---
title: "Technical Bulletin #1"
description: Learn how water-repellent sealers and waterproof coatings impact efflorescence on masonry walls. Discover the best practices for prevention and maintenance.
---

[![RainguardProLogo](https://blog.rainguardpro.com/hs-fs/hubfs/RainguardPro%20Logo.png?width=1262&height=645&name=RainguardPro%20Logo.png "RainguardProLogo")](http://rainguardpro.com)

Open main menu Close main menu

- [Home](https://rainguardpro.com/)
- [Newsroom](https://blog.rainguardpro.com/newsroom)
- [Project References](https://blog.rainguardpro.com/projects)

[Learning](https://blog.rainguardpro.com/newsroom/tag/learning)

# Technical Bulletin #1

[RainguardPro](https://blog.rainguardpro.com/newsroom/author/rainguardpro)

[Share this blog post on Twitter](https://twitter.com/intent/tweet?text=I+found+this+interesting+blog+post&url=https://blog.rainguardpro.com/newsroom/technical-bulletin-number-one) [Share this blog post on Facebook](http://www.facebook.com/share.php?u=https://blog.rainguardpro.com/newsroom/technical-bulletin-number-one) [Share this blog post on LinkedIn](http://www.linkedin.com/shareArticle?mini=true&url=https://blog.rainguardpro.com/newsroom/technical-bulletin-number-one)

### Water Repellent Sealers vs. Waterproofer Coatings: Impact On Efflorescence

Efflorescence, the white, powdery substance on masonry walls, can be unsightly and structurally damaging. Understanding the role of water-repellent sealers and waterproofing coatings in efflorescence prevention is crucial for builders and homeowners. This report explores the differences between these two protective treatments and their effects on masonry substrates.

What Is Efflorescence?:  
Efflorescence is a crystalline deposit that forms on the surface of masonry walls due to soluble salts in  
cementitious building materials. When these materials come into contact with water, the salts dissolve and  
migrate to the surface, producing the characteristic white powder. Water sources can include rain, high humidity, or groundwater levels.

Water Repellent Sealers:  
Function: Water-repellent sealers penetrate the masonry substrate, creating a hydrophobic barrier. They allow water vapor transmission while preventing liquid water intrusion.

Effect on Efflorescence: Positive. Penetrating water repellents minimize efflorescence problems by reducing water intrusion.

*Caution: Film-forming barriers (such as coatings) can cause efflorescence or sub-fluorescence issues. Water repellents will not waterproof or prevent ponding water on horizontal masonry from penetrating; thus, water will naturally enter the substrate. This is where waterproof coatings excel.*

Best Practice: Ensure the wall maintains its natural rate of water vapor transmission to promote drying before mobilizing stains.

Waterproofer Coatings:  
Function: Waterproofer coatings create a film on the masonry surface, forming a barrier against water  
penetration.

Effect on Efflorescence: Positive. Coatings can provide excellent waterproofing.

*Caution: Film-forming coatings may trap moisture within the substrate, leading to efflorescence or premature coating failure such as bubbling, cracking, or peeling.*

Best Practice: Choose coatings that allow some breathability to prevent moisture entrapment.

Comprehensive Approach:  
The most effective strategy involves a combination of both treatments.

Water Repellent: Seal vertical porous masonry to help shed water when it rains or splashes while remaining  
highly breathable for easy maintenance and longevity.

Waterproofer: Use on horizontal ledges, sills, or caps. This will prevent ponding water from penetrating when dwelling for longer periods. It is also ideal for crack bridging hairline cracks in vertical or horizontal applications.

In conclusion, efflorescence prevention requires a thoughtful selection of protective treatments based on  
the conditions on a job site. While water-repellent sealers allow masonry to breathe and minimize efflorescence, waterproof coatings can provide robust waterproofing. A holistic approach combining both methods ensures optimal results for masonry substrates.

