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Choosing Baths

Baths are available in all shapes, sizes, and materials. I've seen some stunningly beautiful custom bathbaths built out of stainless steel, nickel silver, or even wood, and I've seen square baths, round baths, heart-shaped baths, and even coffin-shaped baths, some of them big enough for the whole family. But for the most part residential bathbaths are either made out of plastic or out of a base metal (typically cast iron or steel) coated with porcelain enamel.

The standard bathbath measures 60 in. long, between 30 in. to 34 in. wide, and 14 in. to 20 in. deep. baths generally can be either freestanding, have one or more aprons so that they can be recessed into corners or alcoves, or be designed to be dropped in (like an overgrown sink) into a site-built platform.

Enameled cast iron baths and steel baths

To my mind, enameled cast-iron is the material of choice for bathbaths. But that doesn't mean that I like moving those things around. Weighing 350 lbs. or more, cast-iron baths aren't easy to haul up a stairway or maneuver through doorways and into tight spaces. When it comes to performance, though, cast-iron baths are hard to beat. The same mass that draws curses when trying to move the thing makes it perfect for holding the heat of a hot-water soak once the bath is in place. Cast iron is quiet when water is running into it, and the smooth, hard porcelain surface is extremely durable and easy to clean. I like it because it feels solid under foot, without that flexing and sponginess you sometimes feel when standing or sitting in a plastic bath. I also like cast iron because it can take a scrubbing and scouring with abrasive cleansers without scratching.

Because of the limitations of the manufacturing process and the weight of cast iron, you won't find it being used for baths with complex shapes or for those that are much bigger than the standard 5-ft. or 6-ft. bath. A traditional cast-iron bath design is the freestanding claw-foot bath, a style that has been popular ever since Kohler introduced the first modern baths before the turn of the century. For a time, these baths were like white elephants, and after being pulled out of a remodeled bath in favor of combination bath/shower units, they were almost impossible to give away. Now, though, antique claw-foot baths that are in good condition are increasingly hard to find, and they fetch top dollar at any of the numerous architectural salvage shops that have sprung up around the country. Of course, manufacturers have now reintroduced these baths in their lines, in both traditional and modern interpretations.

Enameled cast iron does have some drawbacks besides weight, however. On the one hand, the extremely hard porcelain surface is very durable, but if it does get chipped or scratched, it can be almost impossible to repair (although there are proprietary methods of resurfacing porcelain baths that can apply a simulated porcelain-like surface). And for the same reasons that cast iron is good at retaining the heat from hot water, it is also good at remaining cold, especially if the bath is located on a poorly insulated outside wall or in a cold and drafty bathroom. There is nothing quite like the feeling of leaning back while taking a nice hot soak, only to feel the almostelectric shock of a cold bath on your back.

Enameled-steel baths have the look of cast iron but with a considerable weight savings. Once a less expensive and widely used alternative to cast iron, steel baths have been replaced for the most part by fiberglass and acrylic units, although they are still available and often used in hotels and motels. You can also find plenty of them at salvage yards and junkyards. In most cases, you'll find that their thinner enamel coating has worn or chipped away in places, making them not worth salvaging. A recent innovation that combines the durability of cast iron with the lighter weight of steel is American Standard's Americast, which uses an injectionmolded structural foam and metal alloy base for the porcelain-enamel finish that results in considerable weight savings without sacrificing durability or performance.

Plastic Baths

Most people are familiar with gel-coated fiberglass, a material that revolutionized the boating industry. The same qualities that serve it so well in the boat-building industry—strength, light weight, design and construction versatility, and economy—are the reasons that fiberglass has captured such a large part of the bath market. But gel-coated fiberglass also has some problems. The relatively thin and soft gel-coat finish is prone to scratches and abrasive damage. In fact, most abrasive cleaners can't be used with this type of bath without fear of damage to the finish. And the gel-coat finish will tend to oxidize and eventually fade, which is particularly noticeable with some of the brighter colors.

Cast cross-linked thermal-formed acrylic baths have found a niche as a more expensive but more durable alternative to gel-coated fiberglass. The manufacturing processes for both types of baths are similar, and, in fact, both acrylic and gelcoated fiberglass baths use fiberglass as a backing material. The difference is in the first layer, the one that you can see.

Gel coat is a pigmented polyester resin that is sprayed onto a mold in a thin V64-in.-thick layer. Subsequent layers of fiberglass are then added, building up to a thickness of about Vs in. or so. Various "inclusions"—foam, wood or wood composites, or corrugated paper—are added to provide structural rigidity before the unit is popped off of the mold. Acrylic, on the other hand, begins as about a Vs-in. sheet that is heated and vacuum-molded to the form in a process essentially the same as that used by the toy Vacu-forms that were so popular some years back. The fiberglass backing is then applied in the same way, before the bath is popped off the mold. ABS is sometimes used as a less expensive substitute for acrylic.

Compared to cast-iron baths, acrylic and ABS baths are also relatively soft but less prone to scratching than fiberglass. Unlike fiberglass, however, acrylic color is solid, and scratches can be repaired by sanding them out and rebuffing. But significant damage to acrylic or ABS—for example a rupture of the skin—is more difficult to repair than damage to fiberglass. Acrylic is more expensive than fiberglass but less expensive than cast iron, and it is resistant to ultraviolet rays and harsh chemicals.

Another method that is sometimes used in bath manufacture is injection molding. Hot liquid plastic is injected into a hollow mold, then removed when it cools. There are no reinforcing laminations, though there are sometimes sounddeadening undercoatings sprayed on, so the bath's strength is dependent on the strength of the plastic. ABS and acrylic-fortified PVC can be used in this process, resulting in inexpensive and relatively durable baths. My experience with these baths is that their finish tends to dull quickly, and they feel very flexible due to the lack of structural reinforcement.

Flexibility is a problem that is shared by all plastic baths, whether they are laminated or injection molded. While reinforcing and additional layers of fiberglass add strength and rigidity, they also add to the manufacturing cost of the unit. So better-quality—and more expensive—plastic baths will have thicker walls, be heavier, and feel more rigid. Still, I find the give of a plastic bath more than a little disconcerting. It can be more than an aesthetic problem, too: If a plastic bath isn't adequately reinforced under foot and near the drain, the continued flexing is apt to cause the drain connection to loosen, creating a potential point of leakage. Look for adequate reinforcement in this area; also, a field application of mortar between the floor and the underside of the bath can help to stiffen things up. American Standard developed Idealcast, which incorporates an acrylic shell with an injection-molded structural composite underbody, to offer greater structural rigidity than what is normally available in acrylic bath

A relatively new bath material, sheet-molded composites (SMCs) combine polyester resins, chopped glass fibers, and fillers into a strong product that can be molded into one-piece baths. SMCs are more rigid than conventional fiberglass-reinforced baths, but my experience is that they are a bit more susceptible to staining than acrylic. Vikrell (from the Sterling Plumbing Group) is probably the most successful of the SMCs.