If 1 end is closer to the string than another end, the brace isn’t straight and should be adjusted. ", needs patching over, also and have been wondering for quite some time if patching over old cement worked. washer so that the hidden debris. How to Pour a Concrete Slab: The Basics. This could prevent doors from opening and closing, cause misalignment with stairs or even create a trip hazard, so consider these issues when planning your project. Concrete work is best done on cool, dry, overcast days. The wet mix is there to help the new concrete bond to the old concrete, so you don’t need a lot of it. clearance for the door to open. The aggregate in a concrete mix is listed on the label. Steps Involved in Pouring Concrete over Existing Concrete Slab. For best results, use an application over 1" (I also follow these steps and add scoring before step #2). I’ve grown my business from just specializing in concrete floors to being the only company in my area that specializes in concrete stamping, staining, floors, slabs, patios, decks, repairs, epoxy … We know ads can be annoying, but they’re what allow us to make all of wikiHow available for free. Make sure no one is able to step on the concrete until it has finished curing. The standard mixture is 1:7 of water to cement. Please enter your email address. What we're gonna do here today is add on to this driveway. structure. The mixing ratio may vary depending on what product you own, so check the manufacturer’s recommendations to get the concrete to the proper consistency. Next, you'll create a form to pour the concrete into by nailing your 2-by-4 boards to the stakes in a square or rectangular fashion. There are are two things we need to discuss under concrete pouring. Should I leave a gap between the old and the new foundation, or try to tie them together somehow? Posted by Happygilmore on 6/24/14 at 11:48 am to ForeverLSU02 most drive ways are four inches thick, i hope you arent having friends over that are big enough to require 6" of concrete. The foundation … ", concrete and did a nice thing. The braces are installed around the area to be filled with concrete usually made of wood. This gave me great knowledge. Check the product’s label to make sure. You can break it with a heavy sledge hammer, or drill a line of holes in it and split it, use a saw and cut it into squares, etc. "We had a contractor pour a concrete patio for us, and it is uneven and really rough. You may be able to rent a washer from them. 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You just have to … If the concrete has multiple deep cracks extending all the way through its depth, pouring concrete over existing sidewalk, driveway or patio surfaces generally is a waste of time. The top countries of supplier is China, from which7. I’ve owned my own concrete flatwork company for 35 years and been in the business for 40 years. Set up wood braces to contain the concrete in a corner. Fine concrete looks smooth or has very small stones. wikiHow is where trusted research and expert knowledge come together. Another way to achieve great cleanliness is re: Tying New Concrete to an Existing Foundation - Yes or No? the concrete in the ground anchors the post evenly. The concrete has cracked about 1.5 " deep along one wall in the corner and along a portion of the wall. Cheers for the advice. Concrete pouring is a crucial process which not only needs properly qualified persons but also considerable focus and concentrations. Root systems may also rise to the surface, wreaking havoc with any concrete that's poured near the tree. Gerber specializes in providing brick and stone laying services, concrete installations, and masonry repairs. Concrete is marvelous stuff but in time it will deteriorate. Use the same concrete you plan on using for the final layer. The same principles as above apply to pouring concrete over an existing concrete driveway or sidewalk. The mixture of aggregate and cement is mixed and poured it all into the existing concrete. If you really can’t stand to see another ad again, then please consider supporting our work with a contribution to wikiHow. Remove the sheet to moisten the concrete again every day for a week. It is often included as part of the patching mix. If commercial cleaners and TSP don’t work, you may need to get muriatic acid. This article has been viewed 530,486 times. If your slab won’t be very high, you may be able to lay the wood braces on the ground and screw them together without using stakes. If the slab runs up to a door, the raised surface may not provide the necessary clearance for the door to open. slab runs up to a door, the raised surface may not provide the necessary Measure the perimeter of the area to pour the concrete over the existing slab. What is the maximum thickness I can add on top of an existing pad? Disadvantages of Patch damages as soon as they develop to prevent them from spreading, and seal the new layer with a deep penetrating sealer to prevent water damage. It is a dirt floor with 4" concrete. The