Lime Wash & Mineral Paints for Brick: Romabio vs Keim
Painted brick has become increasingly popular in East Tennessee, but traditional exterior paint is not always the best choice for masonry. Lime wash and mineral paints offer a breathable, natural alternative that lets moisture escape while transforming your brick's appearance. After working with both Romabio and Keim products on homes throughout the Tri-Cities, here is what I have learned about each.
Why Mineral-Based Products for Brick?
Brick is porous. It absorbs and releases moisture constantly. When you seal brick with traditional acrylic or latex paint, you trap that moisture inside the masonry. Over time, this can cause paint peeling, efflorescence, and in severe cases, damage to the brick itself.
Lime wash and mineral paints are vapor-permeable. They allow the brick to breathe while still providing color and protection. Instead of sitting on the surface like plastic film, they bond chemically with the masite to become part of the masonry.
Additional Benefits
- Natural appearance. These products create a soft, aged look rather than the flat-plastic appearance of painted brick.
- UV stable. Mineral-based colors do not fade like organic pigments in standard paints.
- Mold resistant. The high pH and mineral composition naturally resists mold and mildew growth.
- Maintenance friendly. Many can be touched up or refreshed without the peeling and scraping required with film-forming paints.
Romabio: The Popular Choice
Romabio has gained significant popularity in recent years, partly through strong social media presence and contractor marketing. They offer two main products for brick: Masonry Flat and Classico Limewash.
Romabio Masonry Flat
This is a mineral-based paint rather than a true lime wash. It provides more consistent coverage and a more uniform appearance than lime wash, while still allowing the brick to breathe. For homeowners who want a clean, even look, Masonry Flat is often the better choice.
- Covers more evenly than lime wash
- Available in a good range of colors
- Can be applied by brush, roller, or spray
- Still breathable, though less so than pure lime wash
Romabio Classico Limewash
True lime wash creates a weathered, European aesthetic with visible variation and texture. It is not for everyone, but for the right home, the effect is stunning. The product goes on thin and builds up over multiple coats.
- Creates authentic aged appearance
- Fully breathable mineral composition
- Can be applied at different concentrations for varied effects
- Requires learning proper technique
Romabio Learning Curve
Both Romabio products require adjustment if you are coming from conventional painting. They apply and behave differently than acrylic paints. The company provides training and application guides, and following these is important for good results.
Common issues include applying too thickly, not dampening the surface properly, and incorrect expectations about the final appearance. The characteristic variation of lime wash is a feature, not a flaw, but homeowners need to understand this before the project begins.
Keim Mineral Paints: The European Standard
Keim is a German company with over 140 years of experience in mineral paints. Their products are used on historic buildings throughout Europe and are considered the gold standard for breathable masonry coatings. They also offer limewash products for a more traditional aesthetic.
Keim Advantages
- Easier application. Keim products apply more like conventional paint, making them more forgiving for painters transitioning from traditional products.
- Consistent coverage. The finish is more uniform than lime wash while maintaining full breathability.
- Proven longevity. Buildings painted with Keim in the 1800s still look good. The track record is unmatched.
- Technical support. Keim provides excellent technical guidance for contractors.
Keim Considerations
- Higher cost. Keim products are more expensive than Romabio and significantly more than conventional paint.
- Limited distribution. Finding Keim products requires more effort than picking up paint at the local store.
- Surface preparation. Like all mineral paints, proper surface prep is critical for adhesion.
Comparison: Which Should You Choose?
| Factor | Romabio | Keim |
|---|---|---|
| Ease of Application | Learning curve required | More like conventional paint |
| Finish Appearance | More variation (especially limewash) | More consistent |
| Availability | Easier to obtain | Specialty distribution |
| Price Point | Premium | Higher premium |
| Track Record | Good (newer company) | Exceptional (140+ years) |
| Best For | Limewash aesthetic, budget conscious | Historic buildings, maximum durability |
Our Recommendation
For most residential brick painting in the Tri-Cities, we typically work with Romabio Masonry Flat. It balances breathability, appearance, and cost effectively. For clients who specifically want the aged limewash look, Romabio Classico delivers that aesthetic.
For historic properties or clients who prioritize maximum longevity and are willing to invest accordingly, Keim is the superior choice. The initial cost is higher, but the product may never need replacement.
Application Process
Regardless of product choice, proper application of mineral paints requires specific steps:
- Surface preparation. Remove loose material, efflorescence, mold, and dirt. Power washing is typically necessary, followed by sufficient drying time.
- Repair masonry defects. Cracks, damaged mortar, and failed areas must be addressed before painting. We use appropriate mineral-based repair products.
- Dampen the surface. Most mineral paints require a damp (not wet) substrate for proper absorption and bonding.
- Apply thin coats. Multiple thin applications outperform single thick coats. This allows proper carbonation and curing.
- Respect cure times. These products cure through chemical reaction with air. Proper time between coats is essential.
Is Mineral Paint Right for Your Home?
Mineral paints and lime wash are excellent for brick that is currently unpainted or has only previous mineral coatings. If your brick has already been painted with conventional latex or acrylic, the situation is more complex. The existing paint creates a barrier that prevents proper bonding.
During our free estimate process, we evaluate your brick's current condition, any existing coatings, and discuss your aesthetic goals. Sometimes mineral paint is the clear answer. Sometimes conventional exterior paint makes more sense. We provide honest recommendations based on what will work best for your specific situation.
With 250+ projects completed in the Tri-Cities, we have the experience to guide you through these decisions. If you are considering painting your brick, we would be happy to discuss options.