Constructing a concrete walkway does not take a lot of skill as long as you understand a few important facts. The concrete needs to be poured so that it will cause water to flow away from foundations and other places where it may tend to form pools. You also need to put some type of wire into the concrete to make it stronger and more durable. Concrete needs room to expand and contract. So, sidewalks need to take this into consideration. Finally, it is a good idea to lay the concrete onto a stable base of sand or gravel. Remembering these facts should get you moving on that walkway project.
Make sure that you know where you want the sidewalk and how wide it should be.
The first thing is to decide what you are connecting with the sidewalk. Does it go from your front door to the sidewalk at the street? Will it connect your house to your garage? Once you know where the walkway will go, you have to determine how much traffic it will need to effectively carry. If this is a walk from your door to the mailbox that will carry one person each direction once per day, you will not need the same type of walkway that a store or church might need to bring in crowds several times per week.
The use of the walk will determine its width.
If a walkway only needs to carry a couple of people at a time, it probably will do just fine with a width of 42 or 48 inches. If people will congregate on the walkway or it will carry large numbers of people from time to time, you may need to widen it by 2 feet or more. It is a good idea to go someplace where a walkway is already being used to handle your size need and measure it. You may want to ask the owners how that size walk is working for them and adjust accordingly.
Once you know the placement, length, and width of the walkway, you need to decide on its shape.
Most walkways are just straight lines. This is a great functional way to construct a sidewalk. For the amatuer, it is probably the best way to build it because it takes less skill than trying to concoct fancy shapes. If you are adventurous and willing to take a risk or two, you can devise just about any style walkway.
The next minor choice that you have to make is whether the walk will be raised or not.
Some walkways are made to be level with the surrounding yard. Others are raised a few inches above it to make them seem more prominent. Both have advantages and disadvantages. The choice is yours because it does not significantly change the difficulty of the project either way.
Remove the sod or dig out the dirt to the level of the base of the walkway.
If you are making a sidewalk level to the ground, you will need to remove the soil to about twice the depth needed for the thickness of concrete that you intend to pour. Most sidewalks are about 4 inches thick although some commercial walkways may be as much as 8 inches thick. For raised sidewalks, dig out about the same amount as the thickness of the walkway. Either way, you need to go about 4 or 5 inches wider than the the width of the sidewalk to allow room for forms.
It is a good plan to have another small project needing concrete available to use up extra product when you order it.
Walkways tend to use less concrete than the minimum order for most ready mix companies. When computing your needs for concrete, multiply the width times the length times the thickness to get the cubic feet. Remember to convert the inches to fractions of a foot to get the right number. A cubic yard of concrete is 27 cubic feet. So, if your sidewalk is 30 feet long, 4 feet wide, and 4 inches deep, you will multiply 30 x 4 x 1/3 = 40 cubic feet or about 1 and 1/2 cubic yards. If you have to order 2 yards for a minimum, you have enough concrete to make a small patio or a foundation for a child’s playhouse. You will have to be prepared for this before the truck arrives. You can always pay for the extra and let the driver waste it someplace else.
Order about the same amount of gravel as concrete.
Because dump trucks tend to bring huge amounts of gravel at one time, you may want to see if your neighbors would like to split a load. The other option is to use a pickup to go get the gravel yourself. You will be shoveling it around anyway at some point. Fill the walkway area with about 3 to 4 inches of gravel. This is an imprecise operation so do not obsess about being exactly to the inch in all places. Just get close.
Install your forms on each side of the walk and on top of the gravel if possible.
Use stakes on the outside of the forms to hold them in place and to brace them. Concrete is heavy. Without bracing, your forms may bend or shift and distort your walkway. Use one inch lumber to make joints in the sidewalk. Using treated lumber for this is a good plan because these pieces will remain in the sidewalk. If you do not make joints, you will need to create some crack joints along the length of the walkway after the pour.
Lay metal into the sidewalk area between the forms.
Use some woven wire fencing for the metal in your sidewalk or buy some metal grid work designed for this purpose. If you use wood to separate your joints, drill a couple of holes in each piece and thread some wire through it to link your joints together. These pieces should extend about 6 to 10 inches on either side of the joint.
Once the gravel and metal are in place, it is time to pour concrete.
You will need a board about a foot or two longer than the sidewalk is wide. A good straight piece of 2×4 will work to strike off the concrete after the pour. In cold weather, have the ready mix place add a drying agent to the concrete to help it harden faster. This makes the product slightly weaker, but for a sidewalk it should not hurt. In hot weather, do not let the driver dump the concrete if it is too dry. Make the driver add water from the tank on the truck and mix the concrete a little more. Fill the forms until they are almost too full. Concrete shrinks a little and you will need this amount. As each joint is filled, pull up on the wire to bring it more into the center of the concrete. Do not let it protrude out of the top surface of the walkway.
Begin the finish process as soon as the pouring ends.
Using the 2×4, get a friend and use it like a crosscut saw back and forth along the surface of the concrete. Use the forms to keep it steady and level. Work your way slowly along the length of the walkway until the entire walkway has had the excess concrete removed. It will run down the outside of the forms. Do not be concerned, this is normal and is easy to deal with later.
Use a float to bring the water to the surface of the concrete.
Drag the float over the surface of the walkway with a little up and down movement until the entire surface has a nice watery finish showing. You will have about 30 minutes to an hour to complete this operation if it is not too hot. Once the surface looks uniform, let the concrete set for a few minutes.
When most of the water is starting to dry out, start putting your final finish on the concrete walkway.
Use a push broom and drag it carefully across the walkway to put a textured surface in place to make it safer to walk on. Use an edging tool to make the shape edge that you want. Use the same tool at the joints. If you did not put in wooden joints, use the tool to make nice straight paths about 1/2 inch deep across the walkway about every 6 to 8 feet. Let the concrete dry about 24 or 36 hours and remove the forms. Do any fill work along the edges. For light traffic, the walkway should be ready to use. For heavy traffic or objects, wait about 3 to 5 days for the concrete to fully cure.