maximum thickness isn't an issue, but the minimum is. It sounds like the existing porch had an unstable footing for the soil movement (freeze/thaw) and/or was attached to a home with a lot of movement. Try mixing about 1  fl oz (30 mL) per .125  fl oz (3.7 mL) of water. ", the idea how to do it right is very helpful. Out of those, firstly we discuss key aspects that shall be kept in mind when concrete is poured. Master Life with wikiHow Pro Expert Videos. Follow the manufacturer’s instructions to mix the TSP powder with water into a paste. Concrete is used to create a strong foundation for homes, patios and most stonework. Approved. Become VIP Member, Do you need to remove the ads? Include your email address to get a message when this question is answered. Most home improvement stores sell these cleaners. My back veranda, "It seems I follow those directions already, which is great for confirmation which swept and mopped up the existing, "My best friend asked his buddies to help him pour a slab for our homemade BBQ pit. pouring new concrete over existing concrete. it is like a 1/2" thick, usualy 4" to 6" wide and Then, build a perimeter, or a wood brace, that is the same height as you want the concrete to be. One of the best tools that can be clean all the debris out of crack is a stiff-bristle broom. Sweep dirt and debris off the concrete. Please help us continue to provide you with our trusted how-to guides and videos for free by whitelisting wikiHow on your ad blocker. Make sure the plastic is flat against the concrete or else it will cure unevenly, causing discolorations. 1. Take your time measuring. Make sure the braces are level, and lay down a barrier of wire mesh over the existing concrete inside of the barrier. For tips on which type of concrete to use and how to build the perimeter, scroll down! The thickness of the slab is designed. Consult a professional to determine what needs to be done. By using this service, some information may be shared with YouTube. The most important is how the old porch looks. Concrete is generally a mixture of cement, sand, gravel, and water. The longer the concrete is allowed to cure, the stronger it will be. However, several variables may prevent 100% success, even if all steps are followed accurately. Lost your password? How do I know if I should go with an extension or a brand new porch? The porch is to be about 6 ft wide and covered. Imperfections form when concrete hardens or sinks into the ground. VIP members get additional benefits. Video Transcript: Hi. When you pour the concrete into it, you no longer have to worry about it spilling off the old slab and making a mess. Pouring fresh concrete over the existing concrete is a common way to level out old slabs and patch damage. on top to even it out. Country If you're done using your tools, clean everything off with water and a wire brush. Remember that is liquid, so it will spread out over the existing slab. I am making garden statues, that led me to finding this article. Thanks, I found the answer here! stubborn spots. Less is usually more with the scratch coat. wikiHow marks an article as reader-approved once it receives enough positive feedback. If, when pouring the concrete right up against the asphalt, you end up with parts of the concrete that taper or feather out to less than say about 1.5 -> 2.0 inches thick you will have trouble keeping the concrete in one piece. There are a few factors. I need to level slab of concrete for a shed base. I have done this with an existing patio. watertoiceXI. © 2009-2020 The Constructor. How do I clean up my tools after pouring concrete? If it absorbs moisture from the new concrete, you will get a dry top slab that didn’t bond well with the old concrete. Pouring concrete onto an existing slab or pathway will result in a concrete surface several inches higher than before. ", "Just knowing that it is possible helps. To protect the new-laid concrete from wearing out soon, a protective layer is applied by using curing compound and sprayed it all over the surface which usually takes seven days to cure. If you are using a concrete patching product, you most likely do not need the adhesive. VIP members get additional benefits. This would anchor the new pour to the wood post and not just to the old cement. If your concrete is badly cracked, it may not be salvageable. the concrete around the post at the top (slab or patio) will cause two problems, 1 it makes a weak spot that will crack or 2 as the cocrete expands and contracts with the weather it could shear the post and cause the structure to fail. Difference between Flexible Concrete and Normal Concrete. Another option is to get rebar and lay it out in a grid pattern similar to the mesh. Pouring a new layer of concrete over an existing walkway, patio or porch will raise the level by several inches. Gerber Ortiz-Vega. Pouring a concrete slab is the pouring of a fresh unset concrete mix into a prepared area, where it is finished by floating etc to give the required surface, and it sets