bookmark_borderAppliances, Redux

Way back when we finalized the kitchen design, I wrote a blog post about the appliances we had chosen for the kitchen. Well, all but one of those ended up different from what is actually in our kitchen.

The biggest difference was the cooktop. We were originally planning on a gas cooktop with appropriate vent hood for the exhaust fumes from the combustion. During the early parts of construction, we switched to a heat pump for our HVAC needs. This allowed a tighter (and therefore more efficient) sealing of the house envelope. When it came to rough-in, however, Yuval realized that this caused problems for the cooktop. In particular, the vent hood we had chosen was too powerful — the air volume it could move at max was much higher than would be replaced by natural leakage and the HRV system of our house. The end result was that we would need to switch to a lower-powered vent hood, add an extra makeup air-exchange unit, or open a window whenever we wanted to use the fan on high.

The less-powerful vent hood seemed the easiest choice, but we weren’t comfortable with that plus the high-powered gas cooktop. We investigated some alternatives, and found that we could get a quality induction cooktop plus lower-powered vent hood for a similar price to the previous configuration. The only trick was that electrical wiring was nearly done, and the cooktop needed a 50-amp circuit. Luckily that fit within our capacity, and the wire was run for the stove. We did end up with an unused gas pipe also run to the island, since that was our original plan.

Induction cooktopInduction cooking is an electric-powered cooking method that combines many of the benefits of gas (quick heat-up and immediate heat adjustment) with the smooth, sealed surface of a ceramic-top stove. We chose a Thermador induction cooktop. It has a nice, easy-to-use interface, and an auto-shut-off timer on a per-burner basis. We’ve been very happy with it. We had to replace about half of our cookware, but the result is very impressive. It boils water faster than anything we’ve used before (I estimate it takes about 30 seconds per cup of water to bring to boil). The heat adjustment is instant (a pot of water that is boiling will stop within seconds of adjusting the heat down). It is easy to keep clean (much easier than a gas stove or electric coil stove with lots of parts; and has a lot less of burned-on food than a standard electric ceramic stove). After using it for eight months, we vastly prefer induction over gas and standard electric units.

Vent hood over cooktopFor the vent hood, we chose the Zephyr Europa Roma hood, which is a simple, quiet vent hood with good lighting. It has worked well for us, and looks good in our kitchen.

The combination microwave and convection oven from Bosch is the one item that remained the same. We’ve been mostly happy with it. The convection oven works well, and has a lot of nice options. The combination microwave-oven is in reality mostly a microwave, that can also do a little bit of oven functionality. We’ve used the oven function a bit, but it is not as useful as we had hoped. The interface is also a bit awkward for consumers used to modern touch-screen technology — the buttons on the oven are touchy enough that it can be annoying to use.

Fridge in-placeWe ended up switching to a higher-end fridge from Bosch. It got better reviews, including much nicer LED lighting inside. We have been happy with it so far, although the water filter needs to be changed every 6 months, and isn’t all that cheap.

Dishwasher mostly installedPartly to take advantage of a rebate on higher-end Bosch appliances, we significantly upgraded the dishwasher. We went with this unit primarily because of the silverware tray. Instead of a basket that takes up space in the lower rack, it has a third shelf at the very top that holds each piece of silverware individually. We really like this, especially because it frees up more space on the bottom rack (though there is an optional silverware basket that can be used there). The dishwasher has been fantastic: great cleaning power, and very quiet. We have occasionally mistaken it for rain outside or a shower running upstairs.

Our appliances came from Frederick’s Appliance in Redmond. They were very friendly, had all the brands we were looking for, and very reasonable prices. The came in only slightly higher than buying from online stores (which wasn’t even possible for the Thermador cooktop), and offered much more flexibility in delivery. They were also running a special that gave us a free InSinkErator garbage disposal which is nicer and more expensive than the one we were planning to buy.

Washer/dryerDue to a recommendation from a co-worker, we switched to a washer and dryer from Samsung. We chose a front-loading washer with a nice variety of options and features. Along with the matching dryer, we’ve been very happy with these. They do a great job of cleaning, and seem reasonably gentle on clothes. The dryer has a nice auto-dry feature that figures out how long it needs to run to get a load dry. It also has a wrinkle-prevent feature that works very well.

