What are concrete expansion joints and why are they important? The joints are cut at similar intervals in the structures to prevent development of cracking or splitting. Other videos tell you SIka is the right option of many out there. Expansion joints. The expansion joints are incorporated to endure the stresses. are required to have joints every eight feet horizontally and vertically. Expansion Joints: Where, When and How By James M. Fisher, S.E. DECK-O-JOINT is a decorative expansion joint for use wherever concrete is placed. In hot weather, concrete might crack if joints are not cut within 6-12 hours after finishing concrete. Expansion joints are used to allow the slab to move and not put stress on whatever it abuts. Expansion joints allows for movement without damage to the concrete. Learn why Meadows Expansion Joint solutions (filler material) are trusted by architects and contractors worldwide! Concrete joints are normally used to prevent cracks when the concrete shrinks by creating forming, tooling, sawing, and placing joint formers. On the fence side I'm going to place a length of treated wood as the border of the form and leave it there. However, cracks developed may be repaired by using suitable concrete sealer. Hanson on Twitter Hanson on LinkedIn Hanson on Facebook Hanson on Youtube. All concrete will shrink slightly as it dries and, when it’s set, will expand or contract depending on the ambient temperature. The only thing that we can do is control where it cracks with proper concrete control joint spacing and depths at the right time. The material should extend the depth of the slab and extend the full width of the slab. A concrete driveway may experience temperature differentials from 20 degrees below zero to … First, snap a chalk line across your driveway slab and follow this line as you cut. Scrape the sides and top of the joints to leave a clean finish. 2. Make sure joints are cut deep enough: they need to be at least a quarter of the thickness of the slab. Expansion joints. Long stretches of concrete do not require intermediate expansion joints. To find out where you can buy Growtivation products visit our online Where to Buy facility or contact the friendly team at Growtivation for advice on 0800 197 8885 or email firstname.lastname@example.org. Why Joints Need Quality Sealant. There are two types of joints in concrete driveway slabs, Expansion Joints and Control Crack Joints.The two we repair most of the time is diagrams 1 and 2 below. According to several industry sources, expansion joints, even at 50-foot intervals, are not necessary for the sidewalk project. Internal restraint is created when one part of a slab shrinks more than another, or shrinks in a different direction. An expansion joint is a component that adds flexibility to the pipe system. I had a house built with a double drive, and 4 inches of concrete poured over Mesh/wire. The tear-off strip on top of Abelflex is there for a reason that is often overlooked. Concrete expansion joints in roads and bridges are created in asphalt or concrete to allow material expansions and contractions due to the changes in temperatures, or due to road or bridge movement. or outside (driveways, patios, entries, etc.) For a 100mm slab, cut the joints at least 25mm deep. Before pouring the concrete it is important to make sure the fibreboard strips are the same height as the depth of the concrete to be poured. This article emphases on need of expansion … It stands up well to petroleum spills and harsh cleaning products. An expansion joint is a material placed in the cracks (or joints) between concrete slabs to protect the slabs from cracking when they contract and expand as the temperature changes. Joints are most effective when the aspect ratio of the slab is kept to 1:1, for example 5m x 5m if the slab is a narrower than it is long it is possible to increase this to a maximum aspect ratio of 1.5 for example 2m x 3m, don’t leave the placing of concrete expansion joints to chance and enlist the services of a structural engineer if several are required. I n the most basic sense, the need for anexpansion joint in a structure depends on the consequence of not having an expansion joint. Concrete undergoes expansion due to high temperature when in a confined boundary which leads to cracks. for a 100mm thick slab, this means they would be spaced approx. In cooler weather, expansion joints can be cut with saws after the concrete has hardened a little. Concrete Joint Sealant Preparation. In addition to the concrete mix and the weather conditions, determining when to saw concrete is based on the concrete's hardness as well as the type of cutting equipment used to make the saw cuts. Temperature changes. SITEWORX Fibreboard Expansion Joint Filler comes impregnated with bitumen, to aid moisture resistance. An expansion joint or movement joint is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials, and vibration, or to allow movement due to ground settlement or seismic activity. Expansion joints allow space in which concrete can contract and expand without causing cracks. Early-entry saws make a