Answering how to protect brick walls from water intrusion, these products offer breathable, durable barriers that prevent leaks while preserving brick texture. Ideal for homeowners, contractors, and DIY renovators seeking long-lasting masonry protection for exterior chimneys, basements, and brick facades.
Summary of selected products:
| Product | Brand | Best For | Key Benefit |
|---|---|---|---|
| Thompson’s WaterSeal Multi-Surface | Thompson’s Store | Exterior wood and masonry surfaces | Clear waterproof stain with UV resistance |
| MasonryDefender Chimney Brick Sealer | MasonryDefender Store | Chimneys and vertical masonry | Breathable siloxane sealant that won’t alter color |
| Stormdry Brick Sealer | Stormdry Store | Brick, stone, and masonry walls | 25-year protection with deep penetration |
| ChimneyRx Masonry Sealer | CHIMNEYRX Store | Brick chimneys and vertical surfaces | Siloxane sealer with deep, breathable penetration |
| KILZ Basement and Masonry Paint | KILZ Store | Interior/exterior masonry walls | Nanotechnology water barrier for strong protection |
Thompson’s WaterSeal Multi-Surface Stain, Clear
Best for: exterior brick or masonry that also needs a clear finish with color protection. This product acts as both a waterproofing stain and a wood-friendly sealer, helping seal pores on concrete, brick, and other exterior surfaces while preserving natural texture. Ideal for areas where you want a transparent finish that still reveals surface texture.
Why it was selected: It combines waterproofing with a clear stain that reduces UV damage, helping maintain appearance and longevity in sun-exposed brick facades. The polymers form a fade-resistant layer that resists weathering over seasons.
Caution: It hides grain while maintaining texture, so it may not provide a fully uniform color on highly textured bricks. Ensure surface is clean and dry before application.
MasonryDefender Chimney Brick Sealer
Best for: brick chimneys and vertical masonry surfaces requiring a breathable water proofer that does not change surface color. This siloxane-based system bonds with masonry to provide durable protection while allowing trapped moisture to escape.
Why it was selected: It emphasizes a permanent bond and moisture management, reducing the risk of freeze/thaw damage in cold climates. The product supports long-term durability without film formation that hides texture.
Caution: As a sealant that preserves color, it may not dramatically darken or alter appearance; plan expectations accordingly if you want a noticeable finish change.
Stormdry Brick Sealer
Best for: brick, stone, and other masonry surfaces needing deep penetration with long-lasting protection. This cream-based formula forms an invisible barrier after a single coat and is highly resistant to penetrating damp.
Why it was selected: The product offers a 25-year protection profile and breathability, which helps masonry dry naturally while preventing water ingress. It is suitable for exterior walls and above-grade masonry where permeability is essential.
Caution: Not recommended for limestone or surfaces that are already painted. Confirm substrate compatibility before application.
ChimneyRx Masonry Sealer
Best for: brick chimneys and vertical masonry that require a breathable, non-film-forming shield. The siloxane-based formula penetrates deeply to create a durable water repellent barrier without altering appearance.
Why it was selected: It emphasizes deep penetration and ongoing breathability, reducing the risk of moisture buildup that can lead to spalling or frost damage in exterior brick structures.
Caution: Applications should be performed with proper ventilation and following surface preparation guidelines for best results.
KILZ Basement and Masonry Waterproofing Paint
Best for: interior or exterior masonry walls that need a combined paint and waterproofing action. The nanotechnology-based barrier blocks water pressure and protects against moisture intrusion.
Why it was selected: It offers versatile indoor/outdoor use and a durable finish resistant to moisture and alkali. This can be a practical option when painting and sealing in one step is desired.
Caution: Not for floors or areas with active leaks; ensure proper surface preparation and crack filling before painting for best results.
Buying Guide: Key Considerations For Waterproofing Brick
- Surface compatibility: Determine if the product is suitable for brick, mortar, or mixed masonry and whether it’s intended for interior or exterior use.
- Breathability: Choose breathable sealers to prevent trapped moisture that can cause spalling or freeze/thaw damage.
- Penetration depth: Deeper penetration generally offers longer-lasting protection, but check if a surface film is desirable or not.
- Color and texture: Decide if you want a clear finish, a tinted stain, or a paint-based barrier that changes appearance.
- Durability: Consider climate exposure, such as freezing winters, sun exposure, and humidity, which influence how often reapplication is needed.
- Application method: Some products are spray-on, while others require brushing or rolling. Follow surface prep steps like cleaning and crack filling.
- Substrate limitations: Avoid products labeled as not suitable for limestone, painted surfaces, or active leaks unless compatible with your brick type.
Frequently Asked Questions
- What is the difference between a penetrating sealer and a film-forming sealant?
A penetrating sealer soaks into masonry to repel water while maintaining breathability; a film-forming sealant creates a surface coating that can alter the appearance and may peel if moisture is trapped. - Should I seal my brick chimney?
Yes, a breathable siloxane or similar water repellent designed for masonry can protect against leaks, freeze/thaw cycles, and dampness without changing the surface color. - Can I use interior paint for exterior brick waterproofing?
Some products combine paint and waterproofing for interior/exterior use, but ensure the surface is prepared and appropriate for outdoor exposure before applying. - How often should brick waterproofing treatments be reapplied?
Reapplication intervals vary by product and climate; many sealers last several years, but outdoor exposure and weathering can shorten intervals. - Is a clear finish better than a tinted stain for brick?
Clear finishes preserve natural brick texture, while tinted stains can enhance color but may alter texture visibility. Choose based on desired appearance and protection level.