I've been thinking about what our options are if the school likes the idea of enclosing the roof in some sort of enclosure
i) permanent or retractable? for now I think we should assume the latter as not only is this more onerous for us but is much more likely to get the ok from the school. also, the idea of a retractable enclosure fits much better with our aim of finding supplementary, not alternative, uses for the roof (we don't want to replace one space with another, but to add to it).
ii) how retractable? should the whole structure be movable (difficult) or should we looking at having a permanent skeleton with a retractable cover (see frank's cafe in previous blog)? again, I think the latter (primarily for reasons of feasibility and likelihood of approval, but also because I like the idea of the skeleton defining/delineating the volume even when the roof is fully uncovered.
iii) materials. wood would be a good place to start w.r.t. the skeleton for obvious reasons (sustainability, the idea of a roof garden/allotment, public acceptability, etc.) but this doesn't mean that we should be blind to other options, particularly if we could source some good stuff from the recycling people Niall spoke to... for the fabric, I would be very interested in using scaffold wrap (the white plasticy stuff they put around building sites, see berner's street hotel)
there's a building on trafalgar square that's currently being refurbished with the top two storeys clad in this material and it gives the building a kind of milky, ethereal appearance and feeling of weightlessness (esp. at night when it's lit up from inside and glows softly). actually, it's not unlike the new effect that SANAA did in new york (below) or that OMA were going for with the Rothschild's building. people generally consider building sites to be eyesores, but to my mind they often provide a lot of interest and dynamism to the urban environment (certainly skyscrapers often look better before the glass is added) and it'd be great if we could convey this.
iv) form. difficult to talk about this without the aid of sketches but I don't have a scanner at home so will just have to add these later. am currently in two minds on this one:
a. curved edgeless bubble (perhaps even a blown up polytunnel considering our aim of creating a rooftop allotment - this links in quite well with the idea of using scaffold wrap), making a clear contrast to the building below while at the same time being quite soft and unobtrusive. the trouble with this option is that it wouldn't really work in this way when the canopy is retracted - it is essentially dependent of the fabric. shigeru ban is a good point of reference for this kind of thing ( = joseph paxton + polytunnel):
b. to go for a sharp rectilinear skeleton, keeping the structure and the canopy/wrap very distinct.
as I said, this doesn't really work without sketches, so I'll have to come back to this. I suggest that this is something that we should all look at together
