HE urge to renovate one, two or three beds — even a bunkhouse full — can strike anytime. Maybe it's the strained look of your country weekend houseguests, bent over and hobbling on the way in to breakfast. Or maybe you, the on-site host, have simply had it with your own bed of stones. One solution is to simply chuck out the old and start over, armed with an unlimited charge card and the patience of a mattress-shopping saint.

Alternatively, there is the bed makeover, retro-fitting existing sleeping surfaces with healing elements like air, foam, cozy warming blankets and sheets with off-the-wall high thread counts. By carefully upgrading, you could end up with beds so swell they qualify for haute hotel status.

A variety of bed remedies were sleep-tested over a period of weeks on a 20-year-old king-size Sterns & Foster mattress, which looked perfectly fine to the naked eye. But two decades of nightly use had cost the Regal 111 Superior two inches of its once lofty height, compacting it into a dense platform that lacked even a suggestion of its original subtle give and confident support.

Now though, the tired mattress has become an incredible sleeping pad — a stress-eliminating, body-cosseting comfort zone. Its revival provides strong evidence that upgrading beds is one very direct way to create a true dream house.

Sleeping on Air

Aero, the high-quality air-mattress people, now make an air mattress topper, a two-and-a-half-inch-thick channeled pad that provides a supremely well-cushioned sleeping surface. Once inflated by its built-in electric pump (in about two minutes), the pad's firmness can be instantly adjusted by an inflate-deflate control button (queen and king sizes have dual controls).

The Aero topper fits perfectly on a standard mattress and, once covered by sheets and blankets, no one will know it is there except the blissful sleeper. All sizes, which come with a one-year limited warranty, will hold up to 600 pounds. A quilted fitted cover for the toppers is $49.95. All four sizes, from the $139.99 twin to the $259.99 king, can be purchased directly (http://www.thinkaero.com/).

Memory Foam

Memory foam, a visco-elastic, temperature-sensitive, polyurethane foam, was developed by NASA in the late 1960's to protect astronauts from the tremendous forces experienced during launch. Because it dramatically reduces the stress on pressure points, memory foam was subsequently used by hospitals as padding for bed-ridden patients. More recently, it has become popular as home mattress padding; it simultaneously offers support, particularly for aching backs and joints, and molds to body heat and weight. One excellent brand, Isotonic, is denser and more resilient than most other memory foams. It is available from Healthy Foundations (800#; http://www.healthyfoundations.com/), and all two-inch-thick Isotonic mattress pads are backed by a five-year warranty. Prices range from $99 for a twin size to $185 for a king and include shipping.

Thread Count Is Everything

Fair warning: SmartBargains, an Internet retailer with an ever-changing inventory, can turn perfectly ordinary, practical sheet shoppers into obsessive voluptuaries. The high-thread-count sheets featured at this site — up to 600 and, occasionally, beyond — are sold at astoundingly low prices. The prices and quality, combined with unfailingly helpful customer service, a 30-day return policy and a flat shipping charge of $6.95 per order (regardless of weight) make SmartBargains a must-look site for sheet shoppers. The large selection on the site frequently changes, but recently a 600-thread-count Egyptian cotton sheet set was $109.00 in all sizes; a 400-count sateen set, $69.99; a 300-count damask set, $39.99. All the generously cut sheet sets have one fitted sheet, one flat sheet and one or two pillowcases. They are silky smooth, heavy in the hand, preshrunk and 100 percent cotton. Colors include white and subtle shades like cream, ivory, linen and sand. Devotees monitor the sheet section of this site (http://www.smartbargains.com/) closely; the higher the thread count, the faster they go.

Plug In, Warm Up

Don't think 1950's electric blanket. Today's micro-fiber cloud-light electric covers distribute even, gentle heat via a network of fiber optics, not heavy wires. It's all-night warmth without weight. The new darling of bed buffs, the warmer blankets turn off automatically after 10 hours, are machine washable, can be precisely controlled and, depending on the source, brand and bed size, cost $85 to $200. A brushed-fleece invisible-wire blanket is sold in four sizes and three colors under the Hammacher Schlemmer label (800-321-1484; http://www.hammacher.com/). Other good sources are the Assisted Living Store (888-388-5862; http://www.assistedlivingstore.com/) and Comfort House (http://www.comforthouse.com/; 800-359-7701).