4 Ways To Bond New Concrete To Old Concrete (2023)


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From www.swimmingpoolsteve.com/pages/bond-concrete.html - Bonding new concrete to old concrete is an application specific process. There are a lot of methods to use but it would be easy to use the wrong one for your application. Learn more about the different ways to bond new concrete to old conrete in this video including latex fortifier, SBR latex, PVA and thinset.

Introduction To Concrete Bonding - youtu.be/nadCPbyCtPU

Bonding New Concrete To Oily Concrete - youtu.be/z8m9sh9G2DY

How To Prepare Old Concrete For Bonding - youtu.be/1CTRFEyA6HA

How To Acid Wash Concrete - youtu.be/VvO4yQBHm58

How To Bond New Concrete To Old Concrete With A Latex Slurry - youtu.be/modf3DcMI7c

Bonding New Concrete To Old Concrete With SBR Latex - youtu.be/X9L9_OPhzzg

How To Bond New Concrete To Old Concrete With PVA Slurry - youtu.be/MZKs3rExk94

How To Bond New Concrete To Old Concrete With Thinset - youtu.be/EKLvfGsqqcM

Original concrete bonding video with almost 1M views - youtu.be/ElNThXvtJ18

#swimmingpoolsteve #concrete


In this video we're going to be looking at some concrete that has been bonded using a an assortment of different methods, uh, starting from the left here.

We've got an acrylic fortifier or acrylic latex.

And then we have an sbr latex product.

Then we have pva polyvinyl acetate.

And then we have a method using thinset as an intermediary layer between old concrete and new concrete in order to create a bond and I'm excited to see how this turned out so let's open this up and take a look bonding new concrete to old concrete is probably quite a bit harder and more technical of a process than most people are going to appreciate.

There are a variety of different concretes, different admixtures or things.

You can put into the concrete.

And this changes the physical properties of it or the the mechanical properties of like.

It might be a really viscous concrete versus something that's.

You know, different than that like the point is is that there's a right concrete for every application.

And as a, you know, just a a hobbyist or an enthusiast level, concrete worker, it's it's, a pretty deep world and you're gonna have trouble finding the exact right thing to use for the exact rate application and that's, why professionals exist? You know, if you're just doing a little bit of, you know, fun concrete work around your house and statuary or fixing a divot in the sidewalk that's, not really such a big deal.

Have a go at it, see how it lasts, you know.

And if it fails in the first year, then you didn't do such a good job and maybe go back to the drawing board and try again, but that's.

What we were looking at here is some of the different ways in which you can bond new concrete to old concrete in my original video on the subject, which is a very simple and straightforward video, which more or less was summarizing to clean the concrete well and make sure it's damp and then apply a slurry and put your new concrete on top of that and it's a pretty sound process.

But it's, not a one process fits all kind of thing.

There are a ton of different ways to bond new concrete to old concrete.

I will be really interested to see how some of these turned out all right so starting with the.

So, as you can see, we clearly have two layers of concrete here, mortar.

In this case, which just means concrete, but it doesn't have rocks in it it's just sand as the aggregate.

And the first thing that you want to do it's like, okay, we have two pieces of concrete.

They don't immediately fall in twain.

So they're, not fully separated, but does that mean that they're bonded no not at all.

And the first thing that I'm gonna do to determine if it's bonded is something called sounding running something like a hammer over top of concrete will reveal very readily when it has delaminated, because it will sound hollow, noticeably hollow and that piece there and it's pretty thin.

So it kind of sounds hollow.

Alright, if you can imagine when it's four inches thick, it sounds a lot more solid, but sounds pretty solid to me.

So I'm, not going to do much more with that we'll just get them all out of the mold here.


So this is the sbr latex again.

You can clearly see the there are multiple layers existing here again, that sounds pretty good to me now, I'm, confident with all these methods here, because these are all standard methods that you would use to bond new concrete to old concrete save for from my experience.

Just the thin set that's, not one that I normally do but I'm a swimming pool, contractor backyard, contractor that's, most commonly used on an inside process.

I've done it a couple of times.

And I think it works, pretty darn good because that thinset, as I mentioned in another video is heavily bonded with polymers and bonding agents, and you can bond that stuff to pretty much anything.

So it wouldn't surprise me at all if it works really well to bond new concrete to old content.

Now thinset comes in a lot of different colors that stuff in particular was white.

So if you saw the other video, you can see that it was a white product and that's, why you can see a little bit of a white coloration there between the layers, but again, that sounds pretty solid to me.

And I think what we've got here is pretty effectively.

