It is raining hard, and the critic is going round in circles, drifting in a homemade boat. One of the Hayward Gallery's sculpture courts has been flooded. Water overflows and cascades 15 or 20 metres down to the road below. I drift aimlessly through a world of grey - grey clouds, grey sky, grey city. The London Eye turns slowly, Big Ben strikes the hour, a helicopter churns through the wet air. There's a squall coming: I grit my teeth and man the oars.  This voyage round the sculpture court, courtesy of Viennese collective Gelitin, is part of Psycho Buildings: Artists Take On Architecture, opening today at the Hayward. As well as flooding the sculpture court, Gelitin have built a floating dock and provided three or four dubious crafts, nailed, glued and cobbled together from reclaimed timber and junk-shop furniture. The handles of my oars obviously came from the legs of an old chair, and have brass castors on the ends.  Gelitin reawaken the childhood delight of messing about in boats, and make you see the world (and the Hayward, currently celebrating its 40th anniversary) differently. Out on one of the other sculpture courts is a huge, inflatable clear plastic sphere by the German-based Argentinian Tomas Saraceno. Visitors can climb an external staircase and bounce around on top of the squishy membrane, or enter the hollow structure below, through an air-lock, and watch people make fools of themselves up above. Personally, I prefer a death by drowning.  On the third sculpture court, overlooking Waterloo Bridge, the Slovenian artist Tobias Putrih has built one of his fanciful cinemas, in which one can watch films about artists such as Robert Smithson, Gordon Matta-Clark and Gregor Schneider (the latter's buildings are more psycho than anything at the Hayward; he's one of the missing ghosts at the feast).  The idea for this show, and its title, come from a book of photographs by the late Martin Kippenberger, who made fake subway station entrances and a fake forest. Many artists have played with architecture, in all sorts of semi-realistic, bizarre and macabre ways. But the large-scale, space-consuming, immersive environments that artists like Robert Gober, Schneider, Christophe Büchel, Vito Acconci and Kippenberger himself constructed cannot be done any sort of justice in group exhibitions.  Even missing these protagonists, Psycho Buildings is extremely enjoyable - although Brazilian artist Ernesto Neto tests not so much the Hayward's great and gloomy architecture so much as the boredom threshold of his audience. Since the late 1980s, Neto has done pretty much the same thing, filling pouchy sacs of stretchy organza and other translucent textiles with strong smelling spices, creating pendulous, pungent forms. The result is a sort of chill-out zone of swollen glands and dangling testicular bulges. Nor does Berlin artist Michael Beutler's walk-through labyrinth of panels covered in coloured florist's tissue go much beyond the decorative.  Atelier Bow-Wow, a pair of Japanese architects, fare better with their steel-plate Life Tunnel, a crawl space that makes its angular way between the mezzanine and the floor below, with a chimney section that makes a cubistic journey up to the top floor. They've done better elsewhere.  Mike Nelson has remade his To the Memory of HP Lovecraft (1999), previously installed at the Collective Gallery in Edinburgh. This is a wilder, more violent version. I like it a great deal. It is as if some creature from one of Lovecraft's fantasy fictions got trapped in the empty gallery and tried to claw its way out, gouging, chewing and tearing at the walls in a frantic blizzard of splinters and wood chippings. Nelson has also barred the windows and installed a big trapdoor over the stairs - to keep us out or the thing in. In fact, Nelson himself just went mad in there, in a gleeful though exhausting orgy of destruction. The captive being we never see might well be art itself, having a fit of pique in the antiseptic art gallery. It's all very calculated, premeditated and staged.  Haven't we all wanted, at some time, to smash things up, wreck the house, punch the walls and send the furniture flying? In the Frozen Study of a Disaster, by Havana-based Cuban collective Los Carpinteros, an explosive wind has ripped through a fake apartment - perhaps a furniture showroom - sending chunks of wall flying, showering the sofa in shards of glass, and filling the air with dismembered chairs, tables, fridges, beds and electrical goods. It's like a frozen moment in a movie special effect, all kept suspended in mid-flight on lengths of fishing line.  Unlike Nelson's work, the violence here is gleefully cartoonish, and all the more pleasurable for being wreaked on Ikea furniture. The artwork makes the tables, cupboards and doors seem flimsy and papery. As one Carpintero explained to me: "It's like marriage. Everything starts out as a wonderful dream and ends up a fucking nightmare." Another Carpintero turned to him and said: "Hey, but you've never been married, man."  On the top floor, Korean artist Do-Ho Suh has installed a glowing plane of translucent red fabric, a false ceiling that fills a large and otherwise empty gallery. It is a spectacular, ravishing sight, and a great counterpoint to Nelson's scary, messy lair nearby. In the centre of the room, a staircase, made from the same stiffened red fabric, descends from this ceiling without quite reaching the floor. Even the light bulbs, wall switches and banisters have been made from this same red fabric. A disconcerting, life-sized simulation of a place the artist knows well, this is a breathtaking work, as much a reconstruction of a space as it is an image of a memory.  On the mezzanine below is a second work by the artist, a pair of model houses, on a scale of 1:5. One is of the traditional Korean house in Seoul where the artist spent his childhood, the other of a four-storey apartment building in Providence, Rhode Island, where Do-Ho Suh first lived in the US. The houses have mysteriously rammed into one another like battling frigates, in graphic illustration of the collisions and interpenetrations of memory. There is perfectly fabricated debris everywhere. All the paraphernalia in the houses - from furniture to crockery, clothes and books, FedEx boxes on the hall table and scattered dollar bills on the floor - is lifelike in every way. It is engrossing. You could stand and look for hours. One day, the artist wants to build these models at full size.  There are all sorts of affinities between Do-Ho Suh and Rachel Whiteread, who, in her new installation here, also uses doll's houses, which she has been collecting for more than 20 years. Place (Village) 2006-8 is a townscape of mock tudor and generically suburban doll's houses, ranged on shadowy hillsides constructed from travelling crates, and displayed in a space illuminated only by the lights in the houses themselves. The houses are empty, as though abandoned to the night. Mullioned windows stare into the dark. The smallest houses are actually hung on the walls, lending a sense of distance to the tableau.  There is something unexpectedly melancholic and painful about these empty home counties doll's house dwellings, with their vacant, cruelly lit rooms lined in garish wallpapers. It is a suburb repossessed by the dead - the fate, perhaps, of all buildings.  Psycho Buildings is at the Hayward Gallery, London SE1, until August 25. Details: southbankcentre.co.uk
What happens when you let artists loose on a whole gallery - inside and out? Adrian Searle grabs his oars and finds out