nice, clean cut for decorative concrete joints. One thing that I was taught in my years as a concrete finisher is that there are two things in life that are certain, the first is of course death and the second is concrete is going to crack. An expansion joint, also known as a movement joint, is designed to absorb the natural expansion and contraction of materials as the temperature drops or rises. Referred to as a movement, expansion or stress relieving joint, expansion joints are often used when tiling large floors to break up the floor covering in to separate sections. However, more likely, it will look particularly unsightly. They are also installed to absorb vibration, hold parts together or allow those parts to move as the ground settles or if there is an earthquake. A concrete expansion joint is also used to separate a concrete driveway or patio from a garage slab, … Use A Concrete Saw. In this condition, if you don't want to use a grooving tool to cut joints, there are early-entry dry-cut lightweight saws that It is composed of cellular fibers securely bonded together and uniformly saturated with asphalt to assure longevity. The Expansion Joints are installed at set locations to assist with the creation of a weakened plane where the concrete material is … One of the common ways to repair concrete expansion joints involves some basic tools and a lot of time. Without expansion joints, it is contact with soil and brickwork that is being relied on to contain the concrete shrinkage. Figure 1a: Joint Spacing in Meters. Asphalt is a self-sealing material, so it rarely requires an additional sealer. They are commonly found between sections of buildings, bridges, sidewalks, railway tracks, piping systems, ships, and other structures. How to caulk a concrete expansion joint. It’s important to know that concrete joints need to be prepped before you seal them – there are two products that you’ll need for this: Concrete, like many other materials, expands when heated and shrinks when cooled. One Useful Tip. There are two types of expansion joint filler , foam and fibreboard. This is an out-dated practice that allows slabs to migrate and transverse contraction joints to open too wide causing joint … For more information about Hanson concrete or to request a quote, please use the contact details on this page. Additional joints should be included through the concrete slab area, spaced at approx. Improperly sealed expansion joints can sometimes be to blame, which is why it is so important to use a proper expansion joint filler for concrete when doing repairs. Concrete expansion joints are particularly important where there have been consecutive concrete pours and are also useful when laying concrete within an area bordered by walls or buildings or if objects such as manhole covers need to be incorporated. The purpose of an expansion joint is to allow the concrete slab to expand and contract with temperatures changes, without cracking the slab. An expansion joint or movement joint is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials, and vibration, or to allow movement due to ground settlement or seismic activity. Every concrete slab, inside (basements, garages, etc.) Installing Concrete Expansion Joints. Utilising Expansion Joints or Control Joints as they are also known, is the most common method for controlling cracking when joining concrete slabs. Some examples of such stationary structures are: a house, a building or deck posts. Concrete, like many other materials, expands when heated and shrinks when cooled. Tilted Concrete Solutions not only provides Top Rated Local® concrete leveling services in Houston, but we also provide industry-leading expansion joint repair. every 3 metres. First, snap a chalk line across your driveway slab and follow this line as you cut. Concrete joints are used to compensate when concrete expands or shrinks with changes in temperature. A pliable material is used (asphalt coated, cork, plastic) to construct these types of joints. Proper use of contraction joints at short spacings of 5 feet will allow for proper movement of the individual sidewalk slabs. Also, the expansion joint must be isolated as well. Placing joints under walls will mean they won’t be seen. with treated lumber for the expansion joints. 30 times the slab thickness, e.g. Sakrete Concrete Fiber Expansion Joint is a multipurpose expansion contractor joint filler. The technical term structural engineers use for the gap made by Abelflex is an Isolation Joint. Check out the interactive illustration of some applications and products. The spacing of the joints can be varied slightly to make it more practical or for aesthetic appearance. This material acts as a shock absorber, absorbing the stress from the slab's movement. A concrete driveway may experience temperature differentials from 20 degrees below zero to … When to Saw-Cut Concrete . Expansion joints cut through the entire width of the slab and are then filled with some sort of filler. EMSEAL expansion joints and sealants seal the gaps throughout the building envelope. Joint spacing normally ranges between 10 to 18 feet depending on the amount of reinforcement the slab has. I agree with them...but theres a few things you need to know. Expansion Joint Wear and Damage. You can install concrete expansion joints before or after the concrete is laid. Regarding the type of structural expansion joint, the best expansion joint is to use a line of double columns to provide a complete separation in the building frame at the joints. Figure 1b: Joint Spacing in Feet Contraction joints may be tooled into the concrete surface at the time of placement. 