My parents came to visit this weekend, so I borrowed my dad's camera to take some interior shots (the wide-angle lens on my iPhone is a bit sub-par).
Yes, the house is a mess. We just moved, after all! If my mom could handle it, I'm sure you can.
Here's the main downstairs view, just after you walk in the front door. The curved staircase is from York Spiral Stair in Maine.
And here's the same view from one floor up. It's a little hard to see in the photo, but the ceiling vaults upward toward the south windows. The closed-off area on top is a utility loft containing our solar inverter and heat recovery ventilator.
The 2x4 barnyard-style railing around the atrium is temporary — the eventual railing will match the stair railing and balusters.
Below is the opposite view, taken from the office area below the utility loft. The windowy area on the right (with the uninstalled door) will be an indoor garden space, taking advantage of the eastern and southern exposures. The clerestory windows along the hallway will bring south light into the guest bedroom.
Here's a view from the bedroom at the end of the hall, looking south at the indoor garden area. The two rooms will be separated by glass doors, bringing south light into the bedroom. (I kept the north windows quite small.) The loft space above the garden area will be accessible by a ladder. Ted and I dubbed it the "Manatee cave."
Back downstairs, here's a peek into the kitchen. My mom is doing an admirable job ignoring the huge mess everywhere!
Don't worry, I haven't forgotten about you construction geeks out there. Here's the hot water heater (hooked up to a solar collector), in the utility room near the back door:
And behold the mighty HRV ductopus in the utility loft upstairs:
Finally, a photo of the elusive Andrea (me!) in front of my treasured 1938 Deagan Imperial marimba, out of storage at last:
Due to a last-minute change in roof pitch (my fault), we wound up with a structural beam at perfect head-bopping height at the top of our garage stairs. But today it was fixed!
Eric (6'-3") and Eli (5'-7") plan out the surgery:
Don't worry — we didn't carve out an LVL without checking first with a structural engineer. Eli consulted with engineer Ben onsite several months ago, shortly after the garage was built. Ben had a good laugh at our error and told Eli where he could safely cut.
"What's the problem here? This header height seems fine!"
(At 5'-6", I wouldn't have had a problem either. But I would not have enjoyed seeing Ted bump his head several times a day.)
When Ted and I started this endeavor in 2009, I didn't know the slightest thing about construction. I couldn't have told you how a stud wall is built, or even described with confidence what a 2x4 looks like.
My how things change! Just last night I dreamt I was quizzing a contractor about air barriers and external insulation, while harboring deep suspicions that he hadn't properly managed the vapor barrier on the 2x6 walls of the house he was rehabbing. I was gearing up to explain why polyisosyanurate was a better choice than extruded polystyrene (XPS) for above-grade rigid insulation, since the blowing agent used to produce XPS has a much higher GWP (global warming potential) than the one used for polyiso... but then I woke up.
I honestly never intended to jump into the deep end of residential construction theory! We simply wanted to build a comfortable and energy-efficient house, which led us to Passivhaus, which led us to our energy guru Marc Rosenbaum, who opened my eyes to the rough and tumble world of building science.
I have a problem with the Passivhaus people, because they are building ugly freaking boxes. The only way to get a building to last a long time is if the building is maintained, and people have to want to take care of it. People do not take care of ugly things.
Ouch! That one hurt a bit, probably because I sometimes worry that our house is an example. The exterior is nowhere near as bad as some passive houses I've seen pictures of, but it is not quite as handsome as I would have liked:
I should mention that this is the house's least flattering angle, and it looks particularly odd without the solar collector that will attach to those two white strips on the facade (probably making the house look even odder). I'll post more flattering and accurate photos below, but you can see that we have indeed built a big freaking box.