We've managed to bond new concrete to old concrete in four different ways where this would start to differentiate itself is what if I just threw all these into my pool and just left them there for a month, would they all still be secured bonded or maybe would one or more of them sound delaminated or possibly even fallen two at that point? Or what if I had some of these, and I left them out in winter where at my house, we could get minus 30 minus 40, sometimes in the winter, what happens then or even worse than that, the springtime where it freezes at night, but it's kind of nice and warm during the day.

And then it freezes at night again, and then it rains, and then it freezes and snows and melts and rains freezes snows melts again.

And I throw some salt on top of it it's, a disaster for concrete in that kind of environment would all of these still remain bonded it's hard to say, it's, a very complex subject and some concrete workers professional concrete workers are kind of of the opinion.

You really can't bond, new concrete to old concrete, nor should you try but it's something that is application specific.

I always say to them, well, I bond new concrete to old concrete when I set tiles in a swimming pool.

Are you proposing to me that every time I need to put new tiles in the pool? I should jack him around the entire pool and build a new concrete pool, because that doesn't sound like a sound plan to me.

So again, application specific.

But generally speaking bonding new concrete to old concrete is hard there's, a lot of steps involved in it.

You gotta do all of them if you shortcut them, you're, very likely to have a problem.


4 Ways To Bond New Concrete To Old Concrete? ›

The most effective way to ensure a really good bond is with a scratch coat. This is simply a very wet coat made up by mixing the repair product with water. Mix up a small amount of the repair material to a soupy consistency. You don't need to measure the water—just turn the stuff into slop.

How do you make new concrete adhere to old concrete? ›

The most effective way to ensure a really good bond is with a scratch coat. This is simply a very wet coat made up by mixing the repair product with water. Mix up a small amount of the repair material to a soupy consistency. You don't need to measure the water—just turn the stuff into slop.

What are the methods of joining old and new concrete? ›

Bonding Fresh Concrete to Existing Concrete Surfaces

Overlays or patching materials of new Portland Cement Concrete (PCC), terrazzo, mortar, grout and extruded curb based on Type I through Type V cements or White Cement may be structurally bonded with liquid epoxy adhesives to existing concrete surfaces.

What is the best adhesive for concrete to concrete? ›

Loctite Epoxy Metal/Concrete is a fabulous choice if you want to bond concrete, metal, glass, ceramic, and wood.

How do you bond fresh concrete to hardened concrete? ›

During repair work, use milling or grinding to reach hard concrete and then apply a bonding agent. Sand-cement and water-cement grouts are economical and practical adhesive agents that can be used for bonding hardened and fresh concrete. The sand-cement grout consists of 1 cement: 1 sand: ½ water.

What is the bonding agent between old and new concrete? ›

Epoxy resins are widely used in the construction field because of their high compressive strength, strong adhesion, chemical resistance and other unique properties. They are available for the bonding of fresh concrete to the old concrete. Additionally, they are also used for the bonding of concrete to steel.

Should you pin new concrete to old concrete? ›

Any time one is to attach new concrete to old concrete, it is likely for cracks to form and the sections will begin to separate. One way to help prevent that when attaching them is to use rebar to pin them together.

What is cement bonding adhesive? ›

QUIKRETE® Premium Concrete Bonding Adhesive is an exterior/interior grade synthetic emulsion formulated to permanently bond new concrete, plaster, and stucco to existing concrete, plaster, and stucco or can be used as a primer for QUIKRETE® self-leveling floor resurfacers.

What are the two ways of casting concrete? ›

The most common casting methods are:
  • Wet cast.
  • Hand-packed.
  • Sprayed.
  • Troweled.
Jan 1, 2015

What is bonding cement? ›

Concrete bonding agents are natural or synthetic materials used to join the old and new concrete surfaces. This agent can also be used to join the successive concrete layers. This chemical helps to allow different concrete surfaces to behave like a single unit.

What is the best concrete bonding glue? ›

  • STICKYSTONE | Vertical Hardscape Adhesive. New.
  • Structure Bond Construction Adhesive.
  • BorderBond Fortifier.
  • RG+ Elastomeric Adhesive for Concrete & Masonry.
  • Structure Bond Gun Cleaner.

Does Gorilla Glue bond concrete to concrete? ›

GorillaWeld is an incredibly strong and heavy duty steel bond epoxy. The formula has a 4250 PSI bond strength and sets in just 10 minutes. GorillaWeld is also waterproof and versatile, creating a long lasting, permanent bond to: metal, plastics*, concrete, ceramics, PVC, fiberglass and more!

Will liquid nails bond concrete to concrete? ›

LIQUID NAILS® Concrete & Mortar Repair, (CR-805), is a weather-resistant indoor/outdoor acrylic compound with silicone, ideal for repairing and sealing cracks and joints in concrete and masonry surfaces. This easy-gunning sealant dries gray similar to concrete or can be painted.

Does cement harden like concrete? ›

Mortar is composed of cement and sand. Adding water to this mix activates the cement so that it hardens, or cures, just as with concrete.