2. Thankfully, there are few earthquakes in the UK, however, expansion joints are an important element in construction using concrete for all the other reasons. An expansion joint is a mid-structure separation designed to absorb vibration, join objects, or allow movement. Joints shall be spaced at 24 to 36 times the slab thickness but this need to be confirmed by a structural engineer. An expansion joint is commonly located on structures such as bridges, highways and sidewalks. Features: Resilient, flexible and nonextruded Long stretches of concrete do not require intermediate expansion joints. It's not that hard to do, you just have to be careful when you use a self-leveling caulking material, once you start the flow of the caulking it doesn't stop the instant you stop squeezing the lever. For sales quotes and orders please select from the following: Use our ready-mixed concrete calculator to select the best concrete for your project and work out the volume you require. I want to take the concrete right up to both. So, for a slab which is 100mm thick, the joints should be placed around 3,000mm (3 metres) apart. Installing expansion joints and using a high-quality silicone-based sealant is one important step you can take to ensure that your work will last for years to come. Cutting too early causes raveling, an effect created by the saw blade pulling the aggregate out of position, leaving a messy, weakened edge along the cut. To prevent cracks from forming, concrete expansion joints should be incorporated to allow for movement, particularly in slabs with a surface area exceeding 6m2. If you need to add an expansion joint to a driveway after it has been poured and has cured, you can use a cement saw to cut the joint. View Show abstract Expansion joints in concrete pavement are also seldom needed, since the contraction joints open enough (from drying shrinkage) to account for temperature expansion. It's not that hard to do, you just have to be careful when you use a self-leveling caulking material, once you start the flow of the caulking it doesn't stop the instant you stop squeezing the lever. Will the lack of an expansion joint hamper or destroy the function of the facility, or cause damage to the structural or architectural compo-nents? Expansion joints are put in place before the concrete is poured. Flexible concrete expansion joints may reduce crack formation. Road expansion joints are normally sealed with hot tar, cold sealant, or compression sealants. Movement joints are also useful when laying concrete within an area bounded by walls or buildings, or when an object such as a manhole cover has to be incorporated within the slab, as they allow the concrete to expand and/or contract without transferring pressure onto the other structures, causing cracks within the concrete slab, or the wall, MH cover, etc. © 2020 Growtivation. Alternatively, once the concrete has set, grooves can be cut in the concrete, this will control where the concrete will crack leaving a neat saw cut at the surface and allow joint materials to be added where required, but care must be taken to ensure the correct depth is achieved (see below). When working with concrete you should use fibreboard, which offers flexibility across the surface of concrete, allowing movement that will prevent cracking. Place joints around 30 times the slab thickness apart. Use a scraping tool, like a 5-in-1, to scrape out the old concrete expansion joint filler. Remember, any cracking can cause structural problems in your build. A tiled surface is similar to a sheet of glass in its rigid nature, and this can cause problems when there is movement. It will not deform, twist, or break with normal on-the-job handling. Keep Your Concrete Expansion Joint Watertight and Crack Resistant with Sikaflex Sealant. If you’re cutting joints after the concrete has been poured, don’t leave it too long. Filament tape can be placed over the expansion joint material prior to caulking. By placing expansion joints in a grid form across an expanse of concrete pouring, in positions where cracks can be expected to occur, cracks, if they occur, are held below the surface, remaining superficial and mostly invisible. If the expansion joint is being used externally (which is likely), ensure the joint sealant is suitable for external use. Concrete might crack if the joints aren’t cut within 12 hours after finishing. It is economical, long lasting and trouble-free. It forms a break between the concrete and other parts of a structure to allow movement without causing stress, which can lead to cracking. Features: