Removing hair dye, or worse, from tile

Stains may be rust marks, experts tell Jeanne Huber

QOur shower floor is discoloured, probably from rinsing out hair colour. We’ve tried everything — bleach, vinegar, Soft Scrub — and nothing makes a difference. The floor is only seven years old, so we really don’t want to replace it.

AThe stains probably aren’t from hair colour. “You would see it on the walls, too — not just on the shower pan,” said Martin Brookes of the National Tile Contractors Association.

Instead, the stains are almost certainly caused by moisture underneath the tiles, said Brookes and another industry consultant, Donato Pompo. The moisture probably interacted with iron, which is naturally found in some stone tiles, then moved to the surface of the tiles to evaporate, leaving behind rust stains. Stone that may contain iron includes Carrara marble.

A traditional shower floor has a “water in/water out” system. At the base is a mortar bed that slopes toward the drain. Over this goes a waterproofing membrane, also known as a pan liner, with weep holes to channel water into the drain. Over that goes another mortar layer, giving the tile and grout a suitable surface to bond to. This multilayer system assumes water will seep through the tile, grout and top layer of mortar, but the shower pan will then channel it to the drain. The water doesn’t pool for long periods or need to evaporate through the surface of the tile, eliminating the risk of iron stains. But this system works only if there are two mortar layers and if the weep holes aren’t plugged.

To simplify installation, manufacturers also make shower pans designed so installers can attach the tiles directly. But to work, there can’t be gaps where water can pool underneath the tiles. With small tiles, installers need to modify their way of spreading the thinset mortar or other bonding material, Brookes said.

“On mosaic, you need to knock down the ridges so you don’t have peaks and valleys,” Brookes said. “If you don’t, the peaks and valleys don’t collapse — it creates what I call aqueducts. The peaks touch the tile but the valleys hold moisture.”

Products are available that remove rust stains from stone, but if the root problem is moisture collecting underneath, the only solution is to remove the tile and start over.

“Sometimes a contractor can surgically remove the tile and save the membrane,” Brookes said, but often the job calls for a new shower pan.

If the membrane can be salvaged, Brookes recommends using porcelain tile, which is impervious, rather than stone, because iron staining won’t be a problem. But unless you correct the drainage issue, water will still pool underneath the tile and could become more acidic over time, degrading the membrane.

What if you are certain the stains are from hair dye or another spill? For that, Brookes and Pompo recommend using a poultice product — basically a powder plus a liquid that draws out the stain. You mix the two into a paste, spread that over the stain, then cover the poultice with plastic wrap. As the powder dries, it draws in the liquid along with whatever stain it has picked up. When the poultice is dry, brush it off and see whether the stain is gone or at least lighter. Sometimes it takes several treatments.

One poultice product safe to use on marble is StoneTech Oil Stain Remover ($20.35 on Amazon.ca for a three-ounce container).

If you are able to remove the stain, seal the floor with a penetrating sealer.