What's less toxic: refinishing an old cast-iron tub or getting a fiberglass tub?

Asked by Christine Stewart
Dallas, TX

What's less toxic for my children who will be sitting in the bathtub: refinishing an old cast-iron tub or getting a fiberglass tub? We would love to get a new cast-iron tub, but it's just not in the budget right now.


Molly McCabe, AKBD, CGP, CAPS

Answered by Molly McCabe, AKBD, CGP, CAPS

Bainbridge Island, WA

A Kitchen That Works LLC

September 16, 2010

Dear Christine,

To answer your question with regard to your children’s skin making contact with either a refinished tub surface or a fiberglass tub surface, there is not much, if anything, to worry about, provided you thoroughly clean either surface prior to the kids using the tub for the first time.

  • Both surfaces are designed to be non-porous.
  • So as long as the kids are not scratching up the tub with die-cast metal toys and you clean it with manufacturer-recommended cleaners, it should remain non-porous.

However, if you are interested in a green bathroom, I think there are several other things for you to consider about your tub options.

  • Let’s begin with the idea of refinishing the cast-iron tub, which I am assuming is not a freestanding clawfoot. From an ecological standpoint, refinishing is the best option. By leaving the tub in place, you will be preserving not only the tub but also the tub surround, hence minimizing materials that would otherwise be destined for the landfill.
  • However, I strongly recommend that you hire a professional refinishing company and not attempt to do the refinishing yourself. This should ensure a proper finish, minimizing chips and cracks and ultimately providing a longer life. Note: you need to provide good ventilation while the refinishers are working and while the finish is curing because at present there are no low/no-VOC products for this application -- it is pretty stinky stuff, and you will want to schedule the work for a time when the least number of people will be around the house.
  • You mentioned that you have a tight budget. Removing the cast-iron tub and purchasing a fiberglass unit has several cost components associated with it:
  1.  labor for removing the cast-iron tub and the tub surround;
  2. disposal of the cast-iron tub and tub surround; and
  3. the cost of the fiberglass unit plus a new surround. What you may not be aware of is that a standard tub, regardless of the material it is made of, typically has a tile flange around three sides of it and that this flange is behind the tub surround wall surface. So if you replace the current tub with a fiberglass one, you will need to replace the tub surround as well.
  • If you prefer a cast-iron tub and you choose a fiberglass one instead, you may end up with buyer’s remorse.  (I am assuming that you really mean fiberglass and not acrylic.)  In my book, fiberglass is a high-maintenance, low-durability material. It can start to look dingy in a short period of time, quickly making it a candidate for replacement and fodder for the landfill.

Choose the tub option that is going to bring you the most satisfaction over the long term.

For more information:

Read Mick Dalrymple's Q&A "I have a bathtub that needs re-enameling. Is there a nontoxic way to do this?"

Tagged In: reuse, durability

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