Resilient, flexible and nonextruded They should be used in large concrete slabs such as foundations and concrete driveways. The function of the expansion joints is to endure the stresses produced due to temperature variations. It locks into concrete and adjusts for any slab movement. Vacuum out the concrete expansion joints. Please contact Cement.Technical.Help@Hanson.biz for assistance. The rugged life of a control joint As we know, control joints (more properly, according to the American Concrete Institute , contraction joints) are essentially planned cracks that allow for movements caused by temperature and moisture changes (drying shrinkage). In this video we demonstrate one of many ways to replace or fix expansion joints of concrete driveways / walkways / sidewalks. Use a scraping tool, like a 5-in-1, to scrape out the old concrete expansion joint filler. A concrete expansion joint – or control joint – is a gap which allows the concrete to expand and contract as/when the temperature changes. If expansion joints aren't installed, there's a risk of damage to the concrete or the structure the concrete parallels. The expansion joints are normally located between sections of bridges, paving slabs, railway tracks, and piping systems. They use a high-quality, self-leveling caulk that won't shrink and is flexible enough that it will remain in place even if the concrete does happen to shift around. There is also shrinkage after the concrete has hardened. All rights reserved. You’ll need them as rags (don’t whine about using your old Pink Floyd concert shirt, nobody thinks you’re cool if you wear it to the mall in 2000 whatever. Expansion joints in concrete – what you need to know, Building solutions – cracks in plaster, render, concrete and screed, Landscaping solutions – for sloping surfaces, Landscaping solutions: drainage and filtration, Landscaping solutions: ground stabilisation and soil separation, expansion joints are an important element in construction, SITEWORX Fibreboard Expansion Joint Filler, LWS Marketing : Website design, graphic design and marketing in Arundel, West Sussex. Joints are most effective when the aspect ratio of the slab is kept to 1:1, for example 5m x 5m if the slab is a narrower than it is long it is possible to increase this to a maximum aspect ratio of 1.5 for example 2m x 3m, don’t leave the placing of concrete expansion joints to chance and enlist the services of a structural engineer if several are required. How should you seal an expansion joint? Joints also let concrete shrink as it dries—preventing what's called internal restraint. When working with concrete you should use fibreboard, which offers flexibility across the surface of concrete, allowing movement that will prevent cracking. That was 15 years ago. Expansion joints are one of the important joints used in construction, like the roof expansion joints and in the paving slabs. Expansion joints are full-depth, full-width joints placed at regular intervals along the pavement, usually 50 to 500 ft (15 - 150 m) with contraction joints in between. Expansion joints separate the slab from structures such as foundation walls, footings, and structural support columns, and allow the slab to move unrestrained both horizontally and vertically.These joints can be strips of asphalt-impregnated sheeting, compressible foam, or other materials that are put in place before the slab is poured. Make sure you are cutting joints soon enough. Ideally, for expansion joints on the exterior of a st… How Often Do You Need Expansion Joints? An expansion joint that can add flexibility and buffer the movement in the concrete is therefore the best solution. From the ground to the roof there is an EMSEAL product available to handle your needs. In the first instance, a flexible material is inserted along the length of the joint before the concrete is poured [link to how to lay a concrete slab]. A light hose down keeps it bright and clean. SITEWORX Fibreboard Expansion Joint Filler comes in strips ranging from 100 to 200 mm wide or as whole sheets, in 12 or 19mm thicknesses. They are commonly found between sections of buildings, bridges, sidewalks, railway tracks, piping systems, ships, and other structures. Joint spacing that is greater than 15 feet require the use of load transfer devices (dowels or diamond plates). To fully understand the life-cycle impact of polyurea joint fillers, let’s first look at the life of a concrete control joint. When to use an expansion joint, how many and what expansion joint type to use is determined by the piping layout and the operating parameters.Also the connected equipment is determining when to use an expansion joint. Expansion joints allow space in which concrete can contract and expand without causing cracks. Also, if placed against inflexible materials, concrete has nowhere to go when or if it expands due to heat and moisture, again potentially damaging the concrete. In addition, these joints are constructed by interlocking the metal edges. I made a short video to show you how to caulk a concrete expansion joint. Most A-1 Concrete Leveling locations offer