TLC's "Trading Spaces," one of television's most primordial home-improvement reality shows, was ending its eight-season run in 2008 at roughly the same moment that American homeowners experienced a disastrous housing bubble-burst, pushing the economy into the Great Recession.

Though it was technically impossible to indict the cable channels, especially HGTV, for their role in the quick-mortgage fantasia, the connections were plain to see: the schedule was (and still is) littered with shows that spur house envy, encouraging viewers to live in a constant state of renovation, makeover and upgrade. Homeownership became the highest expression of citizenship, while decor became the chief signifier of class. "Trading Spaces," which first premiered in 2000, helped ignite that craze, making it safe to waste entire Saturday afternoons watching home-improvement shows. Yet it hardly deserves all (or any) of the blame.

The show has just returned (airing at 8 p.m. Saturdays), essentially unchanged and contagiously giddy, full of its usual surprises and reveals. One is reminded of "Trading Space's" conceptual purity: It never goaded anyone into ditching their old house for an open-floor-plan, granite-countertop McMansion beyond their means. Its core principles were to work with what you have, on a restrained budget. It preached a DIY ethic, asking couples to swap houses and redo a room, aided (some would say strong-armed) by a crafty professional designer and carpenter.

One underlying reason the show was a hit (having been adapted from a British version called "Changing Rooms") was that it took us briefly inside the everyday strangeness of marriage and domesticity, knowing full well that homes — and how they look — are inviolably personal matters.

That same fascination remained when, in its original new episode last week, "Trading Spaces" reopened for business in Simi Valley, California, where two sisters, Michelle and Melissa, live next door to one another — so already it's a little weird. Melissa and her husband, Keith, are redoing the drab, neglected master bedroom belonging to Michelle and her husband, Ryan; Michell and Ryan, meanwhile, will redo Melissa and Keith's guest room.

"Trading Spaces" intends to bring some new talent aboard, but the show knows full well that fans are here to see their old favorites.

In addition to host Paige Davis (still chipper but with a slightly sassier attitude about the gig this time, having been fired and rehired by the show before; "This Ain't My First Rodeo," reads her T-shirt), the designers in this episode are Doug Wilson and Hildi Santo-Tomas, popping into the rooms like much-missed friends. The carpenters are Ty Pennington (probably the "Trading Spaces" alum who flew highest, as host of ABC's "Extreme Makeover: Home Edition") and Carter Oosterhouse. Yes, they've all aged, some more than others, but they also seem genuinely glad to give this another go.

Since "Trading Spaces" came and went, we've been subjected to far worse in the reality/real-estate genre: Shows about million-dollar listings preened over by the smarmiest agents imaginable. Shows about flipping houses that were mostly about greed. Shows about home renovations hosted by holier-than-thou couples with dangerously sentimental notions of design.

"Trading Spaces" returns us to safer, saner space of amateur willingness and neighborly bonhomie.