Concrete Balcony

How do you repair a concrete balcony?

Balconies are not accessible for year-round enjoyment like they are in some warmer areas of the world, so when they can be enjoyed, you want to make the most out of them. A long period without use can lead to signs of damage being overlooked. Take some time to periodically check in on your concrete balcony year-round and note any changes or deterioration. Signs of trouble include rust stains, cracks on the deck, peeling coatings, peeling paint, sealant failure, and loose or broken railings.

Strength, durability and longevity make concrete a common choice for balconies. Over time, however, wear and tear, lack of maintenance, improper installation or exposure to the elements leave the balcony walls or floor appearing rough, cracked or bumpy. Cracks in the concrete not only mar its appearance but also serve as a structural hazard if left to spread. In general, you should monitor any crack for six months to ensure it does not increase in size. While you can fix small or hairline cracks yourself, ask a structural engineer to inspect the balcony if the crack is deep or large and determine its root cause.

High rise balcony concrete repair due to water damage is a growing issue and usually means using suspended access to conduct the repairs. From my experience, the rain that falls on the concrete balconies normally pools by the doors. The outer edge of the balcony is also generally in bad condition due amount of water it is in contact with. When the damage gets too bad, then a concrete repair contractor is called in to do the concrete restoration and provide concrete solutions for that particular project. The concrete repair depends on what the engineer has marked out and the amount of meters he is allowed to work with. Of course, this can change depending on if serious issues need to be addressed. Sometimes the work is done to sell the building and other times because it is in dire need of repair. In either case, an experienced concrete contractor can correct it.

Check out Hitch Property Constructions for a wide range of balcony repairs.

Common Causes of Concrete Balcony Deterioration

Wondering what caused your balcony to crumble, crack, or peel? A professional assessment may be required to identify the exact issue, but there are some common causes that our contractors encounter when it comes to balcony deterioration. These are the usual culprits that, thankfully, are avoidable:

Concrete Balcony


If the slab tops and sides of your balcony are not treated or waterproofed correctly, it can lead to a much shorter lifespan. Without waterproofing, concrete can be more vulnerable to damages from moisture, freezing, and thawing.

Deck tiles, carpets, and other ground coverings can improve the appearance of your balcony and help to create a more welcoming outdoor living space. They can also cause damage if the slab underneath these coverings is not appropriately waterproofed.


Joint areas where the balcony meets your home or building and where railing posts attach need to be sealed with extra attention and care. The adjoining materials are more exposed and are prone to damages if the proper sealant is not used. It is a good idea to ‘touch up’ these areas from time to time.


Rebar that has rusted, become exposed, or is near the top of the surface of the balcony can cause issues and lead to faster deterioration.


Cracks or voids should be sealed as soon as you notice them in the balcony slab. If left unattended, they will expand more quickly and can lead to structural issues. Even if the crack seems small, it should be addressed before it can progress.

Accessing the Balcony Concrete Repair

Concrete repair – swing stage. A common way to access these concrete repair jobs on High Rises is to use suspended access equipment. These are called swing stages that have motors that operate on suspension lines that are rigged to the top of the building. In this scenario, we might want to support the upper floors where the beams are resting for our stage with jacks for extra support.

The Process for Concrete Repair on a High Rise Balcony

Concrete repair on a balcony – cutting the edge for chipping. Concrete repair on a balcony – chipping away the bad concrete. First, we remove all the balcony railings with a STIHL Metal Saw and chipping hammer for railing feet to be able to access the balconies. When looking to mark the concrete balcony repair that will be needed to show to the engineer, we use marking spray, chain and a hammer. The chain and hammer are used to sound out the concrete. This will show delaminations with dull, hollow or flakey sounds indicate delaminated areas and concrete to be removed.

Concrete repair on a high rise apartment building – swing stage access. Once we have each balcony marked out on the drop the stage is located, we start to remove the concrete. A good option here is to have a hoist available to load the rubble into so as not to put too much weight on the stage. We also will attach mesh around the stage to catch debris and mesh that we can sport to the lower floor to catch when chipping the edge of the balcony.

High rise balcony repair, detail of exposed rebar after the cut. Concrete repair on high rise balcony – exposed rebar on edges. We use a Stihl 420 Concrete saw here after snapping our chalk line for the outer edge of the balcony. With the large blade, the cuts are straight and fast. We are just cutting into the concrete here to give us clean edges for the final pour rather than chipped jagged edges. All the rebar exposed must have any additional concrete knocked off with a hammer and examined. Tying in new rebar where necessary and doweling in rebar if needed. We chip under the two layers of rebar with a fingers gap on the bottom rebar in centre slab cuts for the concrete to hold. All the rebar is then wire wheeled with a grinder and/or coated to protect.

