Not certain if this is the correct forum so maybe a wandering moderator could help me out :D.
What is the best method for cleaning outdoor pavers? These are under a pergola, maybe 15 years old, and are made of concrete. I was thinking Borax- would that do the trick? Maybe Sugar Soap.
Pressure washer.
Rent one for half the day and knock out the sidewalk while you’re at it…or check the local phonebook, usually a kid with his own business that will come and do it for relatively cheap
Not oil or grease- just they have become discoloured from dust and wear and tear.
I am a little concerned about a pressure washer as they are bedded on sand with sand between the pavers rather than grout. I feel if I blast the pavers I may blast all the sand out as well causing the pavers to become loose.
You are right about the pressure washer…concrete will fade after a number of years, the pavers will become smoother and the colour a bit more mellow…if there are specific stains, use dishwasher soap (the granular kind). If not, just give them a rinse with the garden hose. If you are looking for darken the colour back to perhaps what it was, check with your local hardware store about a sealer. Although, in the long run, it will be a maintenance thing.
If the sand between is nicely bedded, you really don’t want to disturb this.
Concrete has a natural aging process … and that’s what this sounds like.
Thanks for the help. There are no spicific stains- there has been a husky living on it for 14 years so that brings some grime from spilled meals. Also the area can be quite dusty.
A pressure washer with a mild detergent/degreaser is your best bet to get them clean.
Don’t worry, if they have been there 15 years, the sand is as hard as concrete. As long as you don’t deliberately blast out the sand between the stones or under the edges, you will be fine.
Even if they become a little loose when water gets under them, they will settle when it dries.
Pressure washer NOT EQUAL pressure washer - some use MUCH higher pressure than others.
Since TSP was withdrawn from the market (hey, what’s a few dead rivers compared to my tidy driveway?), I’ll go with the dishwasher powder - USE GLOVES! Since it is not indende to come in contact with skin, it is nasty stuff.
Also: IF you can apply it ABSOLUTELY evenly - phosphoric acid (if no chemical supply houses, see auto paint stores - it is used as an etcher for aluminum. AGAIN - EVEN distribution.