This 2,200-square-foot house in southern Vermont stays comfortable all winter using less power than a hairdryer.
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Snowy house

Today I made Ted sniff a stranger's floor

Submitted by Andrea on October 1, 2011

Ted and I visited several houses today in the NESEA Green Buildings Open House Tour. A bunch of homeowners in the northeast kindly opened their doors to nosy strangers and showed off their eco-upgrades.

Many of the houses had solar electric or hot water systems, and others had superinsulation, high-efficiency heating systems, green building materials, etc. All the houses we saw were optimized for passive-solar performance. We enjoyed meeting other nutjobs green building enthusiasts, and when we paused to shut up about our own project we learned quite a lot of useful stuff.

One house was a brand-new net-zero house, which the owners moved into only last week. In addition to many energy-use upgrades, they used LEED-friendly materials such as PaperStone counters and Marmoleum floors. I was particularly interested in the floors, because Ted and I haven't yet decided what to install in the rooms where hardwood floors would be impractical. I'd been considering linoleum (which is what Marmoleum is), but it was a non-starter because of Ted's sense of smell.

Whenever I mention "Ted's sense of smell," you should imagine that the words are followed by a thunderclap or a horse whinnying. For me it's an ominous, implacable force that must be appeased. I have a fairly strong sense of smell myself, but Ted's is bizarrely strong and offended by things I can't even detect. Many times have we walked into a hotel room that seemed just fine to me but was promptly declared "reekitudinous" by the sensitive Ted. We have definitely pushed more than one hotel clerk to the limit of their "customer is always right" patience.

When I suggested linoleum floors in the kitchen or laundry room several months ago, Ted's sense of smell (speaking through Ted) nixed it, citing some stinky floors in the house where he grew up. I was under the impression that Marmoleum and its ilk are actually quite benign, but Ted wasn't interested.

So when we toured that net-zero house, and the chatelaine pointed out the Marmoleum floors in the laundry room, I ordered asked him to get down and sniff it. And lo, he declared it odorless! I should contact the homeowner and ask if it was the edge-locking Marmoleum Click or the Marmoleum tiles that need to be glued into place. But at least I can put Marmoleum back onto the list of flooring options.

This may not be the last time I make Ted sniff flooring or paint; as we start choosing interior finishes his nose's advisory role will only grow. For the moment I will resist adding it to this website's tag cloud, but I make no promises for the future.

Fun with light fixtures

Submitted by Andrea on September 17, 2011

My quest for attractive and inexpensive light fixtures has begun, and my old friend the Internet is ready to help. I have no intention of turning this website into an interior design blog, but I couldn't resist sharing my bright idea.

I quite like this light fixture, but I wouldn't dream of sullying our Almost Passive House with an egregiously incandescent bulb:

However, I think it would look smashing with a Plumen CFL, don't you think?

Yes, Plumen bulbs are pricey ($30 USD), but the fixture itself isn't too outrageous ($119), so I think this could work. Not sure where to put it, but I'm sure we'll come up with something.

Lighting: My nebulous plan

Submitted by Andrea on September 15, 2011

The time has come, the Walrus said, to start deciding on interior fixtures and finishes. I've been focusing for so long on things like the foundation and the building envelope that it feels weird to focus on mere fripperies, but I can put it off no longer. Admittedly, I picked out my kitchen faucet years ago (I installed the same one in two previous houses), but I'm in a fog when it comes to interior lighting.

Ted had the clever idea to use LED strip lighting to give rooms the ambiance of a dorm room lit by Christmas lights. It's a soft, friendly sort of light, which is all we'll need when we're using our laptops (i.e. 90% of waking hours). Furthermore, we could use RGB controllers to change the light color, which would look pretty darn excellent. And of course we'd have some bright overhead fixtures for times we want to actually see things and not just pass the bong around. (I'm speaking figuratively, not literally — Ted and I are utterly and perhaps boringly substance-free.) LED lighting: Energy-efficient and mighty slick.

Alas, I've found no examples online of what we want to accomplish. I've found a lot of McMansiony-looking LED cove lighting, which is not our style at all. I'm imagining LED strips tucked behind curved moldings but not so close to the ceiling. Ideally it would bathe the wall in weird indirect light and look really cool.

But I have no idea if this would work. I suspect you need something above the LED strips to reflect the light back down. Furthermore, there are heaps of LED vendors online but I've heard there's a lot of junk out there. So today I called a lighting consultant recommended by Eli to see if he can help me navigate this bright glowing sea.

