Exterior Finishes
When applying sealer to exterior concrete, it is important to take into consideration the traffic it will handle as well as the slope and exposure to water it will receive. With these aspects in mind, you can decide on the system that will best suit your slab as well as looking great.
Concrete Sealing Completed by Reems Concrete Concepts.
Concrete Sealing/Resealing
Weather its new or old concrete it is important to use some kind of sealer to protect the concrete from the ingress of stains. There are two main kinds of sealers used on concrete; penetrating sealers and topical sealers. Penetrating sealers will create a hydrophobic barrier in the pores of the concrete preventing the ingress of water and stains. As the water is unable to penetrate into the pores of the concrete, mold is unable to grow. Penetrating sealers will also not affect the appearance of the concrete in anyway.
Topical Sealers (commonly known as single pack acrylic) work by forming a thin film of acrylic resin on top of the concrete surface. This film acts as a barrier to stop the ingress of water and stain and stops the growth of mold. Topical sealers will increase the slip factor of the floor so it is important to use have a suitable texture in the concrete or use slip reduction particles in the coating. Topical sealer are available in full depth color or clear. Clear topical sealers will slightly darken the concrete to a wet look appearance and can come in gloss or matte.
Exposed Aggregate Sealing/Resealing
Sealing exposed aggregate typically involves a clear topical sealer. This sealer prevents water from penetrating into the pores of the concrete and stops mold from growing. The sealer also prevents staining from leaves and other sources as well as providing a glossy finish.
Another option is to use a penetrating sealer which will not alter the sheen of the concrete whilst stopping the penetration of water. Penetrating sealers are also used in situation in which the incline of the slope could lead to slipping. By not forming a film of resin on top of the concrete, the slip factor is minimized.
Cementitious Spray Finish
Cementitious Spray Finish otherwise known as Spray-Crete is a great system the provides long term durability with a wide range of texture and finishes. If your slab is looking old with divot and chips missing Cementitious Spray Finish may be a good option for you. This system allows for a high film build which will fill and cover all of the superficial imperfections. Cementitious Spray Finish also provides a variable non slip finish which can be built up to achieve quite significant results.
With a huge range of different styles (Blanket Fleck, Stencil, Tiles, Sandstone, to name a few) it is extremely versatile and can completely rejuvenate an entertaining area or drive way.
Hone & Seal
A Hone & Seal finish is simply a concrete slab cut and ground to expose as little or as much stone as desired, and then sealed with a topical sealer. It can look very similar to polished concrete and in some circumstance be the preferable system. If the slab is exposed to the weather or around a pool this system may be preferable as a non slip particle can be added to prevent slipping.
The type of sealer can vary from single pack solvent based through the two pack polyurethanes. It is important to think about long term protection and re-coat periods when choosing the sealer for your floor. A two pack polyurethane is a far superior product compared to a single pack solvent based sealer. There can be significant price difference, However you can expect 3-4 times the life span from the two pack poly urethane.
Overcrete Resurfacing System Completed by Floor Illusions.
Pool Surrounds
It is imperative that a finish around a pool provides sufficient non slip resistance as well as being able to handle pooling water. Single pack solvent based sealers, two pack urethanes and cementious spray finish can all be suitable around a pool with a textured finish. Water based sealers may not be the best fit for this application as the pooling water can re-emulsify or soften the coating (not all water based sealers will do this).
Natural Stone
Natural stone can be difficult to seal as there are a wide range if different types of stone with varying finishes. A good test when looking to seal natural stone is to check its porosity. Overly porous stone (sandstone) can be sealed with topical or film forming sealers as the sealer will be able to penetrate into the stone and achieve a mechanical key. Non porous stone (granite, marble etc) requires a solvent based penetrating sealer to prevent the ingress of stains and water. A water based penetrating sealer may suffice although solvent based penetrating sealers have a smaller molecule which allows them to penetrate and adhere better.