The house didn't start out like this. We got invaluable advice from our friend Camilo, an architect in New York, and he designed something a lot more stylish:
But reality intervened, and we had to stray far from his plan. Our building site is both sloped and ledgy (i.e. lined with bedrock), so a stem-wall foundation was impractical, and we needed to shorten the house from 58' to 46' to keep the lower piers from rising ludicrously high. This meant lopping off some space (which we probably won't miss at all), and it made it easier for us to reach Passivhaus numbers, but it also made the house more boxy and less "architectural."
We were very sad to have to reverse the roofline, since it drastically reduced the amount of space for solar electric panels. We therefore added the overhang to the top of the south wall, which turned Camilo's dramatic design into a stark-looking quasi-saltbox.
That said, I don't think our house is ugly enough to invite future neglect. In real life, it looks a good deal better than that first photo would suggest. You can't really see the garage in that photo, and the garage's south-facing roofline complements the house nicely:
It looks even better from the road (which of course is how most people will see it):
And the best part, frankly, is the interior. While we mercilessly chucked most of Camilo's exterior design, we consulted him regularly about the floor plan and followed his advice even when it would have been cheaper or easier to ignore it. We refused to replace his vaulted ceiling with a standard attic, which meant we had to find joists that were deep enough for Passivhaus insulation and also strong enough to bridge a 26' clear span. We also sacrificed upstairs floor space to preserve an atrium-like expanse above the dining area. I spent countless hours in SketchUp tweaking and tuning the interior, and now that the house is drywalled I can see that my time was not entirely wasted. It really is a cool space, and it doesn't feel generic or boxlike at all.
We all knew this time would come. I've shared way too many details of our construction process, so it can't come as a surprise that I'm going to tell you this one as well. So sit down, relax, and read all about how we chose a toilet.
First some background: Ted grew up about 15 miles from Brattleboro and I'm from the Chicago suburbs, so we both consider northern climates the norm. But we spent much of the last decade in Arizona, which radically skewed our definition of normal. In Arizona it can go months without raining—the so-called rivers are just sandy washes that occasionally flow with water after a heavy storm. Summer enters full swing by the end of April (daily high temps in the 90s, surpassing 100° in May), and it doesn't really cool off until mid-October (highs in the 80s). The hardest part for me was the lack of shade, since desert trees have very tiny leaves and don't grow especially tall.
This developer clearly had a sense of irony
But in 2010 we moved to Vermont, and after six years in Tucson (plus a year and a half in rural Cochise County) we felt as if we'd returned to Earth after living on a poorly-terraformed planet. Seasons! Tall shady trees! Plants that don't puncture you! Rivers with actual water!
It therefore seemed unnecessary to keep worrying about water conservation. Indeed, we had a dramatic excess of water last summer, and installing low-flow toilets seemed like a low priority. But my friend's recent blog post about toilets made me realize I wasn't actually off the hook, so I turned once again to the folks at BuildingGreen for some advice.
They told me that water conservation is, in fact, quite important hereabouts. Wet regions like New England are uniquely vulnerable to drought simply because we have so much to lose. Reduced rainfall could seriously change the ecosystem here, harming numerous existing plant and animal species. After a dry month or two, spring-fed wells can dry up, sometimes forcing homeowners to drill deeper at great expense. So we mustn't get complacent about water use, even though it's rained nearly every day for the last few weeks (not that I am bitter).
Ted and I therefore reevaluated which toilet to install in the house. Last fall we had followed our plumber's advice and selected the American Standard Cadet 3, which uses either 1.6 or 1.28 gallons per flush (I honestly can't remember which version I chose). But I hate the idea of flushing away 1.6 gallons of pristine water every time we urinate, and Ted's sense of smell prevents us from being an "If it's yellow let it mellow" household.
I thought our best alternative would be a dual-flush toilet, but Peter Yost recommended the Niagara Stealth, which he installed in his house more than a year ago. The Stealth ($300) is a single-flush, vacuum-assisted toilet that uses a mere 0.8 gallons per flush (most dual-flush toilets use that amount for only the small flush, and more for the big flush). It's very quiet (Peter let us test his) and by all accounts works great. We even asked a disinterested plumbing supply rep about it, and he told us that a customer with multiple rental properties is gradually buying them for all his units because it's saving him so much on water, and the tenants haven't had any complaints.