Does cement harden into concrete? ›

Concrete is completely fluid before the cement sets, then progressively hardens. The cement and water mixture that has crystallized in this way encloses the aggregate particles and produces a dense material. The concrete continues to harden over several months.

Does mortar stick to concrete? ›

Because mortar will stick to the concrete slab and the wood subfloor, and mortar will stick to mortar, then it would only make sense that mortar would work for leveling or patching, right? Well, the answer is actually no. Mortars cannot be used to level or patch a floor – ever!

How do you bond two pieces of concrete? ›

  1. Apply the two-part concrete epoxy. Apply the epoxy glue or putty to one or both surfaces, as per the instructions, and remove any excess epoxy glue as quickly as you can.
  2. Leave it to dry. Support or clamp the bonded surfaces together and leave them to dry for the time specified on the product's instructions. ...
  3. Finish.

How do you bond two layers of concrete? ›

Here's our five-step guide to bonding fresh concrete to an existing layer.
  1. Loosen Old Concrete. Before you even begin to think about pouring a new layer of concrete over the top, you have to start preparing the existing layer. ...
  2. Dust the Surface. ...
  3. Mix the Bonding Agent. ...
  4. Apply the Bonding Agent. ...
  5. Apply the New Cement.
Apr 4, 2023

What are the different types of bonding cement? ›

The main types of bonding agents used in the construction industry are latex emulsions and epoxies. Although good adhesion may be obtained without a bonding agent, generally a bonding layer consisting of cement and sand slurry, cement/latex slurry or epoxy increases bond strength.

Can you pour 2 inches of concrete over existing concrete? ›

Can You Pour Concrete Over Concrete? Yes, you can pour fresh concrete over existing concrete. As long as your concrete is in mint condition, this task is doable. If you decide to pour a new mixture over an old slab, be sure it is at least 2 inches thick.

How thick can you apply surface bonding cement? ›

Apply Surface Bonding Cement with a minimum thickness of 1/8” up to a maximum thickness of 3/8”. Masonry and Concrete Apply a thin coat of Surface Bonding Cement (with a flat steel trowel) over the masonry or concrete then immediately double back applying the Surface Bonding Cement to the desired thickness.

Is concrete adhesive stronger than mortar? ›

Mortar is not as strong as concrete and typically is not used as a sole building material. Rather, it is the "glue" that holds together bricks, concrete blocks, stone, and other masonry materials.

What is an example of a bonding agent? ›

A few examples of different universal bonding agents are Futurabond U (VOCO America), OptiBond XTR (Kerr), Prelude One (Danville Materials), ALL-BOND UNIVERSAL (BISCO Dental Products), and Scotchbond Universal (3M ESPE).

What are the 3 ways of casting? ›

Mainly there are 3 Different Types of Casting processes. They are Die casting, Investment casting, and Sand casting. Each of them provides its own unique fabrication benefits.

What is the best concrete mix for casting? ›

QUIKRETE® Fiber-Reinforced Concrete, because of its high strength and smooth surface finish, is the best choice for the cast projects that follow. In addition QUIKRETE® Sand Mix and QUIKWALL™ Surface Bonding Cement are flexible enough to be used in a variety of cast projects.

What is reverse cast concrete? ›

The counters are made using the reverse casting technique. This means the concrete will be poured into the mold and the concrete against the bottom of the mold will be super smooth because it forms against the melamine.

Is there a bonding agent for concrete? ›

Quikrete 1 Gal. Concrete Bonding Adhesive permanently bonds existing concrete, plaster and stucco to new concrete, plaster and stucco. It can be used indoors and outdoors on concrete overlays 1 in. or thicker.

What is bond strength concrete to concrete? ›

The bond strength of concrete is a function of compressive strength and is approximately proportional to the compressive strength up to 20 MPa. For higher strength, the increase of bond strength is progressively smaller. The bond strength of high-pressured steam-cured concrete is low.

What is the bonding agent for structural concrete? ›

INTRALOK is ideal for topping, leveling, patching, and dressing of concrete and masonry. As a bonding agent, it improves the adhesion of concrete or mortars. Mortars modified with INTRALOK provide excellent adhesion to a variety of surfaces, including concrete and masonry.

Do you need a bonding agent for concrete to concrete? ›

Concrete does not adhere to: Concrete – Dried concrete doesn't have any natural bonding agents, so in order to get wet concrete to bond to existing concrete, a bonding agent will need to be used.

What is the best permanent bonding glue? ›

Cyanoacrylate Super Glue - Best for Precision Work

Cyanoacrylate is the long name for super glue which can be used for all types of repairs and projects, including use with plastics. Super glue works best when surfaces are less smooth so consider sanding the plastic surface before applying the adhesive.