Overall, we ended up upgrading a number of our appliances from the original plan. We are very happy with everything we ended up with, though. The cooktop, dishwasher, and washer and dryer are particularly outstanding. The long-term maintenance and life-span is something we will have to wait and see; but after eight months of regular use, everything is doing very well.

bookmark_borderGreen Home Tour

Our house will be participating in the Seattle Green Home Tour this coming weekend! Our in-progress house will be open Saturday and Sunday from 10am-4pm. One or two of the finished houses in the development may be participating, too. We’ll be hanging out there for a while each day, and would be happy to give a tour and talk about anything you’re interested in.

For address and more information, check out the page about our site.

bookmark_borderHeating & Cooling

“Can we have multiple heating zones with this setup?”

What far reaching affects this innocent question had! Our original plans for an HVAC system were fairly typical for a new home in the US: single-zone, central-air, powered by an efficient gas furnace with an attachment point for a future air conditioner coil. You can add zones to variants of this system, but it becomes increasingly complicated (and expensive). Yuval suggested that we look at heat pumps.

What is a heat pump?

A heat pump uses condensation and evaporation of a refrigerant to heat or cool a space. Air source heat pumps use the air as the energy source/sink. It doesn’t take much to get a feel for how heat pumps can heat a space:

  • Evaporating the refrigerant transfers energy from the air into the refrigerant. The loss of energy leaves the air cooler.
  • Condensing the refrigerant transfers energy from the refrigerant into the air. The addition of energy leaves the air warmer.

This may make it seem like heat pumps would require the space where the energy is coming from to be warmer than the space where the energy is going to, but this isn’t the case. The heat source only needs to be warm enough to transfer energy to the refrigerant, and the heat sink only needs to be cool enough to accept heat from the refrigerant.

Refrigerators and freezers illustrate this well. They use a small air source heat pump to make cool spaces even cooler by transferring the energy in the fridge into your kitchen (which is, hopefully, much warmer than the fridge or freezer).

For further details, you can read this article and these not-very-good Wikipedia articles: Heat Pumps, Air Source Heat Pumps. And at this point, my facts become an amalgamation of things I have read and things I have learned in conversation — sorry about the lack of citations.

Some trade-offs

Heat pumps are fairly rare in the US today. They are more common internationally (the system we are going with is from Mitsubishi), and the systems have been around for a while. They are common enough, and becoming more popular as their efficiency is recognized, that we shouldn’t have problems maintaining our system, but it is a risk.

Heat pumps, at least the ones we are considering, are driven electrically, but run at a much higher efficiency than electric baseboard heat. They are more comparable to an efficient gas furnace, but as the opening question points toward, heat pump systems are easier to configure into zones. Separately-controlled and conditioned zones are often more efficient since you aren’t heating the whole house to the same level, but just the area(s) you are currently using. The Mitsubishi system provides a number of other efficiency features, such as providing a variable amount of conditioning (instead of full-on or full-off), and less heat loss in the small, well-insulated refrigerant lines versus standard ductwork.

Heat pumps require refrigerant, and refrigerants are a negative, as far as the environment is concerned. This is partially mitigated by fact that this is a long lifetime, closed system. Mitsubishi also uses refrigerant that has a low environmental impact.

Some heat pump systems, including the one we are using, are reversible — they can transfer energy in  and act as a heater or transfer energy out and act as an air conditioner. Even though we were not planning on installing an air conditioning unit at construction time, using a system which supports both functions results in a simpler, more cost efficient solution.

No ducts! The refrigerant line is hardly larger
than the wiring, and with the wrapping
it’s still ~2″ in diameter

Heat pumps have one more really big advantage for a green home: they don’t require ducts. We are going with a fully ductless setup where the refrigerant lines run directly from the exterior units to the distribution units. This allowed us to open up the main floor by removing the need for some interior soffits. The impact on the roof was much more substantial. Because we don’t need to run ducts, our home is now able to support a roof design that provides a significantly higher level of insulation. Since the roof is one of the large energy leakers in a standard home, this will result in a much tighter home. (Sneak preview: this ended up having some unintended consequences in our kitchen.)