Preparing for the pour on the concrete repair

Plywood forms are created to pin bolt into a place of the voids along the edge of the balcony and for any through slab voids that were created. For the outer edge forms, we use trim on the underside for a drip edge for the water to run off. We use the Bosch Bulldog Max Hammer Drill to create the pilot holes for our pin bolts used to secure our forms to the existing concrete slab. We then would use jacks on each floor to secure and adjust our final form and to create a tight seal. The least amount of pin bolts we used the easier to release the forms at the end of the pour.

When doing the concrete pour, we used a hoist. The guys would be dropped off on several floors with their finishing tools and a bucket of water/concrete mix to wet the voids. A hose would be attached to the stage also for water on the floors. When the truck loaded up our hopper, it would be sent up to the appropriate floor and pulled in and lowered on the existing balcony. Here it would be shovelled and loaded into the forms. After the pour has been completed and finished, we come to remove the forms and cup grinding the repaired concrete surface for a nice even finish.

Balcony Survey

The first step is to hire a qualified engineer or architect to conduct a thorough survey. Working from a scaffold to fully access all the balcony areas, the engineer/architect will select an apartment line with balconies that show obvious signs of deterioration. Using a mallet to sound out the concrete, the engineer/architect will determine which areas are the most badly damaged and if the balconies are still structurally sound. Another sign to look for is ponding water, which indicates the balcony is not correctly sloped, preventing proper drainage.

Loose railings are a safety hazard and a code violation.

As part of the survey, the engineer/architect may request investigative probes of the concrete (conducted by a contractor) to determine underlying conditions. In some cases, the engineer/architect may determine that a core sample—an approximately 4-inch-wide circular cut through the entire thickness of the concrete—needs to be taken. The core sample will be tested to determine the compressive strength of the concrete; it will also show the extent of damage through the entire thickness of the concrete slab. Investigative probes will determine if the steel reinforcement is rusted, which could lead to structural weakness. Keep in mind that to fully view the balconies’ surfaces and conduct the probes, the carpeting, and any other type of coverage as well as the aluminium cladding will have to be removed.

Based on the survey findings, the engineer/architect will recommend whether a full-scale repair program is needed or if limited repairs will suffice. In your building’s case, a balcony repair program would probably entail extensive concrete repairs and the installation of new railings. If the balconies are extremely damaged, they may need to be completely demolished and rebuilt.

Looking for balcony repairs Melbourne? Look no further. Hitch Property Constructions has you covered.

Concrete Repairs

While financially strapped boards may be tempted to hire a contractor to make spot repairs such as patching and caulking, the underlying deterioration in the concrete will remain and only grow worse. To properly repair the concrete, the defective areas must be entirely cut away. The cuts should be straight, not bevelled or tapered, and the cut surfaces must then be scarified—i.e., given a rough texture by mechanical means—and a bonding agent applied, so the new concrete properly adheres to old. If missing, a drip edge—a narrow groove several inches from the edge on the balcony’s underside, extending the length of the balcony—should be made to help direct dripping water away from the building.

Carpeting traps water on balconies, deteriorating the concrete.

After the concrete repairs are made, a non-slip traffic-bearing coating system should be applied to the balcony floor and curb surfaces. A non-permeable coating system is applied to the balcony fascia surfaces. In contrast, a permeable coating is applied to the underside so the surface can breathe and allow water vapour transmission. Coating systems come in a variety of colours.

Ironically, sometimes repairing the concrete balcony floors and applying a coating system increases ponding. Two factors cause a paradox. First, water that used to enter through cracks in the concrete now stays on the surface because the cracks have been repaired and the non-permeable coating system prevents water from seeping in. Keeping water from penetrating the concrete is desirable, of course, and the point of making repairs. The second factor, however, is if the balcony is not properly pitched toward the drain (usually located near the balcony door), water pools in depressions in the balcony surface. The remedy requires the application of a new layer of tapered concrete to attain the correct slope so that water properly drains.

Aluminum Cladding

Cladding is sometimes installed on new balcony curbs as an added protection or deteriorated concrete curbs in a misguided attempt to prevent further water infiltration. In some cases, aluminium cladding is even used to hold crumbling concrete pieces together. At best, the aluminium only temporarily blocks water. The cladding typically loosens over time, allowing more water in and trapping it, causing significant damage to the underlying concrete. Once repairs are made, the balcony edges should be left exposed.


Loose, rusted railings should be repaired or replaced depending on the severity of the deterioration. Railing posts will have to be removed from the concrete, and the defective concrete surrounding it cut away. It is recommended that the posts be inserted into stainless steel sleeves or sleeve openings that are then filled with epoxy. Sometimes a cushioned filler called a backer rod, which is topped off with caulking at the base of the post penetration into the concrete is used to keep water out.

