Masonry stain works the same way wood stain does; by penetrating the surface of the brick, concrete, or stucco, and depositing pigment. Stain can be used to create a unique look; brick stain can be used to match new masonry to old- for example, on a new addition.
Penetrating masonry stains are superior to paint in several ways. Because they soak into the surface, instead of sitting on top, they won’t bubble or peel. They won’t obscure the natural texture of the brick, stucco, or stone. They also provide some degree of protection from the weather, preventing fading and erosion while allowing water vapor to move through the wall without causing damage. Furthermore, stains provide a barrier against airborne chemicals including acid rain.
Acrylic (Water-based) Stains
Acrylic stains are more environmentally friendly than their solvent-based counterparts and clean up with water. Because they contain few or no VOCs (volatile organic compounds), they are the best choice when working in poorly ventilated areas, or if allergies or chemical sensitivities are a concern.
Solvent-based stains provide a more water-resistant seal than do acrylics. They are stronger smelling and cleanup requires the use of mineral spirits or another solvent.
Both acrylic and solvent-based stains are fairly easy to apply, and should yield similar results as long as the surface is prepared correctly.
What to Look For
Natural pigments fade less quickly than do synthetic ones. Look for a UV-resistant product if the stain will be used outdoors in a sunny area. This will reduce the need for frequent touch-ups.
Stains that contain silicone are incompatible with many other products. Use them only on previously unfinished surfaces, unless the label specifies otherwise.
Read the label to determine how moisture-resistant each product is. On an exterior wall, it’s important for water vapors to be able to move through the masonry. In the winter, humid interior air will dry to travel outdoors, where it’s typically drier. If the barrier to the outside is completely waterproof, condensation between the masonry and the sealer can cause the stucco or brick to deteriorate.
Indoors (in a damp basement for example), a watertight surface is necessary to avoid damaged possessions and mildew problems. Moisture from the damp soil will move toward the drier indoor space, creating condensation. Choose a combination waterproofer/stain, or seal the surface with a separate waterproofing medium before staining.
The label will also say which surfaces the stain can be used on. Most are formulated for use on horizontal surfaces. For walls, look for “for use on vertical surfaces” on the label.
What to Expect from a Masonry Stain
Stains don’t have the covering power paints do. Damaged or discolored surfaces can’t be covered up with stain. There will also be some variation in color, depending on the surface texture and the original color of the material being stained. Stained surfaces look much more organic and natural than painted ones.
Stained surfaces also require a fair amount of maintenance. In an area that receives equal amounts of sun and shade, your project will probably need restaining every five years or so. Masonry exposed to direct sunlight most of the time will fade faster, although using a high quality, UV resistant stain can help prevent this to some extent.
Masonry stains are an easy, effective, and relatively cheap way to beautify paths, patios, and retaining walls. If your budget doesn’t allow a complete revamp, you can still freshen up the space with a coat of stain.