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Acrylic, Fiberglass Tub Care and Maintenance

Cast Iron, Acrylic, & Fiberglass Tub and Showers Care & Maintenance

Cast iron and china plumbing fixtures were the only choices you had 50 years ago. Choices were limited as were shapes and designs. However, within the past 15 years, the plumbing fixture market has exploded with new products manufactured using new materials. The visit to the local plumbing supply house that once took only 15 minutes, now may last an hour or more as you try to decide what to select.

Metal Fixtures

Traditional cast iron bath tubs are still available. They are manufactured in virtually the same manner as they have been for close to a century. Molten iron is poured into a mold that is the exact shape of a tub. After the iron cools, the mold is removed. A thick layer of porcelain enamel is fused to the cast iron in a high temperature oven. This enamel coating, as many of us know, is as hard as glass. The finish of a new cast iron finish is brilliant. The biggest difference in today's cast iron products as compared to those of 50 years ago, is the wide variety of shapes and sizes and the seemingly endless color selections. The only person who will be unhappy with your choice will be your plumber, as he or she will have to make an extra trip to the chiropractor! Cast iron tubs are very heavy. I know, as I have installed my fair share of these beasts.

Approximately seven years ago, the American Standard Company introduced a product that offered the durability of cast iron but weighed only half as much as standard cast iron. It is called AMERICAST. It is a metal based product which has a porcelain finish on the topside and structural foam on the underside of each fixture. The manufacturer claims that its finish will outlast that of standard cast iron fixtures. It is supposedly more impact resistant as well. The foam backing is a nice feature if you like to soak in tubs full of warm water. The foam insulates the tub and allows the water to stay warmer for a longer period of time.

Plastic & Fiberglass

The major advancements in plumbing fixture variety and selection occurred with the use of fiberglass and acrylic plastic. These materials allow manufacturers to create an unlimited variety of shapes and sizes.

These units also offered freedom from the use of ceramic tile on the walls of shower stalls and bathtubs. This was a major step forward in making tub and shower areas easier to maintain.

The acrylic and fiberglass units do have their weak points, however. The finish on the products is not as hard as porcelain. Some of the units have thin bottoms which are notorious for flexing when occupied. This flimsy feeling can be eliminated by extra work in the field by the plumbing contractor, or by purchasing a unit which has a reinforced bottom. Extra wood shims or plaster must be placed under the flimsy units to make the base solid. As always, this just adds to the cost of installation.

There are several distinctions in the way these items are manufactured. Virtually every unit uses a backing of some sort to give the acrylic or gel coated top surface more strength. Often, the fiberglass coating is applied by a humanoid. Humanoids don't always produce consistent results on an hour by hour or day by day basis. As such, the backing is not always uniform.

American Standard does make acrylic tub and shower units using a somewhat different process. They call these items IDEALCAST. They take thin acrylic sheets, heat them, bend them to the desired shape and then mechanically apply a structural composite material to the back of the acrylic. The result is increased structural stability.

The Kohler Company has introduced a different plastic compound call VIKRELL. This lightweight plastic compound is similar to acrylic, however it is designed to withstand the alkalies found in soaps and shampoos. These alkalies sometimes cause the colors to fade in other less expensive plastic tub and shower units.

Gel Coated Units

These types of tub and shower units are made by spraying a liquid gel coat on a mold. The thickness of the gel coating is critical. If the proper amount of initiator and temperature is maintained during the curing process, the gel coating can actually achieve a hardness greater than that of the acrylic units.

Surface hardness should be of importance to you. A harder surface can be more easily maintained. It also tends to hold its glossy appearance for a greater length of time.

Repairing Scratches & Nicks

Each of the different products, cast iron, acrylic, and gel coat, react differently to repair attempts. Cast iron, for example, cannot be repaired. If you scratch or nick the porcelain finish, you are simply out of luck. It is really no different than scratching a piece of glass. Acrylic products can be repaired with some difficulty. The repairs, however, are not always invisible. This is due, in part, to the fact that the color is uniform throughout the product. The color is sometimes hard to match.

