How to remove Sandstone paver stain?

OliverK

Just recently moved into a new house which has outdoor sandstone veneer pavers which when dry are not to bad, but when wet look terrible!

I have tried chlorine (12%) left on then for an hour which helped clean up some of the dark stains, however these stain (dark red) remain and are usually around moisture exposed areas. Could it possible be an iron stain? Any advise and what to use would be appreciated.

Pressure washing would do nothing for this as these stains are deadly embedded into the paver

MitchellMc

Welcome to the Bunnings Workshop community @OliverK. It's wonderful to have you join us, and many thanks for your question about paving.

Moving into a new place is always exciting, though dealing with tricky stains can be frustrating, so kudos for tackling it head-on! From what you’ve shown, it’s a bit tricky to say exactly what the dark stains are. They could be iron stains, which typically come from nearby iron sources like rebar and usually show up as more isolated spots. However, given the widespread nature around moisture-prone areas, it’s quite possible these stains come from tannin-rich leaves or organic matter that have fallen and leached into the stone over time.

Once these kinds of stains penetrate deep into sandstone, they can be incredibly difficult, and sometimes impossible, to fully remove—even with chlorine treatments or pressure washing. If the staining continues to bother you, one practical option to consider is coating the area with a paver paint. This can help give the surface a uniform, clean appearance and protect against future staining. Here's a helpful guide: How to paint concrete floors.

You’re already making great progress by trying treatments, and with a little more work or protection, your pavers can look fantastic again. Keep up the great work — outdoor spaces take time to perfect, but it’s well worth the effort!

Please let me know if you have any questions.

Mitchell