In around 1900 most Amsterdammers had their weekly wash in a tub in the kitchen. The water was heated on a paraffin stove. In 1891 the city opened two bathhouses for school children who went there with their class. After 1911 the city started becoming actively concerned with the 'hygiene'of all Amsterdammers. Public baths were built in the new neighbourhoods and the historical centre. By no means all citizens were persuaded of the need for personal hygiene, so extensive propaganda was brought to bear. The building regulations of 1933 required a bathroom in all new developments; even so, in 1951 only a quarter of the homes had a bathroom. After the 1970s the municipal bathhouses lost their function. Only the one on the Da Costakade - the last to be built - is still open. The rest, often buildings of unique architectural interest, were pulled down or converted into theatres, cafés, islamitic baths, Hindu temples, rehearsel rooms or breweries.