#### Efflorescence Solutions

| [![RP-1101 Restore-N-Prep (32 oz) Makes 1 Gal](https://blog.rainguardpro.com/hs-fs/hubfs/RP-1101%20Restore-N-Prep%20(32%20oz)%20Makes%201%20Gal.jpg?width=1000&height=1000&name=RP-1101%20Restore-N-Prep%20(32%20oz)%20Makes%201%20Gal.jpg)](https://rainguardpro.com/products/restore-n-prep) Learn more about [Restore-N-Prep](https://rainguardpro.com/products/restore-n-prep) | [![CR-0701 Micro-Seal (1 Gal) Makes 10 Gal](https://blog.rainguardpro.com/hs-fs/hubfs/CR-0701%20Micro-Seal%20(1%20Gal)%20Makes%2010%20Gal.jpg?width=3000&height=3000&name=CR-0701%20Micro-Seal%20(1%20Gal)%20Makes%2010%20Gal.jpg)](https://rainguardpro.com/products/micro-seal) Learn more about [Micro-Seal](https://rainguardpro.com/products/micro-seal) | [![EB-0105 Efflorescence Blocker (5 Gal)](https://blog.rainguardpro.com/hs-fs/hubfs/EB-0105%20Efflorescence%20Blocker%20(5%20Gal).jpg?width=3000&height=3000&name=EB-0105%20Efflorescence%20Blocker%20(5%20Gal).jpg)](https://rainguardpro.com/products/efflorescence-blocker) Learn more about [Efflorescence Blocker](https://rainguardpro.com/products/efflorescence-blocker) | [![CR-0201 Blok-Lok (1 Gal)](https://blog.rainguardpro.com/hs-fs/hubfs/CR-0201%20Blok-Lok%20(1%20Gal).jpg?width=1000&height=1000&name=CR-0201%20Blok-Lok%20(1%20Gal).jpg)](https://rainguardpro.com/products/blok-lok) Learn more about [Blok-Lok](https://rainguardpro.com/products/blok-lok) |
| --- | --- | --- | --- |

<https://linkedin.com/company/rainguard-brands/> <https://www.facebook.com/RainguardPro/> <https://www.instagram.com/rainguardpro>

 

## Related Articles

[![](https://blog.rainguardpro.com/hubfs/Rainguard%20PCI.png)](https://blog.rainguardpro.com/newsroom/rainguard-brands-acquires-precision-coatings-inc)

[Press Release](https://blog.rainguardpro.com/newsroom/tag/press-release)

### [Rainguard Brands Acquires Precision Coatings Inc.](https://blog.rainguardpro.com/newsroom/rainguard-brands-acquires-precision-coatings-inc)

#### Rainguard Brands, LLC of Phoenix, Arizona, to Acquire CACG Missouri, LLC dbaPrecision Coatings, Inc. of Joplin, MissouriPhoenix, Arizona - August 2, 2024

Rainguard...

[RainguardPro](https://blog.rainguardpro.com/newsroom/author/rainguardpro) 

[Read More](https://blog.rainguardpro.com/newsroom/rainguard-brands-acquires-precision-coatings-inc)

[![choosing-water-repellent-pic](https://blog.rainguardpro.com/hubfs/Water-Repellent-Pic.jpg)](https://blog.rainguardpro.com/newsroom/choosing-the-right-rainguardpro-water-repellent)

[Products](https://blog.rainguardpro.com/newsroom/tag/products)

### [Choosing the Right RainguardPro Water Repellent](https://blog.rainguardpro.com/newsroom/choosing-the-right-rainguardpro-water-repellent)

What is the difference between RainguardPro water repellent products? It may seem confusing when you browse our wide selection of water repellent products available on[...](https://rainguardpro.com/)

[RainguardPro](https://blog.rainguardpro.com/newsroom/author/rainguardpro) 

[Read More](https://blog.rainguardpro.com/newsroom/choosing-the-right-rainguardpro-water-repellent)

#### About Us

- All Products
- New Products
- Who is RainguardPro?

#### Resources

- All Resources
- Safety Data Sheets
- Technical Data Sheets

#### Contact Us

- Send a Message
- Start a Chat
- Give Us a Call

[Follow us on Facebook](https://www.facebook.com/rainguardpro) [Follow us on LinkedIn](https://www.linkedin.com/showcase/rainguardpro) [Follow us on Twitter](https://www.twitter.com/rainguardpro) [Follow us on Instagram](https://www.instagram.com/rainguardpro)

```json
{
  "@context" : "https://schema.org",
  "@type" : "BlogPosting",
  "author" : {
    "@type" : "Person",
    "name" : "RainguardPro",
    "url" : "https://blog.rainguardpro.com/newsroom/author/rainguardpro"
  },
  "dateModified" : "2024-07-31T15:39:44.713Z",
  "datePublished" : "2024-07-30T22:57:28.000Z",
  "headline" : "Technical Bulletin #1",
  "mainEntityOfPage" : {
    "@id" : "https://blog.rainguardpro.com/newsroom/technical-bulletin-number-one",
    "@type" : "WebPage"
  },
  "publisher" : {
    "@type" : "Organization",
    "logo" : {
      "@type" : "ImageObject",
      "url" : "https://blog.rainguardpro.com/hubfs/RainguardPro%20Logo.png"
    },
    "name" : "Rainguard Brands, LLC"
  }
}
```