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StoneBlock SD125 Moisture and Efflorescence blocker for stone and concrete surfaces


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Location : Interior/Exterior
Task : Block Effloreescence/ Moisture Drive Concrete Stone
Application : Pump Spray/ Roller
Surface : Natural Stone and Concrete
Base : Water Based
Drytime : 1-2 hours
Coverage : 200- 300 sq.ft/gal
Finish : Clear Liquid

Frequently Bought Together

5 gal pail SD125 for blocking efflorescence in concrete stone + 1 gal jug maximum strength stone impregnator sealer +
Price for all three: $519.40

StoneBlock SD125
Blocks moisture and efflorescence in concrete and stone and natural stone surfaces

A mineral-based penetrating solution to block dissolved solids, moisture and salt efflorescence in concrete and stone


  • Blocks efflorescence, water salt migration
  • Reduces water vapor transmission
  • Integral permanent treatment
  • Minimal impact on appearance
  • Consolidates and hardens surface
  • Resists, dissolved chlorides and alkali
  • Workes as a primer for penetrating and topical sealers
  • Speeds up sanding and polishing

Typical Uses

  • Preventing efflorescence in stone and concrete
  • Pre-treatment (6 side) for stone tiles, pavers
  • Treating grout and mortar
  • Minimizing moisture drive in alkali substrates
  • Vapor  reduction
  • Surface hardening of natural stone
  • Excellent primer for stain-resistant sealers
  • Interior and Exterior


1 Gallon (3.8L) bottle  and 5 Gallon (19L) Pail of  Ready To Use Solution


200-300 ft2 per gallon (4.9 – 7.3 m2 per liter) depending on the porosity of the substrate.


Substrates to be sealed must be a minimum of 28 days old and/ or be fully cured. The surface must be clean and porous enough to allow the solution to penetrate the substrate.

Surfaces should be clean and free of surface laitance, dust, dirt, debris, mildew, oil, grease, previous sealers, curing agents, paint or other surface coatings, and other contaminants. If acid or other cleaning compound is used to clean or etch the surface, neutralize the surface completely before applying SD125.

Do not apply StoneBlock SD125 to wet surfaces.

Always test porosity before application, especially on very dense surfaces.   The product is a one-part system.  Stir material thoroughly before and during application. Do not apply below 40°F or above 95°F during the application or drying period.

Apply uniformly with a low-pressure sprayer. When applying material, work in small, manageable areas at a time to maintain a wet edge. The product should be applied
to the point of rejection and be fully absorbed within 10 minutes without puddles.
Use a broom, roller, or microfiber pad to evenly distribute the product as well as disperse any puddles as the excessive application may result in the white residue (especially on
darker or colored surfaces) which will not affect sealer performance and generally dissipates over time or by pressure washing.


Do not apply to wet surfaces.
Do not apply below 40°F or above 95°F (5-35⁰C)
Allow grout and mortar to fully cure before application This product is not a “ topical sealer” and will not prevent staining. Use CoverShield products if you wish to seal and protect from staining.
Do Not Dilute Ready-To- Use Product.
Will not accommodate dynamic movement cracks.
SD125 is designed to work only on porous natural stone and concrete is not intended for asphalt.
The use of high alkaline or acidic cleaners on the treated surface is not recommended and can be damaging.

PDF Downloads

Frequently Asked Questions

SurfaceFinish CD 80 Photos

SurfaceFinish CD 80 Videos

What Is A Stone Blocker 

Natural Stone and Concrete are tough, durable substrates, but they are inherently porous. Salts, dissolved minerals, and moisture can all move to the surface through the pores of the concrete or stone.  The function of Stone Block is to close off this pore system.

StoneBlock penetrates into the surface and reacts with the calcium hydroxide in the stone or concrete, and fills in the voids.  Filling the spaces creates an integral barrier that prevents or minimizes efflorescence, moisture drive, and leaching. 

Furthermore, if you use StoneBlock SD125 prior to sealing you get greater adhesion with topical sealers  and  a boost in repellency  and stain resistance in the case pf penetrating sealers penetrating sealers

What Are The Do’s And Dont’s When Using StoneBlock SD125 Efflorescence and moisture blocker?

When using SD125 , make sure the surface is absorbent or porous. This way, the solution can soak into the substrate.

Any contaminants that are on the surface need to be cleaned off,  stripped or ground off.

Recommended cleaners include SurfaceClean or Surface PrepWork

Recommended Stripper is PowerStrip

Do not over-apply the product. Typically  you should look for between 200-300 ft2
per gallon (4.9 – 7.3 m2 per liter) depending on the porosity of the substrate.

StoneBlock should be fully absorbed into the surface within 10 minutes without puddles.

Using a pump-up sprayer is the best way to apply.

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