I obviously won't be able to fully endorse the toilet until we've been using it for a while, so if you're interested please remind me to post an update next year. And let us all hope that my tendency to overshare does not make you wish you'd never asked.
Ted and I were all set to install LED strip lights, as described in my recent post about choosing LED lights. But then we spoke with my father's friend John—a major techie at a major technical manufacturing company—and he suggested we wait a bit longer.
He said that for the next two years or so, the best LED products will be Edison-style replacement bulbs that use remote-phosphor technology. LEDs do not produce a wide spectrum of light on their own, but when LED light strikes a phosphor, the phosphor emits a wider range of colors. You can see this in the Philips LED replacement lamps: the unlit bulbs look yellow, but the light that comes off them is a nice warm white.
Those kind of replacement lamps are the best short-term approach, but the longer-term approach will be multi-string ("but not RGB"). He said, "They will be phosphor-shifted blue LEDs picking up green-yellow (called BSY), with some combination of red/orange/amber LEDs at the longer wavelengths."
He added, "CRI is only a start at analyzing the problem. It's very outmoded, made a lot more sense in 1950 than today. Doesn't measure reds well (which are very important to human perception), and the spectral absorption are too broad-band." This confirmed our experience of CRI — the lights we were going to buy had a good CRI (85) but was noticeably weak in the red part of the spectrum. Ted looked OK under our test lights, since he has fairly rosy cheeks to begin with, but they made me look a bit more wan than usual.
Our informant likes two lighting models right now:
CREE LR6 (BSY/orange two string) — "This dims well, but the color changes a lot"
One thing he likes about these models is that neither has 120Hz ripple, admitting that not everyone is sensitive to this, but that it drives him nuts. He also notes that efficacy is approaching 100 lumens per watt, "which is a good benchmark for a warm white bulb."
He suggested we wait at least a year before installing LED strip lights for the following reasons (direct quotes):
The models that you're looking at don't actually use DC, but rectified high frequency AC that tracks the input line (120Hz modulated 25kHz). This means a lot of flicker.
They are also are "local phosphor single string", which means bad color.
The efficacy with transformer is probably about 50 lumens/W, not awful, but not good either.
Our new plan is therefore to postpone installing the strip lighting, but to leave all the rough wiring in place. We'll make do with floor and table lamps for a year or so and then install strip lights once they've improved the color rendering and efficacy.
I told him that most of the light fixtures we're buying take regular A19 lamps (Edison standard), but a few will take B10 lamps (Edison candelabra bulbs). He warned that it's harder to make good replacement lamps for smaller bulbs because there's not enough mechanical volume to make a good LED ballast. I asked whether CFLs at that size are any good, and he said, "Most of the fluorescent at that size are CCFLs, which have good life, but won't dim well, and have lower efficacy than larger CFLs. There's a effect called cathode drop which fundamentally decreases the efficacy of these small lamps."
He concluded, "Maybe this gives you something to think about. A lot is going to change in the next few years."
My employer BuildingGreen recently celebrated the overlap of National Poetry Month and National Architecture Week with a sustainable design haiku contest. I am not normally someone who writes poetry, but I quickly discovered that writing haiku was a great way to blow off years of accumulated steam from trying to build a Passive House. So I dropped everything and immediately started tweeting a string of cathartic haikus.
Many of my little poems require some basic knowledge of green building, so I am turning this into a teaching opportunity by annotating my wee œuvre below. Let the learning begin!
Heat recovery ventilation
A punch in the nose
To the next one who tells me
"A house has to breathe."
Whenever I tell people we're building an extremely tight house, someone always pipes up, "Well, a house has to breathe." Yes, and that's why we're installing a ducted heat recovery ventilator (HRV). An HRV is a a fresh-air system with pipes to the outside, and it has a heat exchanger that transfers most of the heat between the two streams.