Can you join two pieces of concrete? ›

Since cement lacks any natural bonding agents, newly-poured concrete won't naturally bond to the existing slab. You'll need to either use a bonding agent to adhere the two layers together or use an unbonded overlay method. Condition-affected life span: Properly installed concrete can last for over 50 years.

Can I use glue instead of mortar? ›

In short, brick glue is an effective and convenient substitute for mortar in many masonry uses, but when using it, you should be aware of its disadvantages.

What epoxy is used for concrete? ›

Quikrete 8.6 oz. Epoxy Concrete Repair is a specially designed repair product suitable for most concrete and masonry surfaces.

What is the strongest glue in the world? ›

The name of the world's strongest adhesive is DELO MONOPOX. This is a modified version of the high-temperature-resistant DELO MONOPOX HT2860. This epoxy resin forms a very dense network during heat curing.

What is the strongest liquid nails? ›

Liquid Nails Fuze*It Max interior and exterior all-purpose construction adhesive delivers the strongest bond from start to finish* with both exceptional grab and long-term strength. Fuze*It Max sets the new standard for adhesives.

Is Liquid Nails permanent? ›

LIQUID NAILS® Small Projects & Repairs Adhesive (LN-700) is a fast-bonding, permanent, waterproof adhesive formulated for most common materials. It works where a hammer and nails can't. Resealable cap keeps product fresh.

Will concrete stick to set concrete? ›

Concrete does not adhere to: Concrete – Dried concrete doesn't have any natural bonding agents, so in order to get wet concrete to bond to existing concrete, a bonding agent will need to be used. Molds – Most concrete molds are made from urethane rubbers, which are designed to be resistant to concrete bonding.

What is bonding agent for concrete? ›

Polyvinyl Acetate( PVA)

This agent is mainly used for the repair works in concrete. PVA offers great water resistance, ultraviolet stability, and aging characteristics.

Will new mortar stick to old concrete? ›

Concrete, mortar or similar materials are not designed to stick or bond to old surfaces. You will not get any satisfactory results if you simply add new mortar to old. It just doesn't work. Using a modified thinset mortar would be the preferred method for this type of installation.

Can you pour self-leveling concrete over existing concrete? ›

You can pour self-leveling toppings or self-leveling overlays over concrete surfaces you didn't think were salvageable, saving time and money. “It's faster and easier than pouring new concrete,” says Paul Koury, president of Westcoat Specialty Coating Systems.

What is concrete bonding primer? ›

This concrete bonding primer penetrates and bonds to etched concrete, enhancing the adhesion of the top coat finish. Ideal for use under Valspar Latex Porch & Floor Paint. Maximum adhesion to concrete for a flawless top coat. Ensures resistance to peeling and flaking.

What is the use of BondCrete? ›

BondCrete is suitable for Tiling, adhesive for craft work, patching of most surfaces, sealing concrete, rendering surfaces and most cement applications. BondCrete is widely used in the building and renovating industry.

How do you use concrete bonding adhesive? ›

Apply to surface with a brush, roller, or paint-sprayer to the thickness of a coat of paint. Place new concrete, cementitious topping, portland cement based stucco, or cementitious based repair material as soon as the QUIKRETE® Premium Concrete Bonding Adhesive has dried. A drying time of 2 to 3 hours is typical.

What is the best product to repair concrete? ›

Vinyl Concrete Patcher is ideal for making smooth repairs to crack or chipped concrete floors, sidewalks or steps. It has strong adhesive properties allowing it to be applied down to a featheredge. Quikrete 10 lb. Vinyl Concrete Patcher is made of a special blend of vinyl resin, fine sand and Portland cement.

Will thinset mortar bond to concrete? ›

Thinset mortar is an adhesive used for tile installation, adhering these materials to a cementitious substrate. It works on surfaces such as cement, concrete floors, a floor or wall covered in cement backer board, or a waterproof membrane over the top of these materials.

When should you not use self-leveling concrete? ›

Polymer-mixed, self-leveling concrete also does not cure very well on non-horizontal surfaces. It will therefore be unsuitable for use on vertical walls. It is also not suitable for use where heavy machinery or harsh chemicals are applied.

How thick can self-leveling concrete be poured? ›

QUIKRETE® Fast-Setting Self-Leveling Floor Resurfacer (No. 1249-51) can be installed from 1-1/2 inch (38 mm) thick to a feather edge, although a ¼ inch (6.3 mm) minimum thickness is required for heavy traffic areas.

What is a cheaper alternative to self-leveling compound? ›

Sand Mix, Portland Cement & Gypsum-Based Compound are practical alternatives to the self-leveling compound. These options are cost-effective materials that are ideal for smoothening up your floor. At the same time, you can also try Drywall Compound and Foam.

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