How to Refinish a Cast Iron Tub

A white, cast iron bathtub.
  • 24-72 hours
  • Intermediate
  • $60-140
What You'll Need
Bathtub refinishing kit
Respirator mask
Scratchy pad
Bleaching pad
Fine grit sandpaper
Masking tape
Paper sheeting

Although refinishing a bathtub is not a typical DIY project, it can be done. Bathtub refinishing kits are sold at many home improvement stores -- if you do it from scratch it may be hard to find the chemicals. Either way, give yourself time because the entire project could take up to three days.

Do the Necessary Prep Work

All successful projects start with great prep. As it turns out, this is the toughest part of the job.

  1. Remove the old drain and trip lever.
  2. Cut away all the old caulk from around the tub.
  3. Clean the tub thoroughly with a scratchy pad and any product that has a bleaching agent.
  4. Rinse well.
  5. Repeat the cleaning using Lime-A-Way or CLR.
  6. Sand the tub with a high grit, wet/dry sandpaper (600 grit or more).
  7. Rinse , rinse, rinse.
  8. Wipe dry to make sure you remove all the grit and remaining water.
  9. Let it dry for several more hours (the tub is porous at this point and needs to be totally dry).
  10. Tape and paper off surrounding areas including the floor next to the tub.

Begin the Refinishing Process

Check the manufacturer’s recommendations on the kit you choose. In most cases, you should wear a respirator mask. The fumes can be very toxic. It would also be a good idea to open windows and put a fan in the window. The fan should be blowing out to pull the fumes from the room. Don’t have the fan blow in or you could incorporate tiny dust particles into your new finish.

In most kits there will be a couple different cans that will need to be mixed together. Make sure that you follow directions. The activator is usually the last can to pour into the mixture. Mix well.

Some kits include applicators, so check the box. If they don’t, then opt for a small foam roller and foam brushes. You will never be able to use the brushes again, so get ones that you can throw away after the project is complete.

This paint is thick and sticky. You will want to roll it on thick (unlike normal painting where you apply several thin layers). The paint dries quickly, so you will have to work quickly. Don’t let the roller become dry. If the roller starts flaking, change to a new roller.

Let the first coat dry completely before applying the second coat. Once the second coat is applied, let it dry for 3-4 days. Leave the tape and papered areas covered, too.

Finishing Up and Some Tips

Put the drain and trip lever back on. Remove tape and paper. Apply new caulk. Voila -- you are done!

Here are some tips that will help your tub maintain a fresh look:

  • Don’t use suction cup mats in refinished tubs because they can damage the finish.
  • Don’t leave wet cloths laying on the tub.
  • Don’t use abrasive or bleach cleaners. Only use soft cloths and spray cleaners.
  • Don’t leave bottles sitting in the corners of the tub. Water accumulates underneath and can damage the finish.
  • DO apply a wax (like gel-gloss) once every four months. Just don’t wax the bottom of tub -- it could get very slippery.

If maintained correctly, your tub will look renewed and refreshed for several years.