How Much is Too Much? To Smooth or Not: a blog covering concrete sealing options and what you need to know before undertaking the job.

I’m sure you’ve seen it. That unsightly, white-ish, rough, and often cracking concrete surface that appears on sidewalks and driveways. It’s more than an eyesore; it’s a hazard to yourself and others around you. The rough surface can cause tripping; the cracking can lead to falling and serious injury. Don’t let these two enemies take over your home – especially if you have children. In this post, I’ll cover some of the options available for remedying these problems.

“How much is too much? To smooth or not to smooth?”

This was the question on my mind when I undertook the task of smoothing out the exterior concrete of my home. You see, my house is old (built in the ’50s), and it has suffered from water intrusion. The result is that the concrete foundation, particularly around windows and doors, has gotten pretty rough.

I’ve been told by several masons that I can apply cement over the existing concrete to provide a smoother surface. They say this will also help seal and protect the foundation against future water damage. But I have also heard that applying too much cement can trap moisture, which might cause even more damage to my home’s foundation. So how much cement is too much?

Cement sealers are a great way to improve the look and longevity of your concrete. But how much is too much? We’ve all seen that house with the driveway that looks like glass. It’s shiny, smooth and slippery when wet. While this probably makes for the easiest cleanup job ever (just wipe it off with a towel) it’s not really what you want for your sidewalk or driveway.

It’s kind of like putting a high gloss polyurethane finish on your wood flooring: nice for tables, but not safe for walking on. A good rule of thumb is to apply no more than 2 coats unless you want something that looks like glass.

One more thing to think about, too many applications of sealer can actually cause damage to your concrete by trapping moisture. This can lead to cracks and other problems.

To smooth or not to smooth, that is a question that concrete professionals and their clients ask themselves every single day. While a smooth concrete surface is usually desired when it comes to concrete installations, there are instances where the rougher the better is preferred. That’s why we now have post-tensioned concrete.

Post-tensioning is a method of reinforcing (strengthening) concrete or other materials with high-strength steel strands or bars, typically referred to as tendons. In post-tensioned concrete construction, the tendons are tensioned after the surrounding concrete structure has been cast and is in compression. The tendons are not placed in contact with the concrete; rather, they are placed within a protective sleeve or duct which is then embedded in the concrete prior to pouring. Post-tensioning tendons are most commonly made from plain high-tensile steel bars, isolated or encased in protective plastic (polyethylene) sheathing; but can also be made from uncoated high-strength steel wire (7 wire strands), fiber reinforced polymer tendons or even stainless steel.

The answer is not as simple as it might seem. If a concrete slab is sealed, there are several benefits including protection from moisture and stains, a reduction in dusting and an improvement of the appearance of the concrete. While all of these benefits are important, some homeowners want to seal their concrete for reasons that may not be worth the worry. The main reason for sealing is to reduce dusting and improve the look of the concrete floor. Sealing does not make concrete stronger, but it does help prevent damage from abrasion or staining. When a sealer is applied to concrete, it fills in minute pores, giving the surface a uniform appearance and color.

For decades, contractors have been sealing outdoor concrete slabs to protect them from moisture and freeze/thaw damage. Originally sodium silicate was used as a sealer. In time, we found that sodium silicate did not perform well on outdoor concrete because water could penetrate through cracks in the concrete and still eventually get into the interior of the slab. This led to lots of disappointments with sealers. Over time we have developed better products that can seal even very porous concretes from moisture penetration. The most effective products are penetrating densifiers that are mixed with water before application by spraying or rolling them

A concrete sealer is a protective coating applied to concrete surfaces to protect it from elements such as water, acid, alkalis and salt. They also impart stain-resistance properties and increase the strength of concrete. There are two types of sealers: film forming and penetrating.

Film formers are applied as a thin layer on the surface whereas penetrating sealers penetrate into the concrete. The latter is more durable than the former. A combination of both is more effective in protecting your concrete surfaces.

There are two types of sealing products available in the market: solvent based and water based sealers. Water based sealers are eco-friendly but are not as durable or long lasting as solvent based ones.

Sealers may be applied to both exterior and interior surfaces, however, different formulations may be required for each.

Many people use a sealer to enhance the appearance of their floor but this is not always a good idea as some products may darken your floor and make it look uneven.

What about the sealer? Concrete sealers are used for many reasons. Some sealers are used to enhance the appearance of a surface, others are protective and provide a barrier between the concrete and outside contaminants. When purchasing a sealer, it is important to know what you need it to do. Some sealers will actually darken the color of the concrete, while others provide a glossy or matte finish. Some sealers penetrate into the concrete surface, some form a film on top of the surface and some do both. When choosing a sealer it is important to know if you want to protect against efflorescence, staining, dirt and dusting and also what look/sheen you desire for your project.

Below are some common types of concrete sealers:

Acrylics

Acrylics are easy to apply and maintain, they have low odor levels, they resist stains better than other finishes and they can be cleaned using mild detergents. Acrylic sealants do not react with cement compounds so they never lose their bond. They last approximately one year before needing a reapplication.

Epoxies

Epoxies are harder than acrylics but they must be mixed properly or they can turn yellow over time. They have low odor