Best choice for a siding to disappear beneath vines?
I am designing a home for a narrow lot in Portland, Oregon. Considering the slim side setbacks, three story height and close proximity to large trees, it will be difficult to reach the siding for any maintenance. Furthermore I like the idea of a literal green building, shrouded in greenery including climbing vines.
My intent is to avoid any paint finish that needs renewal every few years, so the siding needs to age gracefully in the absence of maintenance. I’m not particularly concerned that vines will destroy the siding as long as it happens slowly and without damaging the structure. An ideal siding would hold together for a long life cycle even as nature is allowed to take over. Eventually the siding and the vines will both be replaced, but that should be many decades out.
I’ve considered western red cedar shingles as the obvious green solution, but have two concerns. One is exactly how long they would last before falling apart (and there are plenty of examples around town of cedar shingles falling apart). The second concern is susceptibility to fire, especially in a neighborhood of closely spaced homes. People have argued here that even repeatedly replacing cedar is still less consumptive than other siding options, and of course they can be composted with virtually no waste. However the fire issue is troubling.
An alternative would be Hardie shingles, and the individual (not panelized) type does come unprimed. Of course the literature all says painting is required, but once painted I assume that would just necessitate re-painting periodically. If unpainted fibercement shingles could hold together for 50+ years that might be the solution. There are plenty of examples of extremely long-lived bare asbestos shingles, but I’m unsure about the more modern wood pulp based fibercement and it’s hard to find any precedents.
And one variation would be using mineral paint (e.g. Keim) as a one-time treatment for fibercement, which might add to the longevity of the product. Again this seems like it might work but it’s hard to dig up any examples.
This is a light frame structure and masonry or brick veneer are not being considered based on cost and the limited footprint. However, any other suggestions would be welcome.
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Replies
Thomas,
It's too bad that you're not considering brick veneer, because that's your answer.
If your lot is so narrow that maintenance of your siding is difficult or impossible, you don't want ivy. In addition to the obvious problem -- it will accelerate the destruction of your siding -- the ivy may not get enough light.
"Doctors get to bury their mistakes, architects can only advise their clients to plant vines!"
For some reason architect jokes are far less common than lawyer jokes, this is one of the few that I recall. Seriously though I think this is a great idea but you actually have two important selections to make and the choice of plant material is probably going to be far more important in the long term than the choice of siding. As Martin says you don't want ivy, nor any other vine that attaches itself by means of suckers. The suckers do not differentiate between siding, window frames and window glass and you would be setting yourself up for a maintenance nightmare. You need a vine that climbs by wrapping itself around a trellis which you install only in the areas where you want the vine to grow. This in turn suggests a wood siding rather than cement board, to allow for many attachment points needed, though Hardi Panel with wood batten cover strips at the seams would work (you could also introduce additional battens at each stud spacing for decorative effect if you wish). I think your painting concerns should not be a problem if the vine cover works well, though there are a few houses in my neighborhood built about thirty years ago with unpainted P/T pine siding which have weathered quite well, so that might be an option.
I use the term trellis loosely: should probably be a network of stainless steel wire stretched between stainless steel eyes spaced appropriately over the surface of the siding. As to the the choice of climbing plants (not necessarily just vines per se), you will need to consult a knowledgeable horticulturalist in your area. You may need different plant materials on different elevations according to solar exposure. There are some wonderful evergreen clematis varieties that may be suitable for your climate but they prefer some shade I believe. On a sunny wall a climbing rose might be wonderful.
I'm not sure I'd describe WRC as an obvious green choice, either- it's largely old-growth trees and terrible forestry practices in BC producing it.
What about galvanized corrugated metal panels?
James, thanks for your input, and I think you're right that there should be wires to support vines rather than choosing a climbing plant that actually sticks to the building.
Dan, if WRC is not green then what's greener?
David, this is also something I considered and it's a practical solution. However it would look a little garish, not exactly a subtle way to infill a narrow lot. It's hard to embrace shiny metal for that reason, and the house will also be taller than its neighbors. It is possible to imagine a new house being all shiny at first, then eventually enveloped in greenery, and everyone loving it. But if the vines struggled or took ages to spread, it could be a sore point with the neighborhood (and the homeowners).
How about a terracotta siding and chia seeds?
https://www.youtube.com/watch?v=UQW2Z4RblqU
Thomas are you familiar with wood products certified by the Forest Stewardship Council (FSC)?
FSC certification is akin to an organic label for food. There are other 'sustainable forestry certifications' also but in my opinion they are not as rigorous and they were started by large corporations to gain back market share. I just acquired FSC certified WRC lap siding for my house. It was from a certified forest in Northern Idaho. There are several foresters certified in western US and Canada.
To Dan Kolbert's post not all wood is equal. There are different grades of cedar. The highest grade (A or clear) requires taking down larger trees in order to avoid knots. I'm using a D&Btr grade which includes some knots. The lower the grade you can tolerate the more frugal you are being to forest resources.