Step 1: Planning Introduction
Thinking of doing concrete restorations or new projects yourself? If you feel that you have the competences and want to give it a shot, you can save good money. Sums that intermediaries would put in their pockets and you will have a great feeling of achievement from it, even if that implies physical effort. A concrete project requires planning and preparation for the impending concrete delivery.
At Bétonmobile.com, we are proud of being able to say that we are one of the exceptional concrete delivery companies that provides assistance and continued support to its customers. This guide combined with the multiple services that we offer along with our technicians by telephone, will enable you to theoretically bridge the various stages to successfully complete your concrete project. Please note that this is not a complete guide, it is intended as a basic guide in order to clarify and better understand the various stages. For more details, don’t hesitate to contact: American Concrete Institute or the Quebec Building Code.
It is very important to carefully plan a concrete casting project. When unplanned, certain types of projects can be redone without great costs, not the case however for concrete. Being a heavy material, difficult to move and with limited drying time once the dumping has started, it is very costly to have to restart a project. Concrete finishing is a profession by itself; hence, certain jobs require a professional while others you can perform yourself. Nevertheless, it’s always a good idea to inquire beforehand for ideas on how to proceed. We will attempt explaining these procedures further on in this guide but nothing prevents you from viewing videos on sites such as YouTube. Don’t forget to contact your municipality or borough to inquire about bylaws and regulations concerning concrete deliveries (construction, parking permits…). Any infractions to parking and trespassing etc… bylaws will be added to your invoice. It is therefore important to anticipate such items!
For an estimate or price, it is important that you give us your dimensions. As mentioned, concrete is heavy and exerts a lot of pressure especially on vertical projects such as foundation walls. We will return to forms later, as for dimensions however, it is important to realise that this lateral pressure can cause the formwork to balloon or split them open. Dimensions are as important with ground level and horizontal jobs such as patio pads or basement floors. The problem is not if you have 20’ X 10’; it is easy to calculate that you have 200 square feet. Even if a little off due to uneven contours, it’s not where the problem lies. People have a tendency to measure depth at one place only thinking the ground is levelled everywhere. You will probably be surprised by doing so. If your measurements are taken to thin, you will have too much concrete at certain places resulting in a higher quantity than on the estimate. Should you take a measure at the highest part, it may have for effect that the thickness will be so thin at some places that we won’t be able to pour concrete. It is therefore important to measure logically.
Your measures will also help you determine the wood needed for your forms if necessary. Don’t forget to buy more than needed. We will come back to this but it is always better to have a little more than not enough.
The materials mostly used, are 2×4, 2×6, 2×8 and at times plywood sheets.
Here is a list of tools that may be handy for concrete projects:
Shovel rounded tip: For digging patio or spa pads for example
Shovel Straight edge: Very handy for cleaning up concrete spills
Basic construction tools: hammer, nails, saw… to put together the forms
Sledge or heavy hammer: For hammering larger spikes in the ground that may be needed to keep in place heavier formwork
A level and a roll of string: to draw lines and levelling
Construction grade wheelbarrow: Small ones most likely won’t carry or be strong enough requiring more trips which equals more time justifying the cost difference between them. (We will get back to basic waiting times later on)
Oil: For oiling the forms
Concrete vibrator: Ideal for foundation wall jobs and for hard to reach places. Ask one of our specialists for advice on their usage.
Trowel: Make sure you are equipped with a (Darby) long handled style trowel for big surfaces
Rake (garden style): The most useful tool for levelling concrete, better than a shovel. Leaf rakes are absolutely useless.
Most of these tools can be rented at tool rental centres or bought at your local renovation centres.
Next comes time to think about different services that you may need. To learn more, visit the services section. For example, have you given any thought where the cement truck will park: on the street, your lawn or driveway? Will you need a pump to bring the concrete to your work site or will you use wheelbarrows? These are some of the questions that need answering before proceeding.
Step 2 : Preparation
To simply vulgarise the definition of concrete; it’s harder and more resistant than stone and can match the shape you want it to be. Concrete can match the shape of the surface you will apply it on. People tend to think that concrete will stick like glue to other surfaces, which is false. Also, concrete is not indestructible and may crack even if it’s the best strength and quality. The major cause of cracking is ground movement. Even if it’s impossible to see with the naked eye, the ground moves a bit each year, especially during the freeze / thaw period that we experience during the spring in Quebec. During the thaw, water melted from snow infiltrates the ground and when the temperature drops below zero, the water will freeze and expand which makes the ground move. The cycle goes around when the temperature rises and drops. Concrete may be one of the most resistant materials on earth, this repetitive cycle will cause cracking. Some grounds will move more than others, so unless you are a geologist it is very hard, if not impossible to know which type you have.