We spoke briefly on the phone and he warned me that LEDs are currently more expensive than conventional lighting (sigh). He confirmed that most of the LEDs available online are crap (and no, he doesn't sell anything himself — he just provides recommendations). We'll probably set up a meeting with him to discuss our wild notions and to see if we're heading in the right direction.

As for the overhead bright lights, I think we'll use a combination of LED recessed lighting and hanging fixtures fitted with GU24 sockets [ETA: Or not — see below.]. That is, if someone doesn't convince me that GU24s are a flash in the pan (ha!) and that this recent article about GU24 lighting from Green Building Advisor is all wet.

I have a sinking feeling that LEDs are not quite ready for prime time, which is frustrating because they surely will be within a few years. And of course they use a mere squeak of power compared to incandescents, and they are less flickery and annoying than CFLs.

Words of lighting wisdom are welcome!

[Added on 2011-09-18:  Erik Haugsjaa emphatically pointed out that GU24s are best suited for landlords or developers who want to force residents to use energy-efficient bulbs and that they're actually a terrible choice for us, given the lack of fixtures available. So we'll go with good old Edison overhead fixtures instead.]

In praise of Vermonters

Submitted by Andrea on August 30, 2011

It's been a very hard couple of days for Vermont. Not so much for Ted and me — our apartment and our building site are both well uphill of any flooding. But it's been painful to see all the damage, both nearby and throughout the region.

I don't know how much rain fell on the building site this past Sunday, but there was hardly a trace of it when we went up the next day. Much of the credit goes to Wayne Corse, owner of Corse Excavating, who graded our site. A small amount of water had pooled in the gravel bed under the house, but nothing of concern, and there was no evidence of run-off into the road. Eli's team was rather impressed by the lack of erosion, and so were we.

But we weren't entirely surprised — we've been delighted with Wayne ever since we met him. He has just the right blend of time-tested know-how and openness to new approaches. We talked to another excavator who mostly wrinkled his forehead and shook his head at our crazy notions. But Wayne has a can-do outlook and a flexible mind that likes to find the right solution to the problem. In fact, I think his attraction to doing things right is what makes him ideal for our crazy project.

He also worked hard to fit into our schedule, even though he's been flat out busy with other jobs since spring. We had talked with him last summer and had him do a little scraping, and apparently this was sufficient to make him feel like he ought to follow through and finish the job even though he was swamped. Eli had heard good things about Wayne but had never worked with him before and was skeptical that Wayne could fit us into his tight schedule, but Wayne kept his word and managed to get work done as we needed it, even if it meant coming out on a Saturday morning and operating the big machines himself.

Which brings me to another Vermonter, Eli Gould. Eli already had a solid schedule when we first called him in late April. But he couldn't resist the lure of a super-efficient house and somehow used a time-turner to design and build our crazy foundation.

Eli is a different model of Vermonter than Wayne. Wayne's family has been in the state for centuries, whereas Eli is the son of back-to-the-landers and grew up on a commune in Guilford (just down the road from the commune where a wee Ted ran around while his parents sang and performed). He went to Yale and had to convince the administration to let him double-major in Forestry and Architecture, a perfectly logical combination hereabouts but a little weird for the Ivy League.

He has been working in construction since he was a teenager, and unlike most elite college grads he skipped the 20-something urban bar scene and got right back to work in VT. The result is that he's not yet 40 but is an established expert in timber-frame construction, has his own saw mill, and employs a crack four-person crew. He and his wife (a 7th-generation Vermonter) have three children and live just up the road from his wife's family's organic farm.

Wayne and Eli are undoubtedly swamped right now. Eli was already driving around helping people with his generator and sump pump on Sunday afternoon as rain was still falling. He sounded a bit frazzled when Ted spoke to him today, presumably because he's been working like mad to help his neighbors, all while keeping our project on schedule (mostly to keep his crew fully employed). And I can hardly imagine how busy Wayne must be now, trying to replace all the structural dirt that's now gumming up the Connecticut River. If Wayne was already flat out before the storm, I suspect he'll be working non-stop until winter rolls around and it's time to start plowing.

And there's a hell of a lot of work to be done. Vermont is in bad shape. Many roads are impassable — for example, a waterway has changed course and is now running through Route 9 (the major east-west road in southern Vermont). Many towns are hard hit, and contrary to what you might think based on the ski resorts and the crazy house we're building, there's not a lot of money here.

Fortunately, there are a lot of people like Wayne and Eli: people with deep ties to the community and an unhesitating desire to take care of the people around them.

