Tips for Selecting the Right Repair Material
Selecting repair materials is a decision that must go beyond the initial purchase price. While manufacturers have developed repair products covering a wide range of working properties and bonding characteristics, this decision can still be very difficult.
On many small projects, the choice of repair materials is often left up to the contractor. It can be easy to opt for a repair material product that has worked well on a previous project. But jobsites, types of concrete, and conditions can differ significantly, so be open to alternative materials that can help you complete the job faster.
On larger projects, a design professional may specify the materials in the contract documents. Even so, you often have the option to substitute to a “similar” product. This is the time to be very careful. A less expensive material may have many of the same attributes as the specified material, but it only takes one misjudgment and you’ll be owning the project.
Your White Cap repair professional can help you evaluate the choices that exist between material types.
Another important factor to keep in mind is that a good repair material has minimal shrinkage. The host concrete has already gone through its shrinkage, so if the repair material shrinks, it could debond, and the repair will fail.
There are basic repair material types designed for typical uses.
The most basic repair materials available are cementitious patching compounds. All you need to do is add the required amount of water to these one-part, normal-setting products.
Many product manufacturers have modified these basic materials to enhance plastic qualities and increase durability. These one-component, or two-component, polymer-modified cementitious repair mortars are available in pre-proportioned kits for easier mixing and application.
Polymer concretes and mortars represent another category of repair products. These are not cement-based, but rather thermosetting plastic materials, such as epoxies, polyesters, vinyl esters, and methyl methacrylates, usually with aggregate fillers. Epoxies and other polymer mortars offer high strength, durability, and chemical resistance. They work well in small angular spaces around rebar and in narrow cracks, but they can’t be used to fill large cracks and holes.
Epoxies will also weaken or burn when exposed to heat, so they can’t be used for structural repairs without additional fire protection.
Your White Cap professionals can cover all these repair options and help you secure the right materials that conform to even the most demanding job specifications.
On many small projects, the choice of repair materials is often left up to the contractor. It can be easy to opt for a repair material product that has worked well on a previous project. But jobsites, types of concrete, and conditions can differ significantly, so be open to alternative materials that can help you complete the job faster.
On larger projects, a design professional may specify the materials in the contract documents. Even so, you often have the option to substitute to a “similar” product. This is the time to be very careful. A less expensive material may have many of the same attributes as the specified material, but it only takes one misjudgment and you’ll be owning the project.
Your White Cap repair professional can help you evaluate the choices that exist between material types.
Factors When Making Your Repair Material Choice
Purchasing repair material requires close attention to some important factors.1. Expected Service Life
Not all repairs are designed to stand the test of time. Owners often request stopgap measures designed to prevent further damage until a more complete repair can be undertaken. With the proper surface prep, patching materials are a cost-effective option.
On the other hand, many repairs are undertaken to extend the structure’s service life beyond its original design. These projects often require custom made formulations. Check in with your White Cap repair specialists when purchasing materials. You might want to consider asking the manufacturer to include an integral color tint to help match the repair’s appearance to the host concrete.
2. Amount of Material Needed
When purchasing repair material, it’s important to select the packaging size that matches the site conditions, mixing options, and manpower. Many interior projects have limited access, so select a sack weight and transportation mode for maximum ergonomic movement. Most manufacturers offer several bag sizes, and in some cases supersacks.
On many projects, you’ll be also purchasing caulks and sealants. Be sure to opt for the packaging that matches the amount of work. Sausage tubes and buckets are always more economical than cartridges.
Also try to plan your purchase to ensure that all the materials received on site have the same lot number. This will help you simplify any product testing reporting requirements that reside in the project documents.
3. Repair Orientation
Match the material’s physical characteristics to the repair area’s orientation. Manufacturers can provide material compositions designed specifically for horizontal, vertical, and overhead installations. You can also opt for material flow characteristics that are either poured or pumped into large or hard-to-access voids.
4. Primer is Critical
Primer is an important piece to any repair. Many skip this step or minimize the need for a primer. Please make sure you understand your repair material and use the correct primer, applied correctly, to get a successful repair.
5. Return to Service
Ask your client to tell you how quickly you are to release the project to their use. You can often shorten the cure period by opting for an appropriate material that will quickly achieve its full strength. In addition to the material selection, you may need to consider curing blankets or heaters to hasten hardening.
6. Strength Requirements
Materials can be formulated to meet different strength requirements. When the repair will be placed under a load, compressive strength is important. For pavements and floors, a material’s flexural strength can be an important criterion. And in some situations, strength to resist abrasion and wear is important.
