We fashionable people began to see them differently in, oh, the early 1990s: those postwar, pre-1980s buildings, mostly mid-century modernism - curtain walls, shuttered concrete, all that. We began thinking about the joy of a stressed horizontal, with the steel beams blocked up ever so smartly in plasterboard, or the recurrent pleasure of a bit of 1950s mosaic.
Pioneers and people with a proper grounding in the precepts of modernism knew all along, and were talking about listing the best of that stuff back in the 1980s, when the commercial postmodernist tide of buildings with blue glazing bars and irrelevant pediments was still flowing freely. But in the 1980s, fashionable opinion - and popular opinion, too - would mostly have said demolish the lot. Naturally, not the Smithsons' Economist building in St James's: we know that was posh and special. And not Centre Point, because it was cultish and amusing. But your average curtain-walled office block of 1963, or your Something Gardens Estate of 1959, can't tell 'em apart, all part of a monstrous con perpetrated by a mad monastic brotherhood. Talk about From Bauhaus to Our House; it was all a socking great metaphor for the world we were putting behind us.
By contrast, the new architecture of the 1980s - the new architects, too - had been very user-friendly from the start. It promised fun, with all its talk of eclecticism and visual jokes. And it knew how to talk money, to show off without the slightest embarrassment.
In the central London office market of the 1980s, postwar pre-Thatcher modernist - a "Sixties office block" - was the last thing you wanted. You couldn't give them away. The premiums were attached to "interesting" Victorian and Edwardian commercial buildings - offices and warehouses, wharves and redundant institutions. Nice ceiling heights, interesting detail, good materials that would scrub up nicely. The 1960s stuff simply looked mean - and, by the late 1980s, unworkable because you couldn't get the cabling in. If you wanted full-on Burolandschaft at scale, then buy new from nice Mr Foster. Otherwise get a bit of character.
The same went for residential at every level. Rich people simply weren't building modern houses for themselves then. They were fixing up old ones of various kinds; decorators were more important than architects, by a mile. In the early 1980s I just loved telling my architect friends they'd be unemployed for ever. (Clever, rich, new Labour Gavyn Davies's Baggy House in Devon really shows how the tide has turned.)
All this meant denying a bit of myself, because you can take the boy out of Hampstead but you can't take the Hampstead completely out of the boy. I remember a world where the architects all looked like Hugh Casson (some even looked like Michael Foot!) and wore horizontal-ended, mustard-coloured woollen ties. And all around us were the between-wars refugee modernists' party pieces, and some postwar residential stuff, too. I sat at an Alvar Aalto school table, probably the cheapest thing going then.
The noble aspirations of, say, Congress House, the TUC building of 1957 in Great Russell Street, with its giant pieta by Jacob Epstein in the courtyard, really speaks to me. You just have to close your eyes and concentrate to get the feeling back. Castrol House, on Marylebone Road, that British wannabe rip-off of Skidmore, Owings and Merrill's giant Lever House in New York, said entirely different corporate cool things to my schoolboy self in the 1960s. Completed in 1959, opened by Ernest Marples, Supermac's minister of transport, it was used endlessly in film and TV as a backdrop because there was so little glamorous new office building around. (The owners actually wanted to demolish it in the 1990s. Under threat of listing, they converted it into a block of flats, full of flight capital from God knows where. They also revised the glazing to the slab, with dinky little Edwardianate quarter-lights. Hardly worth bothering.)
But now modern classics couldn't be more mainstream. Just think of the roll-call of designer brands you can conjure with, all those chairs being produced everywhere - from Aalto to Verner Panton. Just think of those post-war furniture sales at Christie's. Just think of all those 1990s high street restaurants. And just look at Elain Harwood's dense, heavy, 750-page book England: a guide to postwar listed buildings. And there it all is, starting with the Wythenshawe bus garage, with its astonishing reinforced-concrete shell roof structure - its spectacular spans, its artistic engineering. We will look twice now. There are these cruel concrete council blocks - Erno Goldfinger's Trellick Tower is now deeply fashionable with Notting Hill trustafarians - and those occasional 1950s private houses built for the dissident rich in the American "contemporary" style, combining rough-stone walls with picture windows and Formica. They look utterly gorgeous to a modern eye. And many of them are still fitted out with all the originals of the "classics" you can buy from the SCP concession at Selfridges. This useful little book, the register of legitimacy, brings it all back. But it brings it back as fashion to a very different world. The mindset that conceived Congress House, the pieties you can see in every stone of those new chapels of the 1960s (the second great boom of church-building, apparently) are completely gone. In their place is an utterly consumerist view of the currency of styles: everyone an art director. And that means that in 2003 all this modern classic thing - it's been going for more than ten years now, you know - is starting to look just that bit middlebrow. Time to move on.
England: a guide to postwar listed buildings by Elain Harwood is published by Batsford (£24.99)
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