You could probably say this about a lot of things, but bathtubs--they just don’t make ‘em like they used to. For the larger part of the last century, bathtubs were formed from cast iron and coated with porcelain enamel. Bathrooms were built around them. These tubs were considerably deeper and thus more inviting than the tubs you'd find nowadays. The dominant color for tubs is white and it is virtually the only way to go.
With the 60s and 70s came the exploration of bathroom fixtures in beige, browns, pastels, and the like. Despite these poor choices, bathtubs in this era were still very well made. While construction shifted to include lightweights like acrylic, tubs in steel appeared, and like the cast irons, these steel tubs were elegant and even sometimes sculptural in design.
Cast iron is generally heralded for its indestructibility, even when rust might set in. It has a close relative in steel, in fact only minor tweaks in composition would turn one into the other. While steel is heavy, cast iron is heavier, and tubs made of these metals ultimately last well beyond their finish.
For just these reasons, you might choose to refinish a tub. While those with a classic clawfoot refinish hope to achieve a vintage feel, any type of tub can be refinished. This article with focus on the redo of an alcove tub, by far the most commonly installed bathtub.
|Tools||Materials||Skill Level||Estimated Time|
|• Utility knife||• Acid-Based commercial cleaner||Advanced||4 to 8 Hours|
|• Putty knife||• Acid etching paste|
|• Straight razor||• Baking soda|
|• Shop Vac||• Plastic sheeting|
|• Stiff bristle brush||• Builders paper|
|• Wire brush||• Masking tape|
|• Auto polisher/buffer||• Abrasive cleaning pads|
|• Buffing and polish pads||• Sandpaper|
|• Respirator||• Canvas drop cloth|
|• Rubber gloves||• Porcelain repair epoxy or polyester glazing putty|
|• Rags and towels||• Two-Part fiberglass repair putty|
|• Paper or shop towels||• Tack cloth|
|• Small mixing trough||• Porcelain bonding agent|
|• Plastic spreaders||• Specialty acrylic urethane OR acrylic aliphatic polyurethane OR white paint and high gloss polyurethane|
|• Electric paint sprayer||• Denatured alcohol|
|• Caulk gun||• Silicone caulk|
|• Plumbing tools|
Bathtub Refinishing Considerations
Off Site or In Place?
As mentioned above, cast iron and steel tubs are extremely heavy, and you’ll need a hand, at least three, to safely remove and deliver them to a refinishing works. In the case of an alcove tub, one that is "built-in," it is usually best to approach it while it is still in place.
A refinishing works may often start with a process called "dipping" or stripping the original finish. Once stripped, your tub may again have a porcelain enamel applied before it is ultimately re-fired in a kiln. Comparable coatings can be applied onsite; stripping, however, is replaced with other means of prep.
Note: Stripping may only be required if the tub had previously been refinished.
Will You Replace Hardware?
Working under the assumption that once (re)finished, you’ll have a new look tub. It may be worthwhile to plan for an update of the tub’s existing drain hardware.
It should be pointed out, too, that the edges are typically the “weakest” part of any finish. In an area constantly subjected to water, it makes sense at minimum to remove the drain prior to applying your new tub finish.
Note: When updating a tub’s drain assembly, access to the lower wall cavity behind the tub drain is required at a minimum.
Consider How You’ll Ventilate
Because, in most cases, you’ll be working with caustic materials and airborne paints, ensure that you have adequate ventilation as you work. Along with running a built-in bath fan, it may also make sense to open a window and utilize cross-ventilation by placing a fan in an opposing doorway. Ventilation equipment may also be rented at home improvement stores or rental centers if additional concerns persist around your ability to work safely or apply paint effectively.
Prepare the Job
There are numerous methods available for effectively preparing a tub refinish. Regardless of the approach you choose, take great care during this phase. The steps below are common to any job preparation approach you might choose:
- 1) Remove Existing Caulk: Remove caulk that should be touching the tub surface. Start by cutting both the top and bottom edges of the caulk bead with a utility knife. Follow with a stiff putty knife and finish with a straight razor blade. Completely remove all existing caulk. Sweep out or vacuum up any debris that may make its way to the bottom of the tub.
- 2) Remove OR Mask the Overflow Plate: Plan to replace existing tub hardware. If this is not feasible, and the tub’s drain is still in good working order, remove the tub’s overflow plate. Tubs fitted with linked stoppers can be disconnected or disassembled, but because of uniquenesses in moving parts (especially with antique tubs), it may be best to simply mask overflow plates off. If you choose to remove a linked lever, be conscious not to allow linkages to fall back into the overflow or drain.
- 3) Remove Drain Pop-Up, Strainer Assembly, OR Mask: Remove as many of the exposed finished drain parts as possible. Mask any finished surface that you choose not to remove. Poke holes or make an X in masking tape to allow for drainage of water as it will be used later in the prep phase.
- 4) Give the Tub an Industrial Cleaning: Using an acid-based cleaner, spray down the entire tub surface. Let the product sit for five minutes and use a stiff-bristled brush to scrub away stains. Because these cleaners are caustic, wear rubber gloves (or better) and a properly rated respirator. Then let the tub dry.
- 5) Mask Off the Tub Area: Using a relatively sturdy plastic, start at the edge of the tub and mask off the alcove walls at least four feet. Mask both the inside of the tub as well as the face (or apron) of the tub as it intersects with bathroom walls. Do the same with the tub as it meets the floor. Cut holes in locations where tub spouts or faucet handles may appear. Apply masking tape prior to spraying.
