantly surprised to find that Ted Clifton Sr. had designed the eaves to let in lots of light when the sun is lower in the sky in the winter but to block nearly all of it during hot summer afternoons, when the sun is higher in the sky.

While we could technically run our heat pump in reverse and chill our floors, we’ve kept the house pretty comfortable during the hottest days (not that we’ve had many this summer) using some common sense and a simple trick Ted taught us.

We leave the windows open to let in the cooler night air and turn on the exhaust fan in the kitchen (which also activates a powered HEPA ventilation system) for about 15 minutes first thing in the morning. When the outside temperature starts to rise past what it is inside, we simply close all the windows tight and lower our double-honeycomb cloth blinds, and the temperature stays low without any air conditioning.

Right now, for instance, the outside temp is 86 degrees, while inside it’s a comfortable 75. (I haven’t even bothered to turn on the ceiling fan in my office in the loft yet.)

Room for More

Even though we’ve gone past net-zero with our current solar panel array, we could be producing even more power. We currently have twenty-eight 230-watt Solar World panels covering about two-thirds of the roof. We still have room for about sixteen more. This would give us more than enough power to run an electric car.

While on a backpacking trip last weekend, I stopped in Skykomish and noticed a high-speed electric vehicle charging station in front of a deli. The woman who worked there said that lots of people use it and that it takes about half an hour to charge up a car like the Nissan Leaf. Best of all, it’s free for now.

I had kind of dismissed electric cars because most of the driving we’d do would be to get out of town for hiking trips and things like that, but knowing there are charging stations like this on the way to the Cascades changes things a bit. Suddenly, the idea of paying nothing for driving, even on longer regional trips, seems pretty attractive.

Skykomish Electric Vehicle Charging Station

Top 10 Questions about the Ballard Net-Zero-Energy House

1. What do you mean by net-zero energy?

Quite simply, this means that our solar panels produce as much electricity over the course of a year as we use for heating, cooking, lighting, and other household tasks.

2. Are you off the grid?

Eric Thomas Ballard Net-Zero-Energy House PV ConnectionNo. While we produce our own solar electricity, we’re still connected to the city’s electrical grid. We don’t have a bunch of batteries in the basement (actually, we don’t even have a basement). Why? Because storing electricity is inefficient, not to mention expensive. When you charge a battery bank, you don’t get as much electricity back as you put in. Some of it is lost as heat. That’s why most houses that have solar panels hooked up to a battery bank must rely on some other source for heat, like a wood stove.

3. So does all your power come from the sun?

People often ask us questions like this: “If you’re connected to the grid, you’re still using dirty power at night and on cloudy days, right?” The answer is–sort of, but not really. It’s far more efficient and cost-effective to hook our solar panels up to the city’s electrical grid. That way we can put power into the grid during sunny days, when we’re producing more than we can use, and take it out at night and when it’s cloudy. It’s like we’ve set up our own little clean solar power plant, which means less natural gas needs to be extracted and burned and less electricity needs to be generated, avoiding all the associated negative environmental consequences. We like to compare it to a bank. When you have an excess of cash, you make a deposit. For all practical purposes, it’s still your money when you go to withdraw it from the ATM later, even if it was mixing with everyone else’s money on the bank’s balance sheet.

4. Does solar really work in Seattle?

Yes! Although we receive fewer hours of sunlight over the year, solar panels are more efficient in cooler places like the Pacific NW. Our long summer days more than offset our overcast winters. And, the fact is, our panels are still producing up to 1,000 watts on cloudy days. Even after installing 28 panels (enough to meet all our household electricity needs), there’s still room on our roof for enough additional panels to power an electric car over 5,000 miles per year.

5. What features allow you to achieve net-zero energy?

Our house was designed from the ground up to take advantage of the sun. Its passive solar layout means we have lots of windows facing south and few on the north side of the house. The house itself is built from structural insulated panels (SIPs), manufactured in Fife, WA, by Premier SIPs. An air-to-water heat pump, manufactured by Unico in St. Louis, lets us heat water for our radiant concrete floors and domestic hot water at over 200% efficiency. Triple-pane vinyl windows by Vinyltek were a cost-effective way to bring in lots of light and passive solar heat without losing much heat at night. We also made sure to select some of the most energy-efficient appliances on the market. By conserving energy as much as possible, we are able to offset all our electricity usage with a 6kw solar electric system, installed by Sunergy Systems in Ballard.

6. What other “green” features did you incorporate?

We incorporated reclaimed materials, including wide-plank fir floors from Salisbury Woodworking on Bainbridge Island, a cast-iron tub from Craigslist, a cast-iron kitchen sink from Second Use, and other items. Our water-saving dual-flush toilets with a sink on top are definite conversation starters. We also have a rain barrel system made from old oak wine aging barrels (contributed by our builder, TC Legend Homes) which feeds all roof runoff into a large rain garden in the backyard. We have an active HEPA filtration system to provide fresh air and filter out allergens. And the house was engineered for low waste, which meant we never had to have a dumpster on site during or after construction.

Eric Thomas Ballard Net-Zero-Energy House Water Barrels Eric Thomas Ballard Net-Zero-Energy House Kitchen Remodel Eric Thomas Ballard Net-Zero-Energy House Kitchen Remodel

7. Can I build a net-zero house of my own?

That would be great! We’ve been trying to show our house to as many people as possible in the hopes that we will inspire others to build to the net-zero standard. We started by finding stock plans on, and our designer, Ted Clifton Sr., modified them slightly to suit our small city lot. We chose Ted’s son, Ted Clifton Jr., of TC Legend Homes, to build the house because of his experience with SIPs construction and because he’s a good guy. The building process was a lot of work for us, mainly because we took on some extra tasks, like pulling all the building permits and installing the wood floors ourselves. The actual building went quickly. In fact Ted and his crew of about three finished building a month ahead of schedule!

8. Can I convert an existing house?

Yes! Obviously, there aren’t too many empty lots left in Seattle, so retrofitting is going to play an important role if our city is serious about reducing its home energy use on a large scale. Luckily, there are lots of ways of making older homes much more energy efficient—and even achieving net-zero. You can start by adding insulation and sealing leaks and go all the way to wrapping the entire structure in SIPs panels and covering the roof in solar panels. Every little bit helps, and it’s often the simplest, least costly retrofits that have the biggest impact.

9. So how much does all this cost?

Out of necessity, we went into this project with the goal of keeping the cost of our new house about the same as the price of a townhouse in the neighborhood. The cost of the land was $180,000, and construction, solar panels, taxes, and permits added another $237,000. After a $9,000 federal rebate for the solar panels, and an approximately $9,000 WA solar production credit (paid out over 9 years), the grand total came to about $399,000. We were pleased because the cost to build was only $124 per square foot ($114 if you count the rebates and incentives), whereas the average in Seattle is $200 per square foot. Plus, we won’t be paying for energy, which comes to about $150 per month, or $1,800 per year, for the average Seattle household.

10. Should I do this?

Absolutely. Go for it! Building this house has been really rewarding for us, and we’d love to help others pursue the net-zero-energy goal. So feel free to get in touch with us if you’re thinking about it and have questions.