- You should allow yourself time to do the job properly rather than rushing when laying concrete.
- However, you must go straight to work when the concrete is mixed, have plenty of help according to the size of the job or pour in stages.
- You should level or screed the concrete as soon as possible otherwise, if allowed to set it will require much more effort to get leveled. (concrete is a heavy material to work with and should it be allowed to set, well that could ruin the look of the job and as well cause other problems in the next stage of the project).
- To permit slow drying you can wet the concrete down with water and place black plastic sheeting over the new poured area or keep the area damp with a water hose. (black plastic sheeting is available at most home improvement stores)
- Before driving on newly poured concrete allow several days depending on weather conditions. Also be mindful of the weight of the vehicle, large or heavier sized vehicles may require a longer hardening period.
- If replacing small sections of concrete you may wish to increase the area of the repair, smaller sections may depress easily. Compact and thicken areas to be repaired if possible. Concrete cracks for a reason, try and find out why and repair the problem area.
- The majority of repairs can be completed right, if you do a little home work and plan ahead!
Calculating volume of ready-mixed concrete required for your project:
- As a guide, multiply length x width x depth of the space you need to fill. This will calculate a cubic size, or volume, of concrete required (see calculator).
- Note: you may also need to consider additional features of the job e.g. slope, drainage, accessibility etc.
- Make sure you measure the depth of the area in several places and average the measurements. It can not be stressed enough that proper ground base preparation is a key to consideration when placing new concrete, proper compaction, removal of all large roots, grass and other foreign materials are essential before pouring concrete! Never pour over grass as grass, mulch, leaves, ect… are organic materials and will deteriorate leaving your new concrete without a proper base which effects the long term performance of your new concrete. If your doing it yourself or having a contractor do it for you proper prep is key to a long lasting and attractive job.
Health and safety: Suitable clothing including impervious gloves, long sleeves, eye protection and boots should always be worn when handling concrete.
- soil compactor
- Concrete pull
- screed boards
- strong wheelbarrow or wheel barrows
- proper finishing broom
- sod cutter
- bull and hand floats
- Ready-mixed concrete
- Form Boards
- Expansion joint material
Preparing the ground or base: The preparation is dependent upon the existing surface and the concrete application. Measure and mark out the area you need to concrete, using a string line and wooden pegs, ensuring that the corners have a 90 degree angle. The ground should be leveled and well compacted with a compactor to provide a base for your concrete.
Assembling your form work: The form work is made up of timber planks 3/4″ to 1.5” thick that go around the edge of the area you want to concrete. This will support the concrete as it hardens and also is used to form a level for the concrete, make sure to use plenty of stakes to keep the boards from bowing out (cut or drive stakes to a level or level height of the form boards so that they do not interfere with the board that will be used to screed the concrete level) . Check the forms for level and proper fall as needed. (Make sure to provide for control joints during the site preparation stage of the project)
Sub-base should be well compacted and check for proper depth in several places, remove or add material as needed. Take calculated average depth and figure the amount of concrete that will be needed. (use the calculator on this web site if needed) It is always a good idea to order over the estimated amount of concrete by 5 to 10% to ensure that you have a bit more than needed to complete the job as you don’t want to run short by a wheel barrel or bucket full. Most experienced concrete contractors always do this when ordering their ready mix concrete.
Pouring the concrete into your area: Make sure not to over wet the concrete being poured, it may make it easier to work but also weakens the end product. Cement to water ration is very important. Adding to much water to the concrete will void the concrete companies stated psi rating. Concrete professional understand this and only add water to bring the concrete to the proper slump if the truck arrives with to low of a slump. (less than stated on the order) If pouring concrete from a barrel truck it is importation to get the concrete placed as quickly as possible as the work ability and ultimate strength of the concrete is time driven.
Spread the concrete between the forms as close to level with the form boards using a concrete pull or other leveling tool, Tap the sides of the forms lightly to fill in any voids. Using a piece of wood with a good straight edge 6″ to 12″s longer than your form, place one person at each end, level the concrete use a sawing motion across the surface of the concrete whilst moving forward slowly, this should be done at least twice. Ensure that the concrete gets into the corners of your forms and that there are no low spots. If there low spots, fill them in and repeat the screed process.
Finishing the surface: Depending upon the use there are a number of options for finishing the surface of the concrete. To achieve a smooth surface use bull float and hand trowels to a smooth finish on the concrete. After that concrete has been smoothed out use the edging tool to finish the edges and then use the hand trowel to once again smooth the top of the concrete where the edger was used. Allow the concrete to dry to the point that there is a slight resistance to finger pressure. Once the concrete is firm lightly pull the broom accorss the concrete to give a light broom texture. The broom should create a light brushed effect which indents the surface without pulling it apart. (this does not need to be perfect)
When working with concrete it is important to be patient, especially when working with a small new concrete area.
Let the concrete set: Cover the concrete with black plastic sheeting weighted down at the edges to prevent it from drying out too quickly or keep it damp for several days if possible. *Usually keeping properly prepared concrete damp for the first 12 to 24 hours will do the job. Light foot traffic is usually okay after 12 hours or so and light automobile traffic needs to wait at least 3-5 days depending on weather and other conditions.
Remember to plan for proper expansion and control joints. Expansion joints are between two pieces of concrete that will provide a complete separation of the concrete areas. Control joints are either hand tooled or saw cut into the concrete, saw cutting control joints needs to be completed in most cases with 12-24 hours of finishing the concrete.
Keep in mind that the information provided here are general guide lines and your concrete contractor or other source, if you are doing the job yourself should be consulted if you are new to pouring concrete, all jobs are not the same and should not be treated that way.
Weather: Concrete should not be laid in very cold weather or in rainy conditions.
When it’s hot outside, the earlier you start pouring concrete the better!
Good luck and remember to plan, plan, plan. Good planning will ensure that you get the best results.