concrete joint and crack caulking. The Primer-3 N come in 1 Litre bottles – you should be able to prime around 40m of joints … WHEN TO CUT CONTROL JOINTS. Vacuum out the concrete expansion joints. Plan ahead: information you need at hand when ordering concrete, Hot rolled asphalt and pre-coated chippings, Laying a Long-Lasting Concrete Garage Floor, Mini mix/small ready-mixed concrete loads, Hanson terms and conditions of use policy. The expansion joint needs to be cut down a minimum of a 1/4″ below the concrete surface. DECK-O-JOINT resists acids, alkali, chlorine, etc. If you need to add an expansion joint to a driveway after it has been poured and has cured, you can use a cement saw to cut the joint. Expansion joints allows for movement without damage to the concrete. Let me introduce joints: All materials, including concrete expand or contract with the increase or decrease in temperatures. Improperly sealed expansion joints can sometimes be to blame, which is why it is so important to use a proper expansion joint filler for concrete when doing repairs. Having the floor joints in place helps create a weakened area in the concrete slab, since cracks follow the path of least resistance. However, this also means tensile pressure is put through the concrete as it shrinks, which can cause cracks. Restoring Concrete Expansion Joints the Hard Way. The pre-planned cracks will provide a better finish concrete product and will be formed in specific locations where those cracks could be monitored. The exception might be where a pavement or parking lot are next to a bridge or building—then we simply use a slightly wider isolation joint (maybe ¾ inch instead of ½ inch). Isolation and expansion joints in concrete pavements By James W. Mack Improper use of expansion joints can lead to pavement failure and high construction and maintenance costs When to Use Expansion Joints In most street and highway pavements, expansion joints should not be used. I wasn't planning to put anything between the pad and the block wall Now, I'm pretty sure I should put down expansion joints … Home » News » Expansion joints in concrete – what you need to know. This will ensure that the caulking does not stick to the expansion joint preventing three sided adhesion. You’ll find everything you need to know in our easy-to-use guide. Serving The Needs Of The Concrete Construction Industry, Since 1926. Use A Concrete Saw. Expansion joints are provided in slabs, pavements, buildings, bridges, sidewalks, railway tracks, piping systems, ships, and other structures. How to caulk a concrete expansion joint. Joints are most effective when the aspect ratio of the slab is kept to 1:1, for example 5m x 5m if the slab is a narrower than it is long it is possible to increase this to a maximum aspect ratio of 1.5 for example 2m x 3m, don’t leave the placing of concrete expansion joints to chance and enlist the services of a structural engineer if several are required. Expansion joints should be positioned in a vertical position along the edge of the driveway where the drive abuts the brick of a garden or house wall. The Expansion Joints are installed at set locations to assist with the creation of a weakened plane where the concrete material is … Minimize Concrete Cracking And Damage With Expansion Joints from W. R. Meadows. Find out more about the Growtivation Product That Works range by downloading our Product Guide and your free copy of our Landscaping That Works guide. Expansion joints are usually a complete 'gap' between adjacent bays, ie, there is a definite break in the concrete and any reinforcing steel that may be present. Utilising Expansion Joints or Control Joints as they are also known, is the most common method for controlling cracking when joining concrete slabs. If in doubt, call on the services of an expert structural engineer. These joint are placed where a slab meets a building, where a slab meets another slab, and where a pool deck meets the coping. It is composed of cellular fibers securely bonded together and uniformly saturated with asphalt to assure longevity. AS important is the basis of what you use to reinforce and support the pouring. Concrete isolation joints, or expansion joints, separate or isolate the concrete from other parts of the building structure like walls, footings, columns and piers. For tips on this, check out Bob Harris's video or get a copy of his Guide to Stamped Concrete-joints are covered in Chapter 23. There are two types of expansion joint filler, foam and fibreboard. However, joints need to be filled with soft, pliable material so that rainwater can’t get under the concrete, which could cause the construction to sink or heave. I made a short video to show you how to caulk a concrete expansion joint. As with wood, concrete can expand and shrink in heat. DECK-O-JOINT will not whip or warp during application. It's important to install concrete expansion joints on stationary objects the concrete is up against. - allow expansion AND contraction of a concrete slab without generating potentially damaging forces within the slab itself or the surrounding structures.