Even if you are planning interior projects, it will benefit you to read this section even if it mostly applies for exterior ones. It is practically impossible to reduce ground movement to 0%; therefore, we must put all chances on our side to limit this. Here is how. It is an aggregate mix (0 – ¾) of large and small stones that once compacted will form a bed that will greatly reduce ground movement. The small stones when mixed with the larger ones will fill and greatly reduce the voids between them. At this stage you MUST NOT use clean crushed rock (the next step). As mentioned above, it is very important to compact this aggregate, if not done properly it won’t be very useful. The construction code suggests a thickness of 14 inches of compaction. If you chose to reduce its thickness, be aware that it should at least be thicker than that of the concrete slab.
This section is dedicated for interior projects. Why don’t we compact interior jobs such as basement or garage floors? The main reason is because these are below frost levels and therefore less chances of ground movement. Another reason is to avoid breaking plumbing usually found in these floors. It is here that some people choose to skip other preparation steps thinking it’s enough! If you want your work done state of the arts, proceed with the next steps. The next step is the drainage bed using clean or ¾ net aggregate. Why? Keep in mind that one meter of pored concrete contains between 150 and 200 litres of water. It is in fact a lot of water and why the ¾ aggregate is needed, to drain this water. Without the drainage bed, the water will look for another way to escape (called bleeding) and it’s from the surface that it will do so. Bleeding will always occur; we will come back to it at the concrete finishing stage. However, too much bleeding will spoil the quality of your work. If we pour concrete directly over the compacted bed without drainage, bleeding will increase drastically. A thickness of 2, 3 inches will suffice for the drainage, don’t try compacting it either, it does not compact anyway, besides, you don’t want that.
For basement or garage floors, should you want to insulate by laying a plastic or Styrofoam barrier; Plastic prevents humidity and radon, gases which more & more present in our homes as well as being noxious, while Styrofoam insulates.
These 2 products being beneficial to your projects can also bring problems. As previously explained, water must be able to drain from the concrete. Problem is that the vapour barrier and Styrofoam are both waterproof products blocking water from draining. Your drainage bed will become useless. The key is to add your plastic sheet and / or Styrofoam under your drainage bed so both materials can do their jobs efficiently. Note that insulation is useless for exterior projects such as patio, spa or shed pads.
It is now time for you to establish if you need reinforced cement or not in your project. There are two types of armature: the basic wire mesh which can be durable or rebar (steel rods). Rebar are usually used for project such as: walls, foundations, elevated balconies etc. Mesh is mostly used for basement, garage floors or patios, etc. The two main functions for reinforcing are: reduce contraction and prevent slab separations in the event of cracking / fissures.
Fissures will be your main concern. As explained previously, ground movement could crack your concrete to the point of splitting your slabs in pieces, unless reinforced with steel mesh. Like an insurance policy, reinforcing will not prevent fissures in your concrete; it will make it perform as intended however. If your aggregate base was properly compacted and don’t experience any ground movement, your concrete may never have any fissures or cracks. For peace of mind, a little planning and reinforcing will go a long way worry free. It is really not recommended to exclude rebar in walls or balconies or any other structural jobs.
It is also very important how the reinforcement is placed in projects such as ground level decks / pads. People have a tendency to sit it on the rock bed and pour the concrete over it, this is sad as it will not serve much purpose. In the case of a four inch thick slab, it is recommended to place the reinforcement in the center of it so at tow inches. Your wits will help you to find the best way to achieve this. The easiest way to do this is by placing “Steps” (a piece in the shape of a step) placed at even intervals throughout to support the mesh or rods. Once tied together, you should be able to walk on them without them touching the rock bed.
Formwork is simply something (wood, metal etc.) that will keep the concrete within during the drying process and until the concrete is set enough to keep its shape. Here again your wits will guide you in using the appropriate materials providing they are strong enough to hold and keep the concrete until dried. One must be vigilant, concrete is very heavy and must not be underestimated as it can split open or tear down some of the best forms if not properly secured. Wood 2×4, 2×6, 2×8 are most used products along with plywood for formwork.
