Limestone patio...and flagstone

Next request, longtime customer of mine just renovated a house and she has a ton of limestone that needs cleaning…and sealing.

  1. What pressure nozzles for my SC

  2. What sealer works for this and how is it applied.

I did a search, one post said ‘run away’ lol.

that looks like tile

It’s limestone.



Too much pressure!:rofl:

I’m curious too @dcbrock

Is there any organic growth on there?

No, it’s all brand new from the renovation and just lots of muddy boot prints. There’s an entire back patio of the stuff, along with a back walkway and front porch. I’m guessing at least 1500 sq/ft, will measure tomorrow.

Also there was a couple planters out front and a couple spots got scratched, not sure what she can do with that.

maybe someone else can confirm but maybe an application of NMD80 on the whole thing would clean it up really good.

I’m not rying to get rid of efflorescence, it’s just dirt. The trick is using the proper nozzle size and what to seal it with.

mwpws is spot on… With new construction workers track clay all over the place. Honed limestone should clean up good with Onerestore or NMD80.

Just wash it at low pressure with your surface cleaner first… if the boot stains remain, use a buffered acid like Onerestore

I like OneRestore if needed on limestone.

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Ah ok, got it. What pressure should I use, and any ideas about sealing?

Natural base sealer, non solvent. Can be applied pump up sprayer or 12v sprayer…

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Low pressure, high volume. 1-2k. 4+gpm. 25-40+ tip size. Use Siloxane PD to seal. Spray on until saturated. Dries unnoticeable until it rains and beads the water.

Edit- for a surface cleaner, the wider the better.


Siloxane PD is WB sealer, & should work well with the natural stone… good luck!


You guys rock, thank you!

Looks like a local retailer sells Prosoco Sure Klean PD, I’ll give them a call tomorrow. I will probably need four 40035 tips if I’m doing the calculator correctly. Right now I have 25025’s getting 2500-ish psi.

OK, listen up. Typically on newer installs like this one, you want to hit it with the nmd80 because there are usually some mortar smears or glaze from the polymeric sand if they used that. It will also get rid of the mud stains from people tracking on it. Do not do this job until everyone else is out of the way, including landscapers. You need to be the last man standing.

Buy one of the nmd80 sprayer attachments, makes it stupid easy. Once you spray it on there, let it dwell about 10min and then spray again. don’t let it dry. If not real dirty, then you may be able to get by with one application. 1500 ft you may go thru 10gal. About $80 for a 5gal here. Rinse off with light - medium pressure unless you’re just doing small area at a time. Then start surface cleaning. I leave my injector bypass on which lowers my psi to about 2000psi and you’ll be perfect. Rinse really well. Even though you’re not doing joint stabilization on this one, I still like letting it dry for a day. In fact carry your blower with you to blow off excess water and you’ll need even during the sealing phase, to gently blow out any puddles or excess while sealing.

Here’s sealer I use. Surebond Sealers | SEK SUREBOND  |  Hardscape Installation & Protection
You can find nationwide - can click on any of the red boxes for further description. I use the 8700 a lot and it works great on limestone.

On a job this big, you probably want to build you a little portable 12v system using 2.2 gpm pump. Here are pics of both of mine - notice the Chapin sprayer nozzle and wand I took pics of. Can get from Grainger. Just sent all these pics to @DisplacedTexan.


Forgot to ask you what sealer you like. Bookmarked that link for the morning. Thanks Rick

@DisplacedTexan what have you got up your sleeve to be needing those pics…

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