If you’re replacing the entire railing system, you may want to consider aluminium instead of metal. With a proper finish, aluminium does not rust and therefore requires far less maintenance than metal since it does not need to be regularly scraped, primed, and painted. New York City Building Code requires railings to be at least 42 inches above the finished surface on the balcony. If a layer of concrete has to be added to the balcony to achieve the proper slope for drainage (as described above), the new layer may reduce the height between the top of the railing and the balcony surface. The engineer/architect should account for this height difference when specifying the repair scope and railing design.

Maintenance requirements for the new balconies should be minimal.

Since the building will be undertaking a facade restoration program, it makes sense to incorporate the balcony work as part of the overall repair program to avoid paying twice for mobilization and scaffold costs. The contractor will likely work on one apartment line at a time, so the board should have adequate time to give residents notice to remove all items from their balconies, including furniture, planters, rugs, personal items, etc.

As part of the repair program, the contractor may need to file an ACP-5 form to confirm there is no asbestos-containing material in the railing’s paint or the balcony’s existing sealant or coating. You’ll also need a work permit from the New York City Departments of Buildings, as well as a permit from the Landmarks Preservation Commission if your building is located in a Historic District.


Once the new repairs are in place, maintenance of the new balconies should be minimal. The caulking around the railing posts should be periodically checked and re-caulked as needed to prevent water penetration. The balcony should be kept free of debris, and residents should take care not to drag furniture or sharp edges across balcony surfaces as this could scratch and compromise the coating system.

Finally, residents should not cover their balconies with any carpeting, which traps water and keeps the balcony surface constantly wet, accelerating deterioration. Carpeting also hide cracks and makes maintenance more difficult.

There’s no getting around it: A full-scale balcony repair program is a major undertaking, but it’s one that should not be ignored. To preserve the safety and enjoyment of residents, it should be approached with the same level of consideration as other large-scale exterior projects.

Repairing Concrete Floor

Step 1

Clean your concrete balcony floor using a pressure washer fitted with a fan tip. Hold the washer 8 inches above the concrete floor and move it in slow sweeps to remove accumulated dirt and debris, exposing the cracks.

Step 2

Fill cracks, holes and crevices on the floor with concrete repair caulk. Smooth out the top of the caulk with your finger. Allow the caulk to cure for the time specified on the label’s directions.

Step 3

Prepare concrete dressing according to the manufacturer’s directions in a 5-gallon bucket.

Step 4

Spread the prepared dressing over the balcony floor and immediately spread it out with a trowel, pressing it hard into tiny crevices. Assign a helper to quickly prepare another batch of concrete to pour around the remaining sections of the floor for a large balcony.

Step 5

Run a medium-bristle broom across the surface of the wet concrete to create a slip-proof surface. Allow the concrete to cure according to the time specified on the manufacturer’s directions.

Repairing Concrete Walls

Step 1

Rub the crack in the concrete wall with a stiff wire brush to remove loose pieces. Use a shop vacuum to remove accumulated debris. Ensure the crack is dry, or direct hot heat from a blow-dryer over the crack for 20 minutes if it is damp.

Step 2

Hammer 3-inch finishing nails every 12 inches along the length of the crack. Pound the nails halfway into the concrete wall.

Step 3

Prepare the two-part crack sealer according to label directions on a scrap board. Spread it over the base of the plastic port included in the repair kit. Slide the port over the nail, with the base touching the wall, until it covers the nails completely. Repeat this process to install the remaining ports along the crack.

Step 4

Spread the repair epoxy into and over the crack and extend it by 1 inch on each side. Pack the epoxy around each port’s base and flange. Do not cover the necks of the ports. Allow the epoxy to cure for the time specified on the label’s directions.

Step 5

Insert the tube of liquid epoxy provided with the repair kit into the caulk gun. Inject it into each port until excess epoxy begins to drip. Cap each port with a plastic plug. Allow the filler to cure for five days.

Hitch Property Constructions has a wide range of the Melbourne balcony repairs right here. 

Step 6

Cut the elongated necks of the plastic ports off with the hacksaw, until they are flush with the surrounding concrete wall.

Balcony repairs often begin by evaluating the repairs necessary for the concrete. Cracks in the concrete, even hairline cracks, of a balcony will prove to be problematic in the elements of the northeast. The first steps will be to investigate the causes of the deterioration to determine underlying conditions. Once the causes are determined, professionals will repair the concrete balcony and any accompanying balcony railings. The keys to concrete repair or balcony replacement include removing all deteriorated concrete and steel, exposing corroded reinforcing steel, surface prep of remaining exposed steel and concrete, and the application of an appropriate patching material with similar properties to the original concrete. The proper treatment of steel and concrete will ensure the longevity of your balcony restoration.

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