---
product_id: 8120729
title: "300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon"
brand: "chimneyrx"
price: "A$156"
currency: AUD
in_stock: true
reviews_count: 8
url: https://www.desertcart.com.au/products/8120729-300119-masonry-chimney-water-repellent-siloxane-based-non-film-forming
store_origin: AU
region: Australia
---

# Long-lasting chemical bond Penetrates 1/4 inch deep Breathable, non-film barrier 300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon

**Brand:** chimneyrx
**Price:** A$156
**Availability:** ✅ In Stock

## Summary

> 🧱 Seal Smart, Stay Dry, Look Sharp!

## Quick Answers

- **What is this?** 300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon by chimneyrx
- **How much does it cost?** A$156 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.au](https://www.desertcart.com.au/products/8120729-300119-masonry-chimney-water-repellent-siloxane-based-non-film-forming)

## Best For

- chimneyrx enthusiasts

## Why This Product

- Trusted chimneyrx brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Breathe Easy, Stay Dry:** Allows moisture vapor to escape, preventing damage
- • **Built to Last Through Seasons:** Durable protection against freeze-thaw cycles and water damage
- • **Invisible Armor for Your Chimney:** Siloxane formula penetrates deep without altering appearance
- • **Coverage That Works With Your Schedule:** Covers 40 sq. ft. per gallon, dries fast for timely protection
- • **Effortless Application, Instant Confidence:** Spray on easily with quick 2-coat process and simple cleanup

## Overview

This 1-gallon Siloxane-based masonry water repellent deeply penetrates up to 1/4 inch into brick and concrete surfaces, creating a breathable, transparent barrier that prevents water damage without changing your chimney’s look. Designed for easy spray application and quick drying, it offers durable, long-lasting protection against moisture, freeze-thaw damage, and scaling—perfect for maintaining the integrity of vertical masonry surfaces year-round.

## Description

Full description not available

## Features

- ADVANCED SILOXANE FORMULA: Siloxane masonry sealer deeply penetrates up to 1/4 inch into masonry and concrete, creating a strong, breathable water repellent barrier that provides lasting protection without altering the appearance of brick or stone
- BREATHABLE PROTECTION: Unlike film-forming sealers, ChimneyRx waterproof sealer allows water vapors to escape, preventing trapped moisture, which leads to spalling and scaling, while reducing the risk of freeze-thaw damage during colder months
- DURABLE & LONG LASTING: Our chimney waterproofing sealant forms strong chemical bonds beneath the surface, becoming a part of the physical structure, providing long-lasting protection against water damage to chimneys, ensuring years of defense
- EASY APPLICATION & CLEANUP: Apply the chimney sealer with a pump or airless sprayer; lay a drop cloth around the base, spray from the bottom up, and cover thoroughly; apply a second coat within 3-5 minutes; cleanup is easy with just soap and water
- DRY TIME & COVERAGE: This masonry sealant covers approximately 40 sq. ft. per gallon; apply in temperatures between 40-90°F, allow 2-6 hours drying time depending on humidity for optimal protection (apply at least 6 hours before rainfall)

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Controls Type | Push Button |
| Specification Met | rx |
| Ventilation Type | Ductless/Recirculating |
| Vent Hood Design | Wall Mounted Canopy Hood |
| Manufacturer | CHIMNEYRX |
| UPC | 709057221283 |
| Part Number | 300119 |
| Item Weight | 8.49 pounds |
| Product Dimensions | 7 x 4 x 12 inches |
| Is Discontinued By Manufacturer | No |
| Size | 1 Gallon |
| Item Package Quantity | 1 |
| Special Features | Waterproofing |
| Batteries Included? | No |
| Batteries Required? | No |

## Product Details

- **Brand:** CHIMNEYRX
- **Product Dimensions:** 4"D x 7"W x 12"H
- **Special Feature:** Waterproofing
- **Material:** concrete
- **Mounting Type:** Wall Mount

## Images

![300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon - Image 1](https://m.media-amazon.com/images/I/61Ca-L4xA2L.jpg)

## Questions & Answers

**Q: Can I use this to seal the top of my chimney?**
A: This product is for sealing bricks which is fine for the brick part of the chimney. For the crown you should use this product; http://www.amazon.com/ChimneyRx-Brushable-Masonry-Fireplace-Repair/dp/B004XJYJBA/ref=sr_1_1?s=hi&ie=UTF8&qid=1459433037&sr=1-1&keywords=ChimneyRx+Brushable+Masonry+Fireplace+Crown+Repair

**Q: is this product made by system savers in richmond indiana?**
A: Yes it is!!!

**Q: It says vertical surfaces.  I wonder if I can use it on our brick front stoop and steps?**
A: It works on vertical and horizontal surfaces but is designed to shed water from vertical surfaces better and won't protect from standing water on horizontal surfaces.

**Q: Is this available in larger quantities ?**
A: No, it is not available in larger quantities.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Repares the chimney leak
*by A***N on February 23, 2025*

My brick chimney started leaking after 30+ years. Use of chimney cleaner and sealant made the job and fixed the leak and water stains formation! Great product, may be overpriced, but make the job. I recommend this product.

### ⭐⭐⭐⭐⭐ These pieces should be tapered so that they will be easily removed after casting the new cement
*by G***F on November 7, 2016*

I had water leaking into my family room through the chimney. For some reason the upper ten rows of brick had become porous and with some occasional cracks. The real problem however was the cracked crown. The chimney footprint is approximately 65 inches by 30 inches.I removed the old crown by cutting grooves using a 4" diamond wheel in a small right angle grinder and chiseling off the old cracked crown. I screwed together a wooden form for the new crown so that it now overhangs the chimney by 3" on all four sides and approximately 2-1/2 ' thick at the edges. a drip groove was made using 1/4 x 1/4 wide wooden strips nailed to the bottom of the form approximately 3/4' from the form's walls.These pieces should be tapered so that they will be easily removed after casting the new cement. I used high strength cement tapered upward toward the chimney flue. Two layers of corrugated cardboard were used to create a space between the new cement and the flue. After casting the cardboard was removed and the space filled with silicone caulk. This is critical to allow for thermal expansion and contraction. The worst part of the job was hauling the 800 lbs of wet cement to the roof. Fortunately I own a ranch house and from my deck to the roof is only about 11 feet. I rented a a lift for the day that was easily hand cranked up to the roof line. It was well worth the price.After repairing all the broken and missing mortar joints I sprayed the entire chimney with the chimney water repellent using a garden sprayer. This process was very easy . My bricks were so "thirsty" that I ran out of liquid halfway through the job. Fortunately I started half way up the chimney side and worked my self up to the crown. I was just able to cover the top half with two coats.I followed this by filling minor cracks with the Masonry Crack and Joint Sealer made by the same company.I highly recommend both products.

### ⭐⭐⭐⭐⭐ Easy to apply
*by J***I on July 23, 2024*

I just applied it, so have no idea how well it works. It was easy to apply though and a gallon goes a long way. You should only need one gallon. This product seeps into the cement/concrete, then hardens. It's not meant to seal cracks or anything. You will need to apply a lot to be sure plenty has soaked in. I plan to use this on my sea wall in the fall.

## Frequently Bought Together

- ChimneyRx 300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon
- ChimneyRx 300014 Brushable Chimney Crown Repair – Elastomeric & Waterproof Coating for Crowns & Masonry - Fast-Setting & Long-Lasting Protection Crack & Leak Prevention - 1 Gallon

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*Product available on Desertcart Australia*
*Store origin: AU*
*Last updated: 2026-02-25*