Pressure wash wall grout?????

I thought of the exact thing a week ago--but I was also wondering if it would be too much!!

Sijka

I think you could do some real damage with the PW, especially if it is un-sanded grout. If it is that dirty and stained, I would consider re-grouting and then sealing

____Reply Separator_____ But then you'd have to remove the old grout to re-grout. Wouldn't the power washer do this? Either way, you either have clean old grout, or you're ready to re-grout.

Old grout is removed with a grout saw or a rotary tool (Dremmel or Roto Zip). There isn't any water involved. Intact, unsealed grout can allow as much as 20% water infiltration to the substrate. I would assume that a PW would increase that since it isn't static pressure. Depending on the substrate, you could cause significant damage. If the tile is set in a mortar bed or cement backer board, then you would be in relatively good shape - although the backer board might wick water to the studs and insulation causing a problem. Green board or gypsum board could be ruined. I had a shower that I thought simply needed to be regrouted in couple of places. When I started to remove the grout, tile came lose. Then it was apparent that large areas of green board were wet. When that was removed, I found wet insulation and studs, with a significant amount of mold. Before it was all over, I had to gut the room, replace the insulation, put up a moisture barrier, apply cement backer board, tile, and re-set all the fixtures including a large jetted soaking tub. Of course, it is your bathroom.

____Reply Separator_____ Thanks for the advice. I do know that the tile is on concrete wall board. Each