Solving ‘Marble Mysteries’ – Regrouting Marble Shower Floor and Walls

Marble shower Hingham before regrouting - green copper leaching
Marble shower Hingham before regrouting – green copper leaching
Marble shower Hingham with green copper leaching close up before regrouting
Marble shower Hingham with green copper leaching close up before regrouting
Regrouted and cleaned marble shower bench Hingham - green copper gone
Regrouted and cleaned marble shower bench Hingham – green copper gone

Sometimes stone maintenance can be a little bit hard to figure out – a ‘marble mystery’.

We got a call from a homeowner in Hingham, a suburb on Boston’s South Shore, who was frustrated with the look of his marble shower.

You can click on the before and after pictures to get a better resolution photo.

It was a beautifully installed stone shower, but he had noticed that some sort of green residue was showing on grout lines near the shower bench and onto the floor of the shower. It wasn’t mold, it wasn’t any form of cosmetic dye…at first we couldn’t figure out what it was at all.

Then the homeowner recalled that the original installers had run the copper shower pan liner up to and under the shower bench as a waterproofing measure. This is not the standard way to do it, but we have seen it done that way on occasion.

So over time the green copper ‘rust’ had leached through the grout lines and permeated the grout. Fortunately the marble itself wasn’t discolored. Technically, copper doesn’t ‘rust’, but it ages with a green color – think of the Statue of Liberty.

The marble didn’t need any diamond honing or polishing, so that was not part of the solution.

The Plan of Action: Steps to Regrouting the Marble Shower

1. Clean the marble shower surfaces with non acid, marble safe cleaning liquids
2. Regrout the walls of the shower with traditional non-sanded grout
3. Recaulk corners and edges
4. Regrout the sanded grout floor of the shower to remove the green discoloration
5. Apply clear penetrating sealer to protect the stone and grout

Regrouting marble shower walls is fairly standard work – we do it every week. But regrouting marble shower floors with sanded grout is not something that always needs to be done; the sanded grout is difficult to remove without using special grinding tools with diamond tipped blades. Still, we’ve done enough of them to know the process and it came out looking nifty and clean – no sign of green, just fresh new grout, clean marble and a ‘new’ look to a beautiful marble shower restored to its original appeal!

If you have a ‘marble mystery’, feel free to give us a call or text at 617-221-4002 or just fill out the form below with your contact information.

Our contact information:

Act One – Marble and Tile
15 Main Street # 138
Watertown MA 02472-4403
617-221-4002 Text or Call