Our system

We are going with a Mitsubishi heat pump system. Two external heat pump units will drive six interior distribution units, for a total of six different zones (one per bedroom, two on the main floor, and one downstairs). We decided not to go with programmable thermostats since they are expensive and the units we are buying support a basic level of programmability — a single day/night cycle — that is good enough for us.

Not ugly, but not exactly beautiful

This is one of the units (installed over the door of our dressing room). The units are not huge, but they are not small either. Each unit is about the width of a doorway, and about a foot tall and a foot deep. This is fine in the bedrooms and media room, where we were able to put them in fairly out-of-the-way locations (over doorways). However, we were not able to do this in the open living area of the main floor; we put the distribution unit behind the fireplace — okay, but not ideal.

This was actually a bit of a disappointment. We initially planned to do a system that used small ducts on the main floor to move the air from the distribution units to the open space. This is when green politics got involved. We’re going for a Built Green certification on our home — this is a nice-to-have that gives us a verification that our home is green by some external standard and is also good marketing fodder for our builder. To get a Built Greet certification, your heating system must be Energy Star approved. However, Energy Star does not handle configurable systems well.

The exterior hookup.
The installed unit will only be 3′ x 3′ with a depth of 1′

Both the ducted and ductless variants of the Mitsubishi are Energy Star approved. However, what is not approved is having a single exterior unit drive one ducted interior unit and one non-ducted interior unit. Energy Star approval applies only to the exact system that was evaluated. This makes sense — variations could potentially decrease the efficiency of a system. However, approval is binary, and there is no process for getting small variants approved; the variant has to go through the full approval process, and the cost of that is prohibitive for one-offs or all possible combinations. Okay, rant over =)

Overall, we’re happy with the configuration that was installed. We’ll provide an update once we’ve moved in and have experienced how this works in practice!

bookmark_borderGreywater practicalities: Receiving

To finish up our introduction to greywater, we’ll cover the receiving system. This is my favorite part of the system. We get to think about gardens and trees!

Greywater should not be used to water above the surface (leaves, grass, etc.) nor should it be used to water food. Greywater should be used to apply below-surface watering to non-food plants. Food producing trees are an exception to the “don’t water food rule” as long as the water is applied only to the roots.

Non-pressurized distribution systems are generally well suited for sending a fairly large amount of water to a fairly small number of end points. This makes trees great candidates for greywater receivers. Trees need large amounts of water, and they can handle getting significant doses at one time.

To be most effective, trees receiving greywater should be planted in mulch basins (actually, mulch basins are generally a good idea for trees). Mulch basins allow water to be purified much more effectively than a tree just planted in the ground. A mulch basin starts with a basin with an island in the middle. The tree is planted on the island so that it does not sit in the water. The basin is filled with mulch which both prevents the greywater from being exposed to the surface and slows the flow of water, allowing better infiltration into the soil.

When greywater transitions from the distribution system to the receiving site, it should either flow into an underground chamber or directly into a mulch basin which can quickly prevent it from being above ground. This part of the system must be designed to avoid clogs, both from the greywater itself and from the material that the water is being let into (or slugs, as apparently they sometimes like to crawl up pipes).

I hope that you enjoyed this introduction to greywater. Greywater systems are not for everyone, but I hope that in the future, new homes will default to having separate collection plumbing so that more people can at least have the option of saving water.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderGreywater practicalities: Distribution

Once greywater is collected, it needs to be moved into the landscape. At its simplest, the distribution system could be a bucket that you manually lug to the relevant part of the landscape. However, such a distribution system is hard to use and has health concerns.

Given concerns about ease of use, ease of maintenance, health, and efficiency, the distribution system is probably the most technically challenging aspect of a greywater design system. As such, I’ll just cover the bare bone basics.

Most greywater distribution systems involve a series of pipes. The simplest systems take advantage of gravity to help water flow from the collection point to the receivers. These systems require the pipes to slope. The exact configuration can be finicky. If the slope is too shallow, the water will not flow. If it is too steep, the water will run ahead of the solids (lint, hair, food particles) leading to an eventual clog.

More complicated systems can be pressurized, although some pressurized systems require filtering to get rid of any solids in the greywater. Pressurized systems can move water uphill or along areas with too shallow a slope at the cost of energy and complexity. Some pressurized systems can safely water lawns by providing water underground. However, pressurized systems tend to break more easily and are significantly more expensive.