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I hasten to add that Vermont's natural beauty and the charm of its towns are entirely intact. The news coverage of Brattleboro, for example, shows a torrent where Whetstone Brook used to be and a waterlogged panorama on Flat Street, but that's only a small part of downtown. The rest is undamaged and humming with activity. So if you're looking at photos online and thinking "So much for Vermont," you are quite mistaken.

The Dryer Conundrum

Submitted by Ted on August 12, 2011

One of the problems with building a tightly sealed house is that a lot of things we take for granted in a regular house suddenly become difficult when your main ventilation system runs at under 100cfm. A dryer typically blows 150-200 cfm when it's running. This means that it's going to be sucking cold air in through the HRV. On a really cold day, this could cause serious trouble for the HRV—the exchange plate could frost over. But more than that, it's (ironically) blowing warm air out of the house, while at the same time sucking cold air into the house. Again, on a cold day, really not what you want.

Range hoods cause similar trouble—they want to push air out of the house at >100cfm, and the air they are pushing out is generally warm air from the conditioned airspace, which must be replaced with cold air from outside. This seems like a minor issue until you consider that, aside from insulation, one of the main reasons that a Passivhaus has such a low energy budget is that you aren't heating large quantities of outside air as it leaks in through your drafty building envelope. So when you turn on these vents, your undersized Passivhaus heating system may be unable to keep up.

An additional complication is that if you have any appliances in the house that burn any sort of fuel, you are going to be creating a relative vacuum outside of the those appliances, and that might draw combustion products into the interior airspace that ought to be going up a chimney. We already had to tearfully let go of my 30,000 BTU wok ring dreams (actually, Andrea was remarkably dry-eyed) because of combustion products that couldn't be readily ventilated. No gas stove either. But externally ventilated gas heaters are very popular in tight homes, because they can be very efficient. Marc had a wood stove in his house in New Hampshire (although that wasn't a Passivhaus). Anything like this is going to be a potential hazard if you have exhaust fans running separately from your HRV.

Fortunately, we already gave up on a gas heater and decided to go with a heat pump instead. So we don't have to worry about that. But lots of exhaust vents are still something we have to avoid.

What a lot of Passivhaus people do is to set up drying rooms in their houses. This isn't a bad idea—it can be as low-tech as an indoor clothesline, or as high-tech as an enclosed space with a dehumidifier and/or a heater, plus some kind of exhaust fan that exhausts into the living space. We don't really want to dedicate a special room to this task, but we could certainly set up drying racks in the utility room and the mudroom on laundry days, and I suspect we will.

However, on a practical level, there will be times when we will want a dryer, either because we are drying more clothes than we have space for, or we are in a hurry, or whatever. Plus, for resale purposes, not having a dryer is kind of a non-starter. So I did a little research, which I thought I would share here.

The cheapest product I could find is an LG condensing dryer. This works the same way a regular electric dryer does: there's a heating element that heats the clothes to drive the moisture out, and a vent. Where it differs is that instead of leading outside, the vent leads into a condenser system which condenses the moisture out of the air, filters out the lint (sort of, according to some reviewers), and dumps it down the drain.

This would certainly work, and work well, but there are two problems with it. First, it turns out that it consumes more energy than a plain old electric dryer. When you count the cost of heating the replacement air, it's probably a wash, but this is definitely not a win. The second problem is that it cools the condenser with cold water from your tap, which it dumps down the drain. I get the impression that it's not a lot of water, but there are still some problems. Some people love this device, and some hate it. The ones who hate it often talk about problems they've had with leakage and pump failures. I suspect that the Rube Goldberg nature of the condenser has something to do with this.

So I did a little more research, with the help of Green Building Advisor. Actually, a lot of what I learned came from reading GBA, and I recommend this article highly if you want to drill a little deeper than the presentation I'm offering here. GBA talked about a Bosch system called Ecologixx that's called a "heat pump dryer."

When I was reading the Amazon product page for the LG dryer, I just assumed that it had a fan and a dehumidifier, which seemed like it ought to be more efficient than a heating element, but GBA cured me of that presumption. However, the Bosch Ecologixx series of dryer products do in fact work pretty much the way I had hoped the LG would. Most of these products don't seem to be available in the U.S., but the Bosch Axxis dryer is available, and it's actually pretty reasonably priced—about $200 more than the LG. Not everybody loves it, but it looks like a win in theory.

