It seems like something as tough as your concrete or asphalt driveway would be able to easily stand up to something as small as a drop of water. But the effects of rain and snow, especially if that moisture gets into cracks in the surface and then freezes, can do a surprising amount of damage to a driveway, walkway, wall, or other concrete, masonry or asphalt surface.
So, before winter hits again this year, fight back by sealing those porous surfaces against water intrusion. There are a number of sealers that are formulated specifically for this purpose, and they are easy to apply without special equipment.
CONCRETE AND MASONRY SEALERS
For a tough finish on concrete, you’ll want to use a specific concrete sealer. Not intended for brick, block, stone and other masonry, concrete waterproofing sealers penetrate deep into the surface of the concrete — up to one inch of penetration on previously unsealed concrete — and forms a very tough barrier against moisture.
Some sealers are formulated for specific applications. If you have a concrete slab, for example, that is subject to a lot of grease and oil on a regular basis, selecting a sealer that is specifically made for that will greatly simplify your cleaning. There are also sealers formulated for underwater concrete, such as ponds and pools, for sanitary surfaces, and other applications.
For most masonry surfaces — brick, stone or ceramic tile — a masonry sealer is the proper choice. Depending on the type of masonry sealer, some will also work to seal concrete slabs. Masonry sealers will penetrate into the pores in the surface of the masonry and seal them against moisture. The sealer also helps to protect against buildups of dirt, oil, grease and markings from automobile tires. Masonry sealers are not intended for use on asphalt, glazed ceramic tile or on wooden surfaces.
Sealers also come in different surface “sheens,” depending on the look you want. While all of them are clear, some types dry to a completely flat sheen and leave the surface looking unsealed. Other types dry to a glossy “wet” look, and the depth of the gloss increases with each application. There are also semi-gloss sheens that are in between flat and glossy. The choice of how glossy you want the finished surface is typically one of personal preference; however, with some types of sealers the glossier the product is the more abrasion-resistant properties it has.
APPLYING CONCRETE AND MASONRY SEALERS
As with the application of most coatings, you need to start with a surface that is clean and dry. That may be as simple as a good sweeping or blowing off of the surface with a leaf blower, or it may involve pressure washing or spot scrubbing to clean off heavily soiled areas. If you do end up having to use water or other liquid cleaners, be sure that the surface is allowed to dry completely before applying the sealers — application over a wet surface will almost guarantee that the sealer will fail.
If efflorescence is visible — a chalky white coating on the masonry or concrete that occurs as salts leach out of the cement during drying — that needs to be removed as well. You can clean efflorescence with a diluted mixture of muriatic acid, but most sealers require that the acid then be neutralized — a 50/50 mixture of water and ammonia is a common neutralizer.
The sealer can usually be applied using a brush, roller or spray. Pump-up garden sprayers work well for some types of sealers, as do some types of paint sprayers. Some sealers are formulated for a single-coat application, and others require a buildup of multiple coats.
Like concrete and masonry, asphalt is also subject to the effects of wear and tear as well as the detrimental effect of heat, rainwater and freeze/thaw cycles. Left alone, the asphalt will begin to deteriorate over time, and the periodic application of an asphalt sealer will help prevent the much more expensive alternative of having to remove and replace the asphalt completely if it begins to break down.
You can apply asphalt sealers yourself if desired. Large cracks need to be patched first, using a cold-application asphalt mix or an asphalt crack sealer. After that, the surface needs to be cleaned, and then allowed to dry if necessary. Depending on the size of the area, the sealer can then be applied using a special mop, a rough-surface roller, or an asphalt brush.
For this project, you might also want to consider having the work done by a company that specializes in asphalt sealing. Get two bids from reputable, licensed, local companies, and remember that the low bid is not necessarily the best bid. The bids should include patching any large cracks, as well as a complete cleaning of the asphalt prior to application of the sealer.
Sealers are available at some home centers and hardware stores, but your best bet for expert advice and a wide selection of products is to check with a store that specializes in masonry or asphalt products. Each product will have specific uses, application methods, weather and temperature application restrictions, and safety precautions, so be sure you carefully read and follow ALL of the manufacturer’s specific recommendations.
Remodeling and repair questions? E-mail Paul at firstname.lastname@example.org.