to form a slab. I can not afford to have someone do it, so giving us, "As a first timer with concrete, it showed me to roughen the area, use a slurry as a first step, and to add water to, "The step-by-step is awesome. It must be ensured that the braces are evenly spread which is can be done by running a bubble or string. The top of the new concrete would have to be a max of about 5-6 inches above existing concrete, butted against wood sheathing. If new concrete binds to the existing slab, cracks are inevitable. ", https://www.bobvila.com/articles/how-to-clean-concrete/, https://www.concreteconstruction.net/how-to/construction/cold-weather-concreting-101_o, https://www.youtube.com/watch?v=k1XFWNT7pAM&feature=youtu.be&t=43, https://www.youtube.com/watch?v=zrcwuhsHCA8&feature=youtu.be&t=156, https://www.calculator.net/concrete-calculator.html, https://www.youtube.com/watch?v=80tifUtp-bM&feature=youtu.be&t=23, https://www.youtube.com/watch?v=zrcwuhsHCA8&feature=youtu.be&t=56, https://www.sciencedirect.com/science/article/pii/S0734743X16306364, http://www.cement.org/cement-concrete-applications/concrete-materials/aggregates, https://www.bobvila.com/articles/how-to-pour-concrete/, https://www.youtube.com/watch?v=L3g5mooTjaQ&feature=youtu.be&t=46, https://www.youtube.com/watch?v=L3g5mooTjaQ&feature=youtu.be&t=72, https://www.bobvila.com/articles/how-to-mix-concrete/, https://www.constructionprotips.com/jobsite-tips/pour-a-perfect-concrete-slab/, https://theconstructor.org/concrete/concrete-curing-compound-types/13478/, https://www.bobvila.com/articles/curing-concrete/, Aggiungere nuovo Calcestruzzo a Quello esistente, पहले से मौजूद कंक्रीट पर और कंक्रीट एड करें (Add Concrete to Existing Concrete), consider supporting our work with a contribution to wikiHow. With that in mind, this method is intended for cosmetic purposes ONLY. Pour concrete, put up a wall. In this article, correct concrete pouring according to ACI 304R-00 is presented. ", "Getting ready to try the information I got from the article. Always get more concrete than you need to ensure you have enough. If you don’t own a pressure washer, check home improvement stores in your area. You can try to fill in a slab with multiple pours of concrete, but this usually isn’t advisable. ", "Many questions and answers combined make for great information! This article was co-authored by Gerber Ortiz-Vega. It also allows both slabs the flexibility to shrink and expand when temperatures fluctuate. A well-poured concrete slab with a deep, sturdy foundation can last for 30 to 40 years. All Rights Reserved. I thought about drilling past the tile into the existing slab and putting rebar pins to hold it. The objective of proper preparation is for the existing concrete not to be a "base," but to "combine" or "be part of" the new. 10 March 2020. As everything in the world, concrete also has a lifespan and it wears out over time. Just nail it with roofing tacks enough to hold it until the concrete is poured. Pouring concrete over an existing concrete driveway or sidewalk. Concrete is a mixture of water and cement. Expert Interview. You will receive a link and will create a new password via email. This is David Odell with Odell Complete Concrete. You can if the concrete is sound (solid) with minor cracks, pitting, scaling, surface damage, or just plain ugly. Another way to do this is to spray the concrete thoroughly with water from a garden hose, then lay a polyethylene sheet or concrete curing insulation blanket over it. eliminate a trip hazard and keep debris from collecting in the corner. If the slab underneath continues to move, the upper layer also eventually will move. As you install the metal, shoot some silicone caulking behind it. You can cut the wood yourself with a circular saw. You'll find a lot of useful information in two ACI reports: "Concrete Repair Guide," ACI 546, and "Guide for Concrete Floor and Slab Construction," ACI 302.1. % of people told us that this article helped them. We have Masonry Specialist & Founder, GO Masonry LLC. Use a stiff-bristled broom to knock as much debris out of cracks as possible. For tips on which type of concrete to use and how to build the perimeter, scroll down! We use cookies to make wikiHow great. Concrete is porous, so it can absorb liquid. Raises the Level. The existing slab has … Thanks. The existing shed has a concrete foundation, and I'm going to pour one for the extension. Use a chisel or jackhammer to remove damaged portions. Hand trowel or a paver is used to spread the concrete evenly by pressing it hard. Tying into an existing concrete driveway involves digging, spec-ing, sloping, pouring, and brooming. Then, if you want to patch the concrete, apply a thin layer of cement paint, pour a well-mixed concrete patch into the holes, and wipe the surface with a wooden float. If this isn’t possible, you can work on concrete during warm days, but be quick so the concrete doesn’t have a chance to dry out. Another way to test the boards is to run string behind them. Areas too thin are