Category Archives: finishing

Finishing the bookshelves

We’ve been away visiting family in Japan. Before we left, there was one final thing to do to finish the bookshelves, which was to find and install a nice cherry top for the cabinets. Jeremy Balint, one of great local carpenters, just completed the job. The cherry is still quite pale, but we’re going to use an oil and resin finish and it will darken and deepen significantly over time…

If anyone’s interested in the furniture that’s partly visible in the final two pictures, you’re in luck because we’ll be putting up a post about furniture very soon!

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The Japanese Room

Since the house was declared complete, there has been one room that has remained unfinished. It’s pretty visible too, right at the top of the stairs, there has just been a pile of boxes and wood on the subfloor. We’ve just been telling visitors, “and that will be the Japanese room.”

Now, finally, it is the Japanese room!

After the excellent bookshelves downstairs done by Jeremy Balint, this time it’s the work of another brilliant local carpenter, Joe Calnan. Joe is multi-talented as you can see from the projects on his website: historian, educator, guide, boatbuilder, historic building restorer – and just occasionally, lucky people get to have him do some interior woodwork. We had him in mind for this project from the beginning as he’s also interested in Japanese joinery, and we’re delighted he was able to find the time to fit us in.

What we are calling the Japanese room is a typical multipurpose space that would be found in a small house or apartment in Japan, known as a washitsu. Japanese rooms are generally measured by floor area, in tatami. Tatami are thick mats woven from a special grass straw and filled with another kind of grass stuffing (although many these days have some kind of artifical foam instead), often edged with fabric. The sizing is slightly complicated by the fact that tatami are traditionally slightly different sizes in different parts of Japan, but generally they are around 90cm x 45cm and arranged in various different patterns depending on the exact shape of the room.

We had designed in this space along these dimensions from the beginning, to be a 4.5 tatami space (yojohan), plus tokonoma (alcove) and chigaidana (cupboards). In most traditional rooms, the tokonoma and chigaidana are next to each other, split by a tokobashira, a pillar that is often deliberately rustic, and sometimes even just a whole tree branch. However, in some the alcove and cupboards are arranged vertically, and this is what we decided to do because it makes the cupboards, in which we will store guest futon mattresses, more easily usable, and it also makes more a potential feature of the top of the low cupboards. We will still have a tokobashira in the centre but the ash branch from the island we are going to use is still still drying. The tokonoma has certain other traditional features too, usually a flower arrangement and scroll, both of which are changed seasonally or more frequently. Ours also has an otoshigake, a valence at the top of the alcove. The room is not divided from the upstairs hallway by walls and a door but by shoji, translucent sliding screens (although it could also be fusuma, which are opaque screens).

Our tatami mats and shoji screens both came from the Vancouver-based Lilin, who were really excellent to deal with and very reasonably priced for quality products. The shoji are made of fir, and this really determined the choice of the rest of the materials in the room – and outside. We had already choicen to use a fir top for the stair rail, and Joe used fir for the frame post and kamoi (top rail) for the shoji, and carefully matched pieces of fir for the valence and the cupboards. The tatami mats are held in place by a narrow fir frame and the base of the sliding screens and cupboards. However, the shikii (base rail) for the shoji is clear maple, the same as the floor of the upstairs landing. Maple is also much harder than fir, which makes it more suitable for the shikii, which will need to be hard-wearing. We’ve generally tried not to use any foreign or unsustainably-harvested wood for any part of the house, but Joe had a large piece of Honduras mahogany, which he has had in the store in the back of his workshop for quite a few years, which was absolutely beautiful and was almost exactly the right size for the cupboard top. All Honduras mahogany is now supposed to be sustainably harvested or cultivated, and this was certainly not from Brazil, where that is often not the case and mahogany is frequently illegally harvested.

