Wood construction is all the rage these days, and for good reason; wood is renewable and it stores carbon. New technologies like Cross-Laminated Timber (CLT) have busted the traditional limits on height. Now architects and engineers are pushing that height limit; Berg | C.F. Møller Architects and Dinell Johansson have proposed a 34 storey tower for Stockholm, their entry in a limited competition for an "ultra-modern residential high-rise building."
The architects describe the virtues of wood construction (with a little bit of exaggeration) :
Wood is one of nature's most innovative building materials: the production has no waste products and it binds CO2. Wood has low weight, but is a very strong load-bearing structure compared to its lightness. Wood is also more fire resistant than both steel and concrete. This is due to 15% of wood mass being water, which will evaporate before the wood actually burns. In addition, logs get charred which protects the core. Wood secures a good indoor climate, perfect acoustics, helps regulating the inside temperature and can be exposed without being covered with plaster or other costly materials.
That is perhaps pushing the envelope a bit; while wood structures are engineered to char in a fire, which protects the wood while leaving enough for structural strength, it might be a stretch to say is is more fire resistant than concrete. But it is certainly not as flammable as the concrete people keep saying. (See them dancing in the streets after this fire in British Columbia)
In Berg | C.F. Møller's wooden skyscraper, the pillars and beams are made of solid wood. Inside the apartments, all the walls, ceilings and window frames are made of wood as well and will be visible from the exterior through the large windows.
It does look warm and comfortable, more like a cottage than an apartment. I do wish there were some sprinkler heads showing though.
The plan is fascinating. There is no internal corridor that wastes a lot of space; just a little elevator lobby. The fire exits are reached by using the balcony that runs around the building. When I was a builder in Toronto a while back, I tried this at 20 Niagara Street; It made for wonderful spaces with windows front and back, but it was murder getting approved with a building code that didn't anticipate elevator lobbies without access to stairs.
Other green features:
Social and environmental sustainability is integrated into the project. Each apartment will have an energy-saving, glass-covered veranda, while the building itself will be powered by solar panels on the roof. At street level there is a café and childcare facility. In a new community centre, local people will be able to enjoy the benefits of a market square, fitness centre and bicycle storage room. A communal winter garden will provide residents with an opportunity to have allotment gardens.
More at Berg | C.F. Møller Architects