The repair material must also match the host area’s characteristics. If the repaired area will be under load, the elastic modulus should be similar. Thermal coefficients (the rate at which the material expands or contracts with temperature) should also be similar, or the repair bond can weaken and separate over time.
Not all repairs are designed to stand the test of time. Owners often request stopgap measures designed to prevent further damage until a more complete repair can be undertaken. With the proper surface prep, patching materials are a cost-effective option.
On the other hand, many repairs are undertaken to extend the structure’s service life beyond its original design. These projects often require custom made formulations. Check in with your White Cap repair specialists when purchasing materials. You might want to consider asking the manufacturer to include an integral color tint to help match the repair’s appearance to the host concrete.
2. Amount of Material Needed
When purchasing repair material, it’s important to select the packaging size that matches the site conditions, mixing options, and manpower. Many interior projects have limited access, so select a sack weight and transportation mode for maximum ergonomic movement. Most manufacturers offer several bag sizes, and in some cases supersacks.
On many projects, you’ll be also purchasing caulks and sealants. Be sure to opt for the packaging that matches the amount of work. Sausage tubes and buckets are always more economical than cartridges.
Also try to plan your purchase to ensure that all the materials received on site have the same lot number. This will help you simplify any product testing reporting requirements that reside in the project documents.
3. Repair Orientation
Match the material’s physical characteristics to the repair area’s orientation. Manufacturers can provide material compositions designed specifically for horizontal, vertical, and overhead installations. You can also opt for material flow characteristics that are either poured or pumped into large or hard-to-access voids.
4. Primer is Critical
Primer is an important piece to any repair. Many skip this step or minimize the need for a primer. Please make sure you understand your repair material and use the correct primer, applied correctly, to get a successful repair.
5. Return to Service
Ask your client to tell you how quickly you are to release the project to their use. You can often shorten the cure period by opting for an appropriate material that will quickly achieve its full strength. In addition to the material selection, you may need to consider curing blankets or heaters to hasten hardening.
6. Strength Requirements
Materials can be formulated to meet different strength requirements. When the repair will be placed under a load, compressive strength is important. For pavements and floors, a material’s flexural strength can be an important criterion. And in some situations, strength to resist abrasion and wear is important.
The repair material must also match the host area’s characteristics. If the repaired area will be under load, the elastic modulus should be similar. Thermal coefficients (the rate at which the material expands or contracts with temperature) should also be similar, or the repair bond can weaken and separate over time.
The Importance of Bonding
While the specific requirements will vary from one project to another, your goal is to create a strong bond between the repair and the host material. The repair material should be similar to the substrate in terms of its stiffness or flexibility (modulus of elasticity), its thermal expansion properties, water absorption, and water vapor diffusion.Another important factor to keep in mind is that a good repair material has minimal shrinkage. The host concrete has already gone through its shrinkage, so if the repair material shrinks, it could debond, and the repair will fail.
Classifying Repair Materials
Choosing from among hundreds of repair materials is a daunting task. When undertaking extensive full-depth repairs and reconstruction projects, you’ll want to select a mix that matches the original concrete as closely as possible.There are basic repair material types designed for typical uses.
The most basic repair materials available are cementitious patching compounds. All you need to do is add the required amount of water to these one-part, normal-setting products.
Many product manufacturers have modified these basic materials to enhance plastic qualities and increase durability. These one-component, or two-component, polymer-modified cementitious repair mortars are available in pre-proportioned kits for easier mixing and application.
Polymer concretes and mortars represent another category of repair products. These are not cement-based, but rather thermosetting plastic materials, such as epoxies, polyesters, vinyl esters, and methyl methacrylates, usually with aggregate fillers. Epoxies and other polymer mortars offer high strength, durability, and chemical resistance. They work well in small angular spaces around rebar and in narrow cracks, but they can’t be used to fill large cracks and holes.
Epoxies will also weaken or burn when exposed to heat, so they can’t be used for structural repairs without additional fire protection.
Purchase Materials from a Reliable Source
With so many options for repair materials, manufacturers provide options that conform to specific characteristics based on ASTM test procedures. These standards include setting time, flow, compressive strength, flexural strength, split tensile strength, bond strength, drying shrinkage, freeze-thaw resistance, and permeability.Your White Cap professionals can cover all these repair options and help you secure the right materials that conform to even the most demanding job specifications.