The tokonoma is lined in this really special hand-made silk wallpaper from Ubushina in Japan, which has ‘grain’. Inspired by pictures on their website, we decided to hang it as equal size squares, alternating the direction of the grain for each so that the light would catch it in different ways. It made the cutting and hanging processes a little more complicated but the result is beautiful.

And finally, we sorted out the lighting. The tokonoma is lit by a flexible LED strip around the inside of the valence. This can be set to all kinds of color outputs, and even has some sort of ‘disco’ settings, which FK loves, but generally, a warm yellow light works best with the wallpaper and wood. The main room light is another one from Toshiyuki Tani, who also made the birch-bark shade in the lounge. It’s a simple washi-paper shade in the shape of Mt Fuji.

Overall, we are delighted with the room.

Reflections After a Year of Living in Our Passive House

Although there is always more to do, at the end of 2017 and after a year of living in our passive house, it’s a good time to reflect on the whole process.

This place was both the product of a shared dream between Kayo and I to create a sustainable and comfortable family house and an experiment for all of those involved. Sitting here on a late December morning after a night when the temperate dropped to an unusually cold -24ºC (yes, and that’s without wind-chill) outside and looking out on the sign shining on half a metre of snow, while feeling totally comfortable inside at 21ºC, we think we’ve achieved our dream and the experiment has been a success! We would even stand by the revised cost estimates we produced back in December 2015.

Wolfe Island Passive House in winter

There are some remaining problems. The first is a building envelope tightness issue that is due to a manufacturing fault. The Optiwin Motura sliding door, which was a prototype, has never sealed as tightly as it should, and last winter and this, we’ve resorted to sealing it up with gasketing and tape to maintain the building envelope. However, this is fixable: Optiwin have been as thorough and responsible as ever, and both issued us with a partial refund for the door and got back to is with a very detailed analysis of the fault and how to remedy it, which we will be putting into place in the spring. I don’t think anyone else considering using Optiwin needs to worry about this – as I said, our door was an early version and the current models are already better.

The second issue was noticed by Malcolm Isaacs, our passive house consultant, in checking the report conducted by Anthony Mach. He reckoned that the passive solar heat gain in winter is not as good as it was in the calculations we made. In other words, the house is not as warm as it could be. It’s not actually something we find uncomfortable, it’s more an optimum performance issue. The reason, we think, is that the downstairs porch roof overhang is not quite the exact height / angle / extension as in the original designs. However this means that to remedy the (small) differences, we’d have to almost completely rebuild the porch. There were at least two points at which things were changed in the design process that could have affected this, and as we were working not only with an architect and builder but also a passive house design consultant and engineer, and a manufacturer (for the pre-fabricated CLT structure), there were even more communication issues to manage than in a normal build. These communication issues can be crucial and really, all calculations need to be checked and recalculated every time there is a change. And of course, when you are working with any kind of pre-fab, there is a point after manufacturing has started that you can’t change anything about that any more and any changes from that point onwards have to be adaptations to what you’ve had manufactured.

Related to the issue of the passive solar heat gain – had we known this was going to be the case, then we probably would have had underfloor heating installed. In fact, we probably should have done anyway as a kind of reserve. Had we done this, we probably wouldn’t have needed the little Thermolec air heating system we have as part of the ventilation. We were just assured that it would be so warm anyway that underfloor heating wouldn’t make any difference. That’s not really true in practice but it’s warm enough so we aren’t complaining! Again, at this point it would mean substantial rebuilding (ripping up and relaying our lovely wooden floors) to do this. The lesson is: lay the underfloor heating even if you end up not using it. It’s better to have the possibility than not.

The other remaining problems are small design issues, that people thinking about building a passive house, or even just any house should note. The first is that although we really like our open-plan downstairs space, and visitors love it, however Kayo would now want a more specific dedicated work area or room. What we did design in was inadequate. It’s difficult to see how we could have done this just by tweaking the design we have. So, it we were starting again, we would include this as one of the essential elements and design around it, as we did with the kitchen.

The second minor element does relate more to passive house design, and it is the way the entrance works. We have an amazing Austrian-manufactured passive-house-certified front door from Tarredo. The only problem is that you still have to open it and once you open it, it doesn’t matter how insulated the door is. Of course, no-one leaves the door open very long in winter in any house but any heat loss is a problem in a passive house in very cold climates. Back when we were still thinking about rebuilding our old house, we had designed what we refered to as an ‘air-lock’ (like in space-ships), which was essentially an insulated porch outside the building shell, which had two insulated doors to outside and inside. Somehow, that element got lost when we moved to designing an entirely new house. I’d really recommend to anyone building a passive house in a cold climate to think about this because, especially around the Holiday season when you have people coming and going, the front door gets opened a lot more than you’d like from a passive house point-of-view! The plus side is that the more parties you have, the more all those people in your house also heat it up substantially. However, whichever way you are thinking about it, you have to factor people and behaviour into your design. The good news is that this particular problem is easily resolved. We think what we will do is create a closed-in porch space outside the front door. We’ve got room. The only question is whether we make it permanent or seasonal and removable.

There is really nothing that has happened in this year of living in our new passive house that has made us regret or rethink the building process or the big decisions we made in the design.

The Zehnder ERV is a minor miracle. The air quality in the house is so good that it almost makes us forget the mould-infested air we used to put up with as normal in practically every other house we’ve ever lived in. It just keeps working in the background with minimal need to maintanance (occasional cleaning or replacement of filters).

We still totally recommend using Cross-Laminated Timber for the structure, however we don’t think it’s necessary to use it for all interior walls, and combining CLT for the main structural walls, with more standard stick-frame and drywall for the other interior walls would make for a more flexible design that would allow you to do things like changing your mind on where electrical sockets etc. go – and even where the walls themselves go.

However, we know that Canadian manufacturers, at least in the East, are still not capable of doing the precise factory-cutting that we had done. Someone needs to make the necessary investment to do so, because CLT should be a standard material in home-building here considering Canada’s timber resources and need to well-insulated homes in a world where we are at the end of the era of limitless oil and gas for heating. Were anyone to use Canadian CLT, however, you wouldn’t be limited, as we were, by the dimensions of shipping containers. You could be more flexible with your design. A lot of things in our design started from this, which meant we went down a certain route.

We would still have the same advice for those considering using CLT as we had in this post back when it seemed that disaster was afflicting our build in January 2016: DON’T start building in the Fall in a climate like this, DO wrap your CLT structure in a breathable, water-proof house-wrap as soon as it’s up.

The roof might also be something I would rethink were we starting again. We designed it to fulfil several functions: to be at a good angle for generating solar power in the shoulder seasons and winter, to provide shade for the upper storey windows in summer and of course to be able to contain enough insulation. Originally, we were not going to use CLT for the roof, but the horror stories we heard about thee practices of truss manufacturers around here convinced us to give it a go. With CLT roof panels, we got added structural strength, which will mean the weight of any number of solar panels is no problem, however we had to have a floating rafter design (and here) in order to retain the overhang. This looks beautiful but it was very complicated to engineer and caused the insulation installation to be much more difficult – and cutting the wood fibre insulation we used into exactly-sized triangular sections was not easy (especially in the depths of winter). Had we started with CLT as our primary material, we might have made different decisions here: we could have gone for entirely different roof designs, and gone for ground-based solar panels, and considered other ways of shading. However, just aesthetically, I really like our roof and I like the fact that it goes against the grain of having roofs finish flush to the walls.

In the end, we have a beautiful, sustainable high-performance passive house, which we love and which works. It was a long journey getting here but it was worth it. We will keep occasionally updating this blog with things that we are doing (we’ve still got a solar PV system to install in 2018 for a start) and performance updates, but in general there probably won’t be more than a post a month in 2018. And we’re always very happy to be contacted with questions from other people considering building sustainably.