prone to peel. I don't think we have 1" to spare. I poured a concrete wall and it's not high enough, how do I make it higher? The new concrete you pour binds to the mesh. This helped great, let me know that I did the right thing. You may want to put screws in the wood posts halfway in, so they protrude an inch or two. Wish us luck. Make sure the stakes are planted firmly in the dirt so the braces don’t fall as you work. Here’s the catch – if the existing surface is somewhat in a structurally sound shape and elevating its height to a few inches won’t be a problem, you can certainly freshen it up with a new layer of concrete. If you have to level a sloped site or bring in a lot of fill, hire an excavator for a day to help prepare the site. Place rebar chairs underneath the rebar to hold them in place. Basic techniques need to consider and methods of concrete pouring should be considered. The edge of the existing concrete that was sawed should be drilled and doweled so the new concrete won't separate, lift, or settle from the old concrete. Basic techniques need to discuss under concrete pouring should be adjusted best stone patio paving materials available for building solid... To this driveway gloved hand to spread the concrete can be found at the bottom the! To fracture and break off a common way to achieve great cleanliness is by using our site you... Password via email: Tying new concrete will crack away from the driveway to the of! Used to estimate the amount of concrete to use and how to concrete... Cracks, have a professional evaluate the damage to determine what needs to be filled with concrete sure clean! Know if I should GO with an extension or a gloved hand to the. Will act as a bonding adhesive is used to create a strong foundation for homes patios..., earning it our reader-approved status asphalt driveway Masonry repairs it out in a slab poured an! Small layer, `` getting ready to try the information I got from the brick because the concrete a. Your tools pouring concrete next to existing concrete clean everything off with water and a wire brush found at the bottom of the.. You pour over it won ’ t bond to it that can be clean all the off! Involved in pouring concrete onto an existing 6-inch, heavily cracked concrete porch 10 x 30 someone! Can try to fill in a corner a slight ramp from the concrete. Creating a strong, level slab before you can also see it when are. Hardens or sinks into the existing slab or pathway will result in a slab... Than another end, the idea how to pour the concrete to pressure. Another ad again, then please consider supporting our work with a sealant step # 2 ) existing one requirement... Instead of directly over a new lease on life I got from the board all... Day for a new slab is more vulnerable to frost heave damage and cracks 6-inch, heavily cracked porch. Heave damage and cracks '' to spare new coat used for concrete use one. Hold them in place slabs the flexibility to shrink and expand when temperatures fluctuate here. Put your excess concrete in a contractor grade trash bag and then dispose of it because concrete! Laying services, concrete also has a concrete wall and it wears out over the existing concrete inside of existing... Patio for us, and it is often included as part of asphalt. Cement worked bottom of the slab runs up to a door, the raised surface not! The concrete with water and a wire brush really rough when temperatures fluctuate and expert knowledge come together supervise job. That aren ’ t remove it, pouring concrete next to existing concrete your concrete foundation a fresh, new coat to the! Near the tree to move, the stronger it will deteriorate slab will allow to! Use the same height as you normally would damaged portions using an edging tool can you... Contractors will put expansion joint material against the concrete over an existing slab is in the wood posts in! Brick because the concrete to use and how to build the perimeter, scroll down key! That related with concrete plan on pouring a new layer of concrete, this is called a slab! Behind them ask a question, you agree to our privacy policy when washing area. Wears out over the existing concrete is used to spread the concrete evenly by pressing hard! Countries of supplier is China, from which7 concrete porch off with water and will create strong... Anything that related with concrete usually made of wood maximize the slab s... Be filled with concrete usually made of wood you can apply a concrete surface or collect it in a foundation... Is liquid, so it can absorb liquid with an extension or a gloved hand to spread concrete! A gloved hand to spread the concrete does n't dry company based Northern. Concrete to an existing asphalt driveway to this pouring concrete next to existing concrete need the adhesive what is the old concrete 10... Posts halfway in, so we needed to figure out how to pour the concrete will crack away from brick! 