Whether pressurized or gravity driven, the distribution system should be designed with maintenance in mind. There are lots of good tips for maintainable distribution, but there are a couple key points. First, make sure you know where your pipes are (they’ll be hard to find after they’re buried). Second, make sure that you have access points for inspections, clog removal, and other maintenance tasks. Depending on how you’re using the greywater, it may also be worth designing the system to be reconfigurable in full or in part.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderGreywater practicalities: Collection

The last three posts in this series are going to get a little technical (but still not very). If you only care to know the general gist of greywater, you can stop here. If you want to know a bit more about how a greywater distribution system works, read on!

A greywater system has three subsystems: collection, distribution, and receiving. Each subsystem impacts the others, but for the sake of simplicity, I’ll consider each separately.

Collection is the process of gathering the greywater. Greywater plumbing should follow all of the relevant plumbing codes, but instead of mixing greywater and blackwater shortly after they are produced, a greywater collection system keeps the two separate. Like any major plumbing change, collection plumbing is easier to add at construction time or when you already have the walls open to modify plumbing. As such, it’s worth doing during construction even if the water initially is all sent to the sewer.

The most important factor to consider for collection plumbing is conserving fall. Fall is the vertical distance your pipe travels. Since greywater systems generally rely on gravity to move water, you want the points where your collection plumbing exits the house to be higher than for the sewer system (which generally exit under ground). Make sure your plumber conserves fall much more aggressively than they normally would.

Collection plumbing needs to have overflow into the sewer system. In addition to the overflow, it’s generally a good idea to add a manual diverter near the point where the collection pipes exit the house. This allows all greywater to be sent to the sewer if needed (e.g., if you only need the greywater seasonally). If you are designing a system that will also handle dark grey water from the kitchen sink or a diaper-washing-clothes-washer you can add additional diverters to allow selective water diversion. All diverters should be easily accessible or they’ll never be used.

In the simplest systems, water flows directly from the collection pipes to the distribution system. But not all distribution systems are equipped to handle a large surge of water (e.g., from draining a bathtub and clothes washer at the same time). A surge tank slows the rate at which water enters the distribution system.

The opposite problem can also occur: the amount of water at a particular time is not enough to effectively flow through the distribution system. In this case, a tank can collect water and then dose the distribution system with a single large flow when enough has built up. Both surge protection and dosing require care to ensure that the water does not sit too long — think a maximum of hours, not days.

Tomorrow we’ll explore greywater distribution.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderGreywater goals

There are lots of reasons to use greywater[1], and every greywater system will have a different combination of motivations, goals, and constraints. Greywater systems are not one-size-fits-all so it’s important to understand what you want before you choose a particular system.

Our primary goal is to reduce the amount of water we use in maintaining the fairly extensive gardens we hope to have. Our secondary goal is to reduce the amount of waste water we send to the sewers. Our primary motivation is practical — I hate wasting water that can be put to perfectly good use. Secondary motivations are environmental (reducing water use and sewage treatment volumes) and financial (saving on summer watering).

Because practicality is my primary motivation, we want a system that is fairly easy to maintain and fairly inexpensive to install and maintain. This means that we plan to limit myself to quantities and qualities of greywater that can effectively be processed by a garden. Since storage requires delicate and expensive filtration and purification systems, we’ll focus on a system that allows us to divert water directly to the garden when needed and to the sewer when it is not needed.

As we’ll see in the next post, these motivations, goals, and constraints make it a lot easier to decide what type of greywater system is right for us.

[1]The legality of these uses varies by jurisdiction. In general, regions in the US that do have real water problems seem to have more flexible and realistic regulations than places that don’t. Be sure to check with local regulations before building a greywater system.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderShades of grey: Greywater health and safety

Conversations about greywater often start with questions: Is it safe? What about disease? Greywater is safe, but we do need to take precautions.