Gel coated products are the easiest to repair. The repairs, when performed by an experienced individual, are almost always invisible.

Which One is Right?

No matter which type tub or shower unit you decide upon, as long as you purchase a high quality unit, you should be satisfied. There is no overall winner in my opinion.

There are many advantages to the one, two, or three piece plastic units: cost, weight (light!), no grout lines to clean, colors, and various different shapes.

Cast iron tubs and other metal products offer solid, long lasting purchases. They project strength. Their glass like surfaces, when maintained, have no equal.

You make the choice which is right for you and your lifestyle.

Care, Maintenance & Cleaning Tips

The care of cast iron, acrylic, and gel-coated plumbing fixtures is not difficult. The thing that causes the most problems is that people do not clean soon enough. Often a person will wait until a heavy soap buildup or mineral deposit has occurred. When this happens, cleaning with the recommended cleaners becomes a difficult, if not impossible, task. The solution is really very simple. Why not decide to clean the tub or shower area every other Saturday (or other "off" day) while you are showering? Just jump into your birthday suit and get to work! If you do this, you will find that it takes no more than 3 - 5 minutes to completely clean a tub or shower area. The time passes quickly because there is very little to clean! Try whistling as well, as it worked for the dwarfs.

Cast Iron Cleaning Tips

Cast iron fixtures are probably the easiest fixtures to care for, as they have the hardest finish of all plumbing fixtures. The porcelain glaze that is bonded to the iron achieves a hardness very near that of actual glass. We all know that glass, because of its hardness and smoothness is really quite easy to clean. Porcelain, when cleaned on a regular basis, will shine like new glass forever. However, many people simply wait too long to clean things as mentioned above.

Each manufacturer usually prints distinct cleaning instructions and recommended cleaners to use on their products. These instructions are always packaged with the items in new installations. If you have existing fixtures, you can call the 1-800 #s listed in the Acrylic And Fiberglass Shower Manufacturers column to obtain the instructions. Or, if you like, you can contact a local product distributor.

For example, The Kohler Company publishes the following instructions for caring and cleaning of their cast iron products:

  • Do use only non-abrasive cleaners and a soft nylon brush to clean the slip resistant surface of tubs.
  • Do use cleaners with a Ph of between 3 and 8. (Ph is a measurement of how acidic or alkaline a cleaner is.) The following cleaners are recommended: Earth Rite All Purpose, Earth Rite Tub & Tile, Glass Plus, Green Windex, Pinesol Broad Spectrum, Sparkle, Top Job, and Enviro Care Neutral Disinfectant.
  • Do NOT use steel wool, wire brushes, metal scrapers, or abrasive sponge pads!!
  • Do NOT use buffing machines on the slip resistant surfaces on tubs.
  • Do NOT use high alkaline or strong acidic cleaners!
  • Do NOT use abrasive cleaners.

NEVER trust what is published on the label of a cleaning product!!! Always check with the manufacturer to see if the cleaner is OK to use. Some cleaners say "....Safe for all surfaces....contains soft abrasives that are safe for such and such surfaces... Don't believe them!!!!

Acrylic and Gel-Coat Products

 These products are extremely sensitive with respect to the type of cleaners that must be used. You absolutely must contact the manufacturer (if known) to find out what to use. Absolutely never use an abrasive cleaner on these products. Use the mildest soap, like regular dish soap DAWN (not dishwashing machine soap, these have abrasives in them!), that you can find. Clean regularly as stated in the top paragraph of this page. Certain soaps and cleaners can actually fade the color of units. Some soaps contain alkalies that will actually cause cracks to appear in the finishes as well. You must use very mild soaps and clean often! Remember that these fixtures have a softer finish than cast iron products. This means that you MUST use softer cleaning instruments!! The best thing to use is simply a wash rag. Scouring pads of any type will, in all likelihood, leave tiny scratches!

