Stucco & Concrete Repair
Today’s concrete buildings deteriorate. They deteriorate for a variety of reasons. Many of which are avoidable. But when these conditions exist, the painting contractor should be, prepared to, and experienced in, making the repairs needed.
Understanding the different deck systems and methodologies to repair them is a must for a remedial contractor. The contractor must; have the craftsmen talented enough to execute the repair so it is not noticeable when the work is complete; be able to make the repair properly so it does not fail; be able to provide to the customer, the reason for the failure and the required course of action to prevent it’s reoccurrence.
Glendale has made these repairs on many properties over the years. The repairs are not as prevalent as they once were since proper education has removed many of the avoidable circumstances that used to cause the problems (carpeting on decks, etc).
Here is some general information about concrete, repairs and methods available:
Concrete & Stucco
The keys to concrete repair include removing all deteriorated concrete, exposing corroded re-inforcing steel, surface prep of exposed steel and concrete, proper treatment of the bond lines, and application of an appropriate patching material with similar properties to the original concrete.
Concrete Repair
Concrete is a very versatile building material which requires reinforcement such as cables or rebar to help it support great loads or span distances thus structural concrete. Reinforced concrete structures generally have good life expectancy. Concrete still requires maintenance because deterioration does still occur. The most common causes of deterioration are caused by corrosion of reinforcement steel by water and salt (or other corrosive) migration and freeze thaw cycling or the combination of both.
Concrete Delaminations
Concrete can delaminate in layers which are most commonly caused by the expansion created by corrosion of internal reinforcement. Locating or detecting these delaminations can commonly be determined by non destructive testing, such as, chain dragging the surface. The extent of deterioration in the delamination is often unknown until the delamination is opened up. Locating and properly repairing concrete delamination is one of many types of repairs CDC does.
Spalled Surfaces
Spalling of the concrete surface is where the concrete topping is popping or peeling off. Common causes for this action is a weak top surface, rounded aggregates, overworking the concrete, low air entrainment, excessive water, freeze thaw cycling and more. Repairs that can be done include: installing a topping (or overlay) which can be cementitious, polymer, epoxy or elastomeric. In some cases the use of a special grinding machine may resolve the problem.
Repair Deteriorated Concrete
Concrete floors that have eroded due to chemical attack or abrasion can be easily repaired to bring them back to close to their original elevations. Resinous materials offer a very quick turnaround time in that they cure quickly and a new protective floor coating material can be applied as soon as the materials cure which can be in as little as 45 minutes. Materials that are cement based can also be used which are less expensive, but generally need a longer cure time, especially if the thickness is greater than ½ inch. Cementitious materials will also need to have their surfaces prepared by mechanical means prior to applying a new flooring system, whereas resinous systems will not need this procedure. Most cementitious materials have limitations of needing to be a minimum of ¼ inch in thickness, thus they cannot be feather edged like a resinous material can be.
Balcony Repair
Repair of balconies can include concrete repair, railing removal/reinstallation or replacement, deck coatings, replacement of caulk and repair of adjacent brick, dryvit or other exterior wall finishes. Two issues are unique to balconies.
The first is the extreme proximity to the owner's living quarters. With all of the potential activities listed above taking place within feet of the living quarters, a consistent systemic approach to these repairs is critical to the success of the project.
The second is the connection of a thin slab of concrete to a typically metal railing. The connection detail, typically embedment with grout, is the most common area for deterioration of concrete to start. Modifying these details as part of the repair has over the years lead to longer term repairs.
Epoxy/Chemical Injection
Concrete cracks. No one likes it, but it is a fact. These cracks create structural concerns and waterproofing issues.
Chemical injection is used for stopping water penetration through cracks in concrete walls and slabs. The most common use is for walls or slabs with soil on the opposite side of the wall or slab from the leak. The removal and replacement of soil to install a membrane is prohibitively costly. There are many types of chemicals that have been developed for these uses. Most use an activator to expand the gel once in the crack in the concrete. Expansion of 300 per cent by volume is possible with current technology.
Epoxy Injection addresses the structural concerns by acting as a glue-like substance in the crack. This is commonly used in structures that incurred a onetime loading or movement event. This type of repair will not be effective in areas of repetitive thermal movement induced cracks.
Epoxy Injection
Utilized most commonly for bonding concrete, wood and or steel surfaces together (Concrete Welding). Epoxy injection is utilized when concrete requires the need to be bonded together, most times when movement is determined to not be taking place.
Urethane Injection
Urethanes formulated for injection are most often more flexible than epoxies. Urethanes can more often be utilized when movement is suspected. Waterproofing cracks, filling voids, stabilization, blind side waterproofing are the advantages and some uses of urethane injection. Most times is not considered a structural repair.