Some people will skimp on wood in order to save a few bucks. A word of advice! Not a good idea. Again, as mentioned previously, concrete is very heavy therefore, forms need to be very strong. Many times we have witnessed forms falling apart or breaking due to weak construction. When this occurs, the spilled concrete will probably be to dry and hard to manage by the time the defective form is repaired, not to mention you will need to double your efforts trying to reinsert it in the form. This could turn out to be a very costly situation, just to save a few dollars in form materials you may have to buy more concrete, extra truck delivery, extra waiting time etc. Many hundreds of dollars added to your invoice. To facilitate time at finishing, if building a deck for example, make sure your form is straight and level. Do not forget it is also at this stage you give it the degree of slant needed for your purpose. Usually, 1/8 inch per linear foot is sufficient.
Step 3 : The pour
It is now time to order your concrete. Should you have questions, don’t hesitate to contact us; our technicians are always available to answer all your questions. Concrete delivery is not quite the same as ordering a pizza, you must plan in advance. You will probably want to have the delivery on a specific day and at the right time. To make sure you can have it when you want it, it is recommended that you place your order 2 or 3 days in advance. If you are unable to do it, you may of course place your order 1 day before or even the same day, but there will be fewer places available and you will have to choose on of them. Some people tend to order their concrete 2 days in advance because they will finish preparing for the pour in 2 days. If you respect your schedule, you are very good, but a lot of things may happen between the time you order and the time the truck will show up. It is a wise decision to only plan your delivery once the preparation is complete.
When choosing the time of the day you want your concrete, the sooner the better. Some customers need extra time to unload their concrete and this is hard to plan ahead in the schedule. We may also be there sooner than expected if the previous pour went well. You must keep in mind that you have to be ready when the truck arrives whatever the time we aimed for. When you plan your concrete in the morning, fewer customers will have taken their concrete before you during the day and the truck has more chances of being on time. The best is always to try to be the first in the morning because the truck is always on time. Also, the heat will be less of a problem. The direct sunlight exposure you gain by pouring during the day can hurt your concrete. The surface may dry faster than the concrete itself. You will also have more energy to work with the concrete and to help you if a problematic situation occurs during the pour. If you have obligations that require you to plan your delivery in the late afternoon, we can help you all day long, but you might want to know that we are also open on Saturday mornings with no extra fees.
Betonmobile.com is basically a concrete delivery company that uses mobile concrete mixers. Our specialty is to make the job easier for people that have never worked with concrete before or even people that don’t work regularly with concrete. To make the job easier, we have other services to help you: concrete pumping and concrete finishing. For formwork rental, because it is a type of job that requires more knowledge about concrete, please refer to the formwork section for more information.
As you might have seen in the videos section, a mobile concrete mixer has a way of mixing concrete of its own, but when talking about the aspect of dumping the concrete, it simply slides in chutes that have the same dimensions and reach as a normal mixer. So if the truck can unload the concrete where you want it with the chutes it carries (directly in the forms, wheelbarrow, etc.) you can’t have a better situation. On the other hand, have a look at these examples that may happen:
The truck has to back up on your lawn or other areas of your property and causes damage.
The truck gets stuck on your lawn and needs towing at your expense.
The back alley is too narrow or the turn for the second back alley is too tight for the truck.
Tree branches that can block or damage the truck.
The window by which the chute was supposed to go through is too far away from the truck or too small for the chute.
When building or renovating, you should always remember the saying of better be safe than sorry. If you wish to have the truck go on your property or the back alley, we will be pleased to do our best to help you, but be aware that if any damage is caused to the truck or by it, you will be held responsible. Also, if the truck shows up and it cannot reach the dumping area, a fee will be charged for transportation (of course, because the concrete is not already mixed, you won’t be charged for the concrete, but with a regular concrete mixer, you would). We want, just as much as you to prevent such problems. If it looks like you’re not going to have any problem, great! If you have a doubt, we have a solution for you. A concrete pump. A second truck, equipped with hoses that will bring your concrete wherever you want it with no effort. Please contact our team at the office by phone about any questions you might have about the pump.
All concrete jobs must be finished or flattened. Even the top of a wall. This, for example, is a type of job you can finish yourself with the help of a simple trowel. Some other jobs will need a minimum of knowledge about concrete finishing but still be simple enough to do by you. We’re talking about sidewalks, slab for a spa or shed for example. And there is the last and most difficult type of job where will need expert knowledge or having a professional to help you (garage floors, basement floors, patios, balconies). It is sadly seen too often where people think they can handle it themselves and regretting it afterwards. A lot is to be considered to finish a large concrete slab, but the most important factor is your capacity to level the concrete or even more difficult, to create slopes toward a drain or your garage door. That is why we decided to have a finishing service. Our finishers, who have more than 25 years of experience, will be able to do the job for you.