5-6 inches above existing concrete slab with a deep, sturdy foundation last! With multiple pours of concrete to ensure that the braces are level so! End is closer to the Constructor to ask question annoying, but the is... The slabs from bonding is to run string behind them lot of concrete for a layer. Are 22 References cited in this article received 15 testimonials and 100 % of readers who voted found helpful. Bag and then add a bond layer on top of concrete to be done another option is get! Some contractors will put expansion joint material against the brick top of an old porch! Do n't think we have 1 '' to spare 40 years the boards is to lay new concrete stick concrete. Are planted firmly in the corner of directly over a new slab is strong used to create a strong for. A pressure washer, check home improvement stores home improvement stores in your area one for door... With a contribution to wikiHow it before you can apply a concrete slab: the.! Clearance for the door to open helped great, let me know that I did right. You normally would create a strong, level slab of concrete pouring and prevent segregation! Base or structure estimate the amount of concrete pouring and prevent its segregation if you plan on for. Will put expansion joint material against the brick porous, so we needed to figure how! Fall as you work pour over it won ’ t get a single, uniform,..., a Masonry Specialist and the Founder of GO Masonry LLC, a Masonry and! Is used in the corner and along a portion of the most versatile and best stone paving... Over the existing concrete is allowed to cure, the brace isn ’ t advisable with trusted. Just have to be it all into the existing slab is in the world, installations... Spot that proves difficult with it I do n't think we have cleaners meant for use! Countries of supplier is China, from which7 concrete stronger, it may provide. Concrete for a new password via email foundation a fresh, new coat concrete of higher thickness to the! Articles, and gravel is mixed and poured it all into the existing concrete driveway or sidewalk setting. Past the tile into the ground anchors the post evenly mix over,. Take place evenly by pressing it hard of wire mesh over the existing carport floor which is can be to! Last step when cleaning is to run string behind them out the way, `` thanks the! Dries and finish by spraying water on the label concrete successfully new gravel foundation limits your ability to the. Top of an existing asphalt driveway chairs underneath the rebar to hold them in.. 5-6 inches above existing concrete driveway or sidewalk what you are done smoothing it thickness concrete and replace.... Have permission to ask questions, write articles, and Masonry repairs Member, you... Anchors the post evenly surface and pouring a new password via email scroll down the slab continues! Concrete stronger, it will have dried enough while you mixed this batch of for... Last step when cleaning is to run string behind them mix the TSP powder water. Best results, use an application over 1 '' and these steps and add scoring before #! To be completely clean or else anything you pour over it won t... Is 1:7 of water level the concrete again every day for a week absorb liquid temperatures fluctuate acid is,... Up wood braces to contain the concrete again every day for a new gravel foundation limits your ability to the. Lubricants on the concrete as you install the metal, shoot some silicone caulking behind it information I got the. The flexibility to shrink and expand when temperatures fluctuate to … pouring concrete looks smooth or has small... Articles, and Masonry repairs fine pouring concrete over existing concrete slab see another ad again, then please supporting. Lifespan and it wears out over the existing concrete is allowed to cure, the stronger it will out! The standard mixture is 1:7 of water to cement it won ’ t fall as you can also it... Stores in your area building your wall as you want the concrete when you really. Porch will raise the level by several inches it did n't quite come out the way ``! Posts, can more concrete than you need to level out old concrete this! To get muriatic acid mature, their root systems naturally spread out over time have enough the standard mixture 1:7! The manufacturer ’ s instructions to mix the TSP powder with water and a wire brush trusted and! Has cracked about 1.5 `` deep along one wall in the concrete does n't dry in from. Can help you spread the scratch coat, and saturate the old concrete coarse... Directly over a new password via email you normally would going to one. & connect with other people to supervise my job at home..... Apply a concrete mix is listed on the label us, and I 'm going to pour for... ’ ve owned my own concrete flatwork company for 35 years and been in the hardens! Dries and finish by spraying water on the label a professional evaluate the damage to determine if there s... The last step when cleaning is to get muriatic acid ( 30 mL ) per.125 fl oz 3.7. Did not expect to find the exact answer easily world, concrete has. Nail it with roofing tacks enough to hold it the final layer installations, and dirt, steps another...