The bottom line is that I feel pretty good about not putting in an outside vent for the dryer. I don't love that this means we have to get rid of our Kenmore dryer, which has been a friend to us for many years, but I suspect that Freecycle will help us to find a good home for it.

How the foundation works

Submitted by Ted on August 10, 2011

Andrea promised a while back that I'd explain how the foundation works, but I haven't done that yet. We went through a fairly long and painful process to get to the foundation we have now. I think it was worth it—the current foundation looks very cool, and I think it will function well. So let's take a tour.

From The TopWhat you see to the right is the pier foundation as viewed from the west side, looking east down toward the road. You can just see the roof of the car behind the foundation of the garage. That's the sort of U-shaped bit of concrete to the far right, which I will not be talking about, since it's pretty much just a normal foundation.

The horizontal bar of concrete that's closest to the camera is a grade beam. It's mostly resting on footings that have been pinned to ledge, although there's a point in the center where the ledge comes so high that there's just grade beam on ledge, with no special footing underneath. What you can't see from this angle is that the ledge drops off pretty steeply on the other side of the grade beam.

In the center, you can see a wall heading east from the grade beam. This is a shear wall—it's there to prevent racking in the east-west direction. It's solidly on ledge all the way down. The big dark grey wall that's further down the hill is another shear wall that's to prevent racking in the north-south direction.

Tall PiersRacking is a situation where there is a differential force on a wall that tends to try to bring it out of square. The force is called a shear force. Shear walls are shaped so as to resist the shear force. Shear force in earthquake country comes from the ground moving, while the inertia of the house tends to want it to stay in the same place. So the foundation accelerates in the direction of the shear force, and the top of the wall has to move to catch up to it. If you don't have a good shear wall, the wall can fail.

A house that's on piers has limited shear strength, because the piers are just big sticks poking up out of the ground. The footing might look like it will have some shear strength, and indeed the rebar that connects the footing to the pier, combined with the rebar in the pier, does give it some shear strength. But many homeowners in the San Francisco Marina learned the hard way that a house standing on piers with no shear wall is likely to collapse.

But we don't get earthquakes in Vermont, right? Well, not as often as California, but it's best to be prepared. What we do get, though, is high winds. With winds, the ground wants to stay in place, and house wants to move, which will tend to make the piers fall over. We have a pretty tall wall to the south. So we need enough shear strength to accommodate that wind force without failing. So our structural engineer, Ben, specified these shear walls.

Pinned To LedgeThe other advantage of the shear walls is, I hope, entirely psychological: there are two piers that are not directly pinned to ledge. I worry a little bit that these piers might somehow fail—they might start to wander, or we might have gotten the drainage and cover wrong, and they might move due to ice expansion. I don't think this is a real risk—we examined this issue carefully and concluded that the footings were secure. But if for some reason we blew it, the shear walls give us a huge additional safety factor that will allow us to correct any problem that should arise. Even though this is extremely unlikely, the fact that they are there gives me a lot of peace of mind.

Referring back to the picture at the top again, you can see a slot in the north end of the north-south shear wall, and a notch in the south end. These are to accommodate the laminated veneer lumber (LVL) beams that will be running east-west along the tops of the piers. So let's talk about wood for a minute.

NotchesAnywhere where there is horizontal contact between the foundation and the concrete, we will have pressure-treated lumber. So the grade beam at the top will have a 2x (two-by, not two layers) of PT on top of it. The shear walls will have 2x or 4x, depending. There are notches on the east side of the grade beam on the north and south ends to accommodate the LVL beams; each of these notches will have first a layer of PT, and then the LVL beam will rest on top of that. The LVL beams will be attached to the piers with metal brackets.

Ultimately, when all the foundation wood is in, we will effectively have a sill plate to rest the floor box on. In places, it will look just like a traditional sill plate. In places, the top of the plate will be an LVL beam.

What ties this foundation together is the floor box. The bottom of the floor box is a structural membrane made of zip sheathing nailed to the bottom of the floor joists according to a nailing schedule provided by Ben. This will create a box that is very resistant to deforming as a result of differential forces. This is what allows the shear walls, which are not otherwise connected to the piers, to keep the piers stable.

By the way, I should point out that while it might sound like I know what I'm talking about here, I'm relaying to you a layperson's understanding of how this all works, not a structural engineer's. Hopefully what I'm saying here will be of some benefit in terms of telling an interested reader what sorts of things to look out for, but it's no substitute for actually hiring a structural engineer to analyze your specific project. If you're flying your house the way we are, you definitely want expert help.