First, let’s talk a bit more about greywater and blackwater:

  • Greywater: Waste water with a low level of solids and a very low level of pathogens or toxic chemicals. Sources: washing machines, showers, tubs, bathroom sinks.
  • Dark greywater: Water with a moderate level of solids or a low level of pathogens or toxic chemicals. Greywater turns into dark greywater if it sits for prolonged periods. Sources: Washing machine water used for diapers, kitchen sink water with small amounts of garbage disposal use, greywater stored too long in a tank.
  • Blackwater: Water with a high level of solids, pathogens, or toxic chemicals. Sources: Toilet water or water from a sink that has cleaning chemicals poured into it.

Blackwater and dark greywater both can, under certain circumstances, be handled at home, but it requires lots of caution and more complex systems. I plan to ignore both for the rest of this series.

That leaves us with greywater. Greywater is not very contaminated. One statistic I saw claimed that residential greywater in the US has about the same level of pathogens as drinking water in some drought ravaged third world nations. That’s not a good thing — there are very good reasons that improving access to clean water is an important philanthropic goal — but it does illustrate that the contamination in greywater is something to be managed, not feared.

The low level of contamination in residential greywater in the US can be processed by the microorganisms in the soil, but every greywater system should follow basic guidelines to ensure healthy treatment. Ludwig’s book presents two fundamental guidelines for safety:

  1. Greywater must pass slowly through healthy topsoil for natural purification to occur.
  2. Design your greywater system so no greywater-to-human contact occurs before purification.

From these general principles, many specific principles can be derived: don’t add non-biodegradable chemicals to your greywater, get it quickly into the soil, don’t use it to water food plants, don’t spray it directly on plants such as grass, etc.

But the bigger point is that when it comes to greywater, both disregard for health concerns and excess obsession with health concerns should be considered errors. Education combined with careful design and management can produce a safe home greywater system.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderWhy greywater?

We live in the Pacific Northwest where we have the good fortune of an abundance — some might say overabundance — of rain. But not all climates are so fortunate. Some parts of the world have almost constant water shortages due to degradation of the local water supply or a population which exceeds the water capacity of the region. Even in the northwest, we have to occasionally worry about drought, and no one likes high summer water bills.


On the other side of the coin, most homes in the US dump hundred of gallons of water into the sewer system every week. Some of this water is blackwater, which is any water that contains high levels of pathogens, e.g., toilet water. But the vast majority is greywater, which is water that has only a small amount of contamination, such as laundry or hand-washing waste water. Since black and greywater are mixed in most sewage systems, municipalities have to invest in expensive treatment plants which treat the whole slurry as if it were blackwater.

So here we have two problems: water shortages and sewer system load.

As is often the case, this problem can be mitigated by turning waste into a resource:


By separating out greywater from blackwater, we can reduce our residential water usage and reduce the load on our sewer systems. It’s a win-win!

In the next posts, I’ll give a high level overview of some of the concerns around greywater reuse and some practical tips about greywater systems.

In this post and throughout the rest of this series, I use Art Ludwig’s The New Create an Oasis with Greywater as my primary source; it’s considered one of the best resources on residential greywater for the lay reader. Other bits and pieces are mostly pulled from my memory of other books and websites I’ve read. Any mistakes are, of course, my own.

bookmark_borderAbout Green Building: Costs and Benefits

Green building provides a lot of benefits for the homeowner. A green home will often be higher quality and more livable because of the intentional design. It should have cheaper (sometimes much cheaper) utility bills over the lifetime of the house. Residents should have a quality of life when they are not surrounded by materials that are leaking chemicals. For those who care about such things, living in a green home leaves you with the knowledge that your home construction resulted in less waste and likely used recyclable or renewable materials.

Some of this may come at a cost — wool carpet is more expensive. Low-VOC paint may cost more because it is less common. However, other choices, such as choosing bamboo flooring over exotic hardwoods or choosing local manufactured stone, may save money. Labor costs may be higher for new construction techniques, but money is saved when less material is wasted. High performance windows may cost more, but your energy costs are much lower over the lifetime of the home (plus, you will be less impacted if energy prices rise significantly).
Green building does not have to cost more; but in practice it is rare enough that we are still paying a premium due to the limited sources of green products and the limited number of workers trained in the proper building techniques. If nothing else, most green buildings probably have more time and effort put into design than a standard home, and that will increase costs. However, we think the cost will definitely be worth it for a better home in the end.