Steamy Architecture

In Finland this week, architects and designers are exhibiting new kinds of saunas, including one seaside villa with four different saunas. At what point, one might wonder, does a structure cease to be a house with a sauna and start being a sauna with a kitchen and bedrooms? Hopefully, one might respond, as soon as possible, especially if the sauna looks like this or has a sink made of birch plywood.