- 6) Mask Tub Spout and Faucet Handles: While you may need to time this with the other steps below, wrap tub spouts and faucets with builder's paper or additional plastic (cling wrap will work just as well). Alternatively, it may make sense just to remove them.
Prepare the Surface and Make Minor Repairs
Apply an Acid Etching Paste
Use a stiff-bristled four inch stain brush or a scrub brush to apply an acid etch designed specifically for porcelain. Cover the surface of the tub completely and allow about 15 minutes for this product to do its thing. Wear rubber gloves (or better) and a properly rated respirator. Remove with a (clean) scrub brush and wash down the drain with tub water. Wipe dry with shop towels.
Important! Always read labels of chemicals to ensure that they will not interact adversely with any other product you might be using.
Critics of this method point to the fact that these products require neutralization prior to washing down the home’s plumbing drains. To help neutralize an acid etching paste, consider mixing a cup of baking soda into a gallon of water and apply by sprinkling or "misting" over the surface. Apply liberally and allow 10 to 15 minutes of activation time before washing the entire effort down the drain.
Alternatives for Acid Etching
Some will forgo acid etching in favor of applying a bonding agent only. Others may use mechanical means to rough up the tub surface. This is done by way of using sanding (aka flap) discs fitted to an angle grinder. While this method is somewhat aggressive, most finishing products are self-leveling to the degree that they will level out reasonably over a “scarified” surface.
Fixing Tub Surface Imperfections
Grittiness and stains can appear on tub surfaces after decades of improper cleaning. Bleach and abrasive cleaners can be detrimental to tub surfaces, themselves working to etch porcelain. Green stains or rust can be addressed using oxalic acid mixed in hot water with talc to form a whiting paste.
Dings or chips should also be addressed prior to applying a finish. Mix a small batch of two-part fiberglass repair putty and apply to the affected area using a plastic spreader. Allow to dry according to the product’s instructions and sand first with 36-grit sandpaper (the kind used for sanding floors) and then follow with an 80-grit paper to feather out the repair.
If needed, follow with polyester or porcelain glazing to fill in small pockets that may appear in the repaired area.
Wipe down the tub with paper towels first and follow with a tack cloth.
Optional: For a more thorough cleaning, give the tub one final wipe with rapid-evaporating denatured alcohol.
Caution: Only use if acids either were not used or have been effectively neutralized.
Applying Finishes: DIY Approach
There is a seemingly countless array of refinishing kits available from reputable makers. These products vary widely from epoxies to acrylics, spray-on to brush-on and even to roll-on options. In general, you’ll find varying degrees of both dry times and quality with these products. Do your research before purchasing and understand that cost may inform effectiveness over time. Pick a reputable name and follow all instructions closely. These kits should yield a finish lasting one to five years with proper care.
Build Your Own Kit
Brush on an appropriate bonding agent,or spray on an appropriate primer using an airless (sub HVLP) paint sprayer (available for rental at local home improvement stores or rental centers). The topcoat is applied using the same sprayer (make sure to clean it thoroughly between steps). When spraying, hold the gun about six inches from the surface. Work using long strokes and a continuous motion, overlapping slightly as you move back and forth. Play around with a mixture of white paint and high-gloss polyurethane. Alternatively, spray or roll on a two-part marine epoxy. If you haven’t skimped on prep, this method should yield a finish that will last between 3 and 10 years.
Applying Finishes: Pro Approach
Professional refinishers are plentiful, but be warned: the products and techniques used plus their opinions vary widely. It may not be surprising that many pro refinishers started out in trades like auto body repair, where work is often quite personalized.
Acrylic urethane enamel, acrylic aliphatic polyurethane, or an epoxy-based finish is applied in multiple layers using a paint sprayer. (There is much debate online about the preferred sprayer type for this job.n general, choose airless and HVLP over others.) Depending on the product used, each coat should dry 15 to 20 minutes before the next is applied. The final coat should dry for no less than an hour.
A wet sanding with 600/800/1000-grit paper smooths any imperfections. Some use an auto compound buffed into the surface using circular buffing pads and an auto polisher. Additional buffing is often done by hand. Glazing can also be applied with a soft cloth to bring up a more brilliant luster.
Pro jobs often offer a five year warranty, but these products and processes are frequently designed to last up to 15 to 20 years (or the average span between a needed bathroom redo).
Note: It may not always be possible to secure some of the same proprietary products that pros use.
Tear Down and Reinstall Fixtures
Once the finish has dried to the touch, per product recommendations or after two hours, whichever comes first, slowly remove all masking, paper, and plastic from the job site. It is best to work with a utility knife in hand in case any of the newly applied finish begins to pull away with masking. Work with care over the newly finished surface. Bundle waste into construction bags and dispose of appropriately.
After the finish is fully cured, four to six hours or more, reinstall drain and other plumbing components.
Apply a bead of silicone caulk where the tub meets the tile. Use Tub & Tile Caulk for locations where the tub meets the wall or floor.
Find a Pro
While bathtub refinishing can surely be a DIY project, it is often better left to a pro. Pro tub refinishing is simply one of the most practically priced jobs. Prices typically range from $400 to $500 and are usually packaged with a significant warranty.
The most important factor in hiring a pro for this job is the individual technician scheduled to do the work. That’s right, don’t necessarily hire a pro based on the reputation of the company, on their system, or on their process, but rather on the actual individual you would want doing your job. These mechanics should be able to produce a portfolio of work and references. Request it and review it before making a decision.