Hi all. I am building an adobe, rock and wood round house with a reciprocal roof. What ideas do people have for roofing. Low cost. Environmentally friendly. Living roof would be nice but we have heavy frost in winter and don't want an ugly dead roof half the year.
Paula from South Africa
Wood shakes would be my first suggestion for your region, then perhaps thatching of some form that is indigenous to the location. Next would be a metal shingle roof of some form.
I like…aesthetically…reciprocal roofs, but they can be very challenging for the beginner to apply a leak proof covering over. Shallow pitches are more prone to leaks than steep.
I would ask, what is your vernacular forms of architecture and what do they use?
Location: South Africa
posted 5 years ago
Wood shakes look great. A bit tricky to get hold of here. But looking into it.
vernacular architecture is mudbrick, stone, wattle and daub, reed roofing. But you need a steeper pitch for thatch.
Thanks for the help!
I love the look and the concept of reciprocal roofs as well, but they really look like a pain to make leakproof. The way to have an 'easy' roof, as I understand it from people who have actual experience, is to keep it steep and aggressively minimize seems and protrusions. The 'ideal' roof from this perspective would thus be a reasonably steep gable.
A reciprocal roof is nearly the opposite of that, in most cases. Lots of seams, on a usually lowish pitch, with some complicated bullshit to deal with the center.
Jay, are you aware of any books, sites, posts that discuss dealing with this?
A green roof using a thick flexible membrane that can cope with all those different segments seems by far the easiest option if you want your reciprocal beams to directly support the roof.
Is there any sort of succulent or moss or some such, native or common to your area, which doesn't get too ugly to live with over the winter?
Another possibility to consider: I have seen some reciprocal roof designs using a lower layer of reciprocal beams to support a roof that does not exhibit the reciprocal roof 'stepped' effect. I believe the way they are doing this is by using the reciprocal beams to support a central 'collar' structure at the point where the reciprocal beams overlap. Then, this collar supports an upper layers of rafters which One way to do central collar, that in turn supports an upper layer of beams which span right to the supporting wall at the edge of the building.
I believe the AMAZING Bunraku Puppet Theatre building in Japan uses this technique to have a round roof above the reciprocal structure.
This and some other examples here: www.baubiologie.at/workshop2013/Reciprocal-Frame-Architecture.pdf
I think I have also seen this accomplished with secondary beams running above the reciprocal beams, with suitable standoffs between them, but can't put my finger on an example. This seems a less elegant approach in any case.
Jay C. White Cloud
posted 5 years ago
I too love the aesthetics of "reciprocal roofs." I don't recommend them to novice or DIYers which seem to be the majority of who wants to try and build them. Chris (Chris Hall) is a well known Asian style timber framer and woodworker. Chris and I have been friends and acquainted for quite some time and I would suggest (a subjective view) that Chris probably has one of the best articles on the Internet covering this type of roof framework.
As for books...like the style itself...it is not aimed at the DIYer or beginning Timberwright: