Repointing Slate Steps – Part 2

After repairing the mortar on our back slate steps, it was time to clean and seal them.  There were years [decades?] of moss, algae, & lichen growing on them:

       

I used a scrub brush and bowl of warm water [no soap] and just worked away:

       

After about 4 changes of warm water they were amazingly clean:

The following day I sealed them with the same sealant I used on the front hall slate tiles [Aqua Mix Enrich N’ Seal] [#affiliate]:

It really brought out the colors of the natural stone:

       

And added a weather proof protective layer:

I read that you don’t need to seal outdoor slate steps, and the sealant can in fact make them more slippery in bad weather, but I really wanted them to “pop” instead of looking so old and faded!  Unfortunately the sealant also made old mortar stains “pop”:

       

So. Much. Staining:

       

I blame whoever originally mortared them.

I read up on how to remove staining on slate tile and discovered Aqua Mix sells a product called Nano Scrub [#affiliate].  I tried using it:

But it didn’t really do much.  I think because the mortar stains are so old.  Thankfully the steps still look good:

While using the Nano Scrub I noticed some of my Quikrete joints were cracking:

       

I think because the 2 days I spent using it were both above 90°.  The Quikrete bag said the mortar worked best below 90°.  Oh well… I went back to the hardware store and bought a small tube of Quikrete Mortar Repair [#affiliate]:

I used the whole tube sealing the cracked joins:

       

       

It kind of has a rubbery texture when dry, so the following day I sanded the Mortar Repair down, being careful not to harm the stones:

       

Stay tuned for Part 3 [the final part] where I use Polyblend Grout Renew to darken the Quikrete from cement-color to a more natural grey, and actually start using the steps!