It is important, when planning your job, that you decide which of these services you will require. Many of our customers have never worked with concrete. If you require the three services (concrete delivery, pumping and finishing) and decide to work with three different companies, your role of contractor will require that you deal in making these companies work together. As your probable first day as a contractor, they will be waiting for your orders and you may be confused. With Betonmobile.com, you will still be playing the role of the contractor, but only hiring a single company with different services that know each other and who work as a team to make the job easier for you.
However you unload the truck (directly with the chutes, wheelbarrow, pump), keep in mind that the concrete truck stays only a limited time for free. It will wait for you to finish your pour, but after a predetermined amount of time, extra charges will be applied if you need extra time. Please feel free to ask our sales team for more info about the time given for your delivery. Be better prepared than what you first planned for. If you are going to transport the concrete with wheelbarrows for example, plan a number of wheelbarrows and people to carry them according to your quantity and the distance from the truck to your pour without forgetting one or at best two persons to place the concrete once in the forms. Snacks and refreshments for your friends and family will come less expensive than extra time and the stress it brings.
To understand some characteristics of concrete, it can easily be compared to household products. Just take for example an orange juice or a soup. When adding water to your soup, you will gain easiness by having more for the same price, but you already know that it will be less tasty. Before explaining the soup example, we have to compare it to something else to measure how it can be spread or placed. A regular and good concrete has to be as liquid as wet mud. To make placing the concrete easier in their forms, many customers tend to do just like with the soup and ask the truck operator to add some water to the concrete. It’s not that bad if you add just a little, but each time the operator will add more water upon your request, the concrete will lose strength and quality. It’s a tough choice to make and that is why we invented the HD and we are really proud of it because it’s an exclusive product to Betonmobile.com. It will not allow you to pour a liquid concrete that places itself, but you will be able to add more water than you normally should while keeping the same strength and quality for minimal fees. Whether you take HD or not, keep in mind that nothing will ever replace the action of manually placing your concrete in your forms and making sure the concrete is well consolidated so that you don’t have weaknesses in its structure.
Step 4 : After the pour
Once the truck is finished dumping the concrete, he will need to wash himself. Being a mobile mixer, it doesn’t have a lot of equipment to wash. If you have a place where he can wash his whole mixer, the operator will be thankful. If not, he will be able to wash his mixer later, but take note that he will need to wash the chutes that you asked him to use. A small wheelbarrow or 2 or 3 buckets is more than enough for him to wash the chutes into if you do not allow him to wash on your pavement or your lawn. If you need the concrete pump, the washing is a bit more complicated.
When having two different companies for the concrete and the pump, you may end up having a lot of concrete left where the pump is parked. Because they don’t really talk to each other, when the job is done, the pump will be full and it cannot leave if full so he has to empty himself. In this situation, the amount of 5 or 6 wheelbarrows could be dumped and left there for you to deal with it. With Betonmobile.com, our different services work as a team to avoid such a situation. Perfection is really hard to reach, so we can’t promise you a concrete free cleaning, but we will do out best to leave as less concrete as possible. By mixing small amounts at a time when nearing the end of the pour, there won’t be much left in the pump but there still will be about 1 or 2 wheelbarrows to be dumped where the pumped is parked. You must plan a space in your job or property to dispose of that concrete.
Once the concrete is in place and the finishing is done, the biggest part of the job is over and a lot of people will stop at that point although there is still something to do so that you concrete can reach optimal quality. Curing the concrete. If we use once again a daily life product to compare concrete, let’s use this time a slow cook food like a roast beef. As slow cooking says it, you have to take the right amount of time to have the perfect taste. Well with concrete, the same laws apply. The cement powder, once mixed with water, to dry and strengthen itself, will produce heat that may be surprisingly warm at some point. Just like slow cooking, you will want to reduce that temperature so that it can dry slower. The best way is to simply sprinkle the concrete with water. Be careful though, because you have to do it at the right time. Adding water on a still too soft surface will damage the concrete. A little while after having completed the job, you will come and apply a little pressure with you finger. When your finger won’t print anymore in the concrete that means it’s time. A very small amount of water will be enough and being gentle when watering the concrete is important. Do not shoot the water directly. If you have a multi-function water nozzle, you might want to use the “mist” spray. It will be just what you need. 15 minutes, 2 times a day. You could also use a pierced water hose that you place over your slab. These are just examples. If you think of an other idea, your imagination is your only limit. The water will also keep the concrete humid. When the concrete dries, that’s when the process of hydration makes it gain strength, so the longer the drying period, the stronger it will get. A 25 Mpa concrete, if well hydrated, can reach up to 28 Mpa.