Remember, these units can be waxed. Waxing every three months will keep a bright shine. NEVER wax the floor or bottom of a unit!! The key to maintaining the finish on acrylic and gel coated units is to treat them just like a new car finish. You never use abrasives when you wash your car. The soaps used to clean cars are very mild. Also, I'll bet that you cleaned that new car at least once every two weeks, didn't you???? I thought so. Treat your plastic tub and shower unit the same way and it will look brilliant for many years to come.

Column B65


23 Responses to Acrylic, Fiberglass Tub Care and Maintenance

  1. I have a three piece unit. I have cleaned it and need to put a wax on. I am not sure what I should wax with. Soap and dirt just stickes to the bottom. I'm tired of cleaning it every other day. Maybe you can help me.
    Thanks so much.


  2. I have what I think is a rectangular shaped fiberglass garden soaking tub that is undermounted using tile. It is 20 years old but in fabulous shape (used infrequently) I would like to retile or use stone for a new tub decking look. Some have suggested I just get a new tub because the life of these tubs is limited if I retile/re-stone. Is that necessary. Seems like a waste when this one seems so solid, still has a nice sheen..and not stains or stratches. I would love some advice

  3. I like your site. You addressed my question, however, what kind of wax would I use to treat a non-chipped cast iron sink? It seems to attract dark scratches but they always come clean. You did not recommend repairing it (like a relgazing) in your article. There are no chips, etc. Would a wax restore the finish enough to not look dirty? Thanks, Vicki

  4. I installed a new Acrylic shower and surround and noticed on the instructions to only use cleaners that are safe on acrylic. As an experiment I have been using Turtle-wax car wash soap once a week to clean the shower and glass doors. I squirt some soap on a long handled soft bristle brush I found in the automotive section at Walmart. So far this has worked great. And car wash soap is much milder than dish washing soap. As hard as our water is in this area I am really impressed

  5. How do you remove a buildup of soap scum from an acrylic tub?

    The tub is 7 years old and is cleaned regularly - weekly.

    It seems to be stubborn stain hard to remove.
    Please mention products to use on this tub.


  7. I want to take a special detox bath for a medical condition that I have. It used Epsom Salt and Apple Cider Vinegar as well as some special calcium bentonite clay. Would this harm my bathtub? (Whirlpool - acrylic) I don't need the jets, I'm thinking that would not be good, but what about the actual tub?

    • Very carefully with a sharp straight-edged razor blade. I also have a column here on my website that tells you the household chemical to use to dissolve the small about of residual silicone. Use my Search Engine to locate it.

  8. sorry...I meant, if we wanted to use epsom salts for bathing for dry skin would it be safe for the finish of the acrylic bathfitter insert?

  9. I have acrylic bath tubs. You mentioned in previous posts that I can wax the finish. What wax should I use? Also, is a soft sponge with liquid clothing detergent (Tide Free and Gentle) safe to use?

    Thank you

    • Lori, any high-quality car wax is great. Realize it will make the tub SLIPPERY!!!!! Use a high quality rubber mat to avoid falls. Any soap is safe so long as there are no abrasives in it.

  10. Hi,
    I have a full surround that is about 20 years old and in great condition with the exception of being VERY dull. We installing new vanity and tile floor but I don't have the heart to discard the surround since it's still in great shape. What is the best way to bring back the shine?

  11. The shower in my RV is stained a brownish colour. There is a white line where the hose rests again the shower wall or where I left my shampoo bottles. Below the decorative lip to the floor of the shower it still is the original white aswell. It seems to be only where the light from the sun dome reaches the acrylic. Anything I can do other than replace the whole unit?

  12. I have a new Kohler shower that has some damage. It's fiberglass with a coating on it. The coating is not gel coat - it appears to be some sort of plastic. When I experiment with paints and gel coats it causes the area surrounding the damage to wrinkle and lift. How can I fix it?

  13. We just moved to a home with acrylic one piece shower/tub. It appears the previous owner used some abrasive cleaner as the shine is gone and looks like swirls in the surround. It's there a way to restore the shine and get rid of the swirl marks? This unit is in great shape except for thIs. Any suggestions?

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