Our HRV is 84% efficient, which means that in cold weather it will transfer 84% of the heat from the outgoing stale airstream into the incoming fresh airstream. Compare this to a leaky house, which gets fresh air and expels stale air through holes in the building envelope, losing oodles of heat in the process.
Lately when people tell me a house has to breathe, I tell them that a human also has to breathe but we do it with lungs and a respiratory system rather than by punching holes all over our body. For some reason, this metaphor really makes an impression.
Wood certification wars
It's hard to believe, but there is still a lot of unsustainable logging going on these days. Siding and decking are particularly bad, since it often comes from old-growth cedar and hemlock forests in British Columbia. It is therefore important to look for sustainably-forested wood, and the two main certification groups are FSC (Forest Stewardship Council) and SFI (Sustainable Forestry Initiative). FSC was created by environmental groups whereas SFI was originally backed by the wood products industry, and even though SFI has distanced itself from the logging industry, critics still say it is less rigorous than FSC.
Things get ugly between FSC and SFI when LEED gets factored in. LEED is the U.S. Green Building Council's rating system for buildings, and they currently give points only for FSC wood, not SFI. SFI representatives grumble that this is hurting the domestic lumber industry, but... well, if you're really interested you can read all about the "Wood Wars" at BuildingGreen.
You will now understand my next haiku:
Can't decide between
FSC and SFI?
Just build out of rocks.
Thermal bridges are a major avenue for heat loss in a building envelope. They occur when material crosses through the building envelope, creating a direct link between the heated interior and the cold outdoors and allowing heat to escape the building envelope. A classic thermal bridge is the shared concrete slab underneath a house and its attached patio; heat from inside the house travels outside through the concrete slab, and the furnace has to work harder to replace all the lost heat. You're basically paying to heat the outdoors. The reverse happens during the summer, when outdoor heat travels through the concrete into the air-conditioned house.
Squinting and roasting
As the western light shines in.
But look at the view!
The point here is that west-facing windows become a problem during the summer as the sun begins to set, filling the room with unwanted heat and glare. Sadly, most builders ignore passive solar principles when siting a house, instead placing windows toward the best view.
An age-old question
Of all the haikus I posted on Twitter, this one got the most retweets:
No one ever asked
When they built the Taj Mahal
"What about payback?"
Questions about payback are a common gripe among green builders. I ranted about it last year, but I'd like to add that conventional construction is often cheaper than green building because the costs have been externalized. For example, when we rely too much on carbon-heavy energy, we're shoving the costs onto the people who will be hit hardest by climate change. Or when we use materials with a toxic manufacturing process, we are saddling those workers and communities with the long-term cost.
Ted and I have not always made perfect decisions while building this house, but we sincerely tried to bear most of the cost burden ourselves. It made our house more expensive than I would have liked, but my only real regrets are the times when we cheaped out at someone else's expense.
Do you really need
That geothermal heat pump,
Or would caulk suffice?
A lot of people think the best way to improve their home's energy performance is to add fancy equipment like solar panels or a ground-source heat pump. But you can get a lot more bang for the buck simply by improving your thermal envelope. After that, go ahead and install some eco bling. You might not need that ground-source heat pump anymore, but if you install solar panels you'll be able to generate a much higher percentage of the energy you use.
If you want to build a Passive House, you first have to estimate the energy use in a ludicrously detailed spreadsheet called PHPP (Passive House Planning Package). PHPP is incredibly comprehensive and has to be filled out and tweaked by a highly-trained professional. But it lacks at least one key field:
Where do you input
"Milligrams of Valium"
Before installing solar panels, get a home energy audit to find out where you're wasting the most energy. Your house will be more comfortable if you seal leaks and add more insulation, so don't just slap solar panels on the roof without curbing energy use.