Installing a durable concrete sidewalk or patio requires some basic components in our area of the country since Chester County is subject to freeze/thaw conditions.
First, whether the concrete sidewalk is new or a replacement, the soil under the area should be well compacted. Settlement of soil or fill is the leading cause of cracked concrete.
Second, a minimum four inch stone base should be installed to give the new concrete a cushion and to allow for water drainage.
Third, walkways and patios should not be poured in long, uninterrupted stretches. Two kinds of "lines" or joints are used to give a walkway the final appearance of having many "blocks" - control joints and expansion joints. They are not the same thing and are used for different purposes.
Expansion joints are placed about every 12 to 16 feet. Expansion joints are usually narrow (1/2 " wide) strips of white PVC, rigid foam, or rubber that divide the walk or patio into sections.
Control joints are more common and are placed about every three feet. They are the majority of the "lines" you see in a concrete walkway that makes a walkway look like "blocks". These control lines are scored with a tool when the concrete is still wet. They are called control joints because they "control" cracking. Whenever concrete is poured in a long and narrow section like a walkway, the concrete has a tendency to want to crack. By scoring control lines, any cracks that might develop in the future will develop down in the scored line and will remain unseen. This is how you prevent unsightly zig-zag looking cracks that spoil the clean look of a walkway.
Another way to prevent and control cracking is by reinforcing concrete with wire mesh or fiber mesh. The use of steel rods or bars (re-bar) is not common in walkways and is usually reserved for walls and structural concrete. We normally use steel wire mesh to reinforce concrete.
Lastly, the quality of concrete used in a walkway affects its performance and durability. We use only 3500 PSI or 4000 PSI concrete which must be specified to our concrete supplier who delivers the concrete in their cement mixers. PSI stands for "pounds per square inch" and is a measure of how much force is needed to break the concrete when it is fully cured or dried - essentially a measure of strength.
The quality of concrete is very much affected by how much water is used in the mix. Very "soupy" or wet concrete is easy to pour but it will not be strong or durable. It takes more effort to pour stiffer concrete but the result is superior. It's also important to wait until all surface water has evaporated from the concrete surface before giving it the final finish. This is critical to having a durable surface that will not flake away over time.
These are the basics. Countless other things affect the quality, beauty, and durability of a new concrete patio or sidewalk, which is why hiring a conscientious contractor with many years of experience can result in a great job. We've been in business since 1978 and we bring a wealth of knowledge and experience to our work. Please call or send us an e-mail if you'd like an estimate on installing a beautiful, high quality concrete walkway.
PA Registration # - PA044324