The Importance of Building Sealant

Building Sealant

The Importance of Building Sealant

Building Sealant is an essential component of a structure as it helps in closing the gaps and holes between materials and mechanical joints to prevent fluids or other substances from passing through them.

Various sealant technologies come with different performance capabilities, therefore it is important to choose the right one for the application.

Sealing Joints

Sealants are used to seal joints between various materials in a building. There are many types of sealants and they vary in their properties and performance. Some are flexible and can expand or contract to accommodate different movement. Others are rigid and have limited ability to move.

When a sealant is chosen, it should be based on the intended use of the joint and the expected environmental conditions. These conditions can include temperature, moisture and UV rays.

The performance of a sealant depends on a number of factors including the joint design, the installation method and the adhesion to the substrates. It also depends on the chemical and physical properties of the sealant.

One of the most important factors in selecting a sealant is its ability to withstand joint movement. If a sealant is not designed for the anticipated movement, or if it is installed incorrectly, then the sealant will have problems with adhesive or cohesive failure.

A sealant may also not be able to resist movement because the joint opening width is too small. This can cause the sealant to crack or sag.

There are several standard test methods for determining sealant durability and this is a good place to start when looking for a sealant that will withstand the type of movement anticipated on a job.

This is done using ASTM C719 where the sealant joints are put in a compression machine and moved back and forth for 10 cycles. When the sealant reaches the compression limit it is removed from the compression machine, allowed to cool and then placed in an extension machine that moves it at 1/8 inch per hour until it reaches its maximum planned extension.

When this happens it is examined for adhesive and cohesive failure along with other flaws such as dirt pickup, crazing and cracking. This can take a long time and the damage will vary from job to job.

These tests can help a specifier determine whether or not a particular sealant will meet the expectations of a building owner and architect. However, they are not an exact science and the longevity of the sealant is still an unknown.


When it comes to waterproofing your home or building, there are a few different materials that can be used. Each material requires a specific type of sealing to protect it from water. These sealants are usually referred to as waterproofing chemicals and can be applied to wood, concrete, bricks or other materials that can be exposed to moisture.

Some sealants are better suited to certain types of materials than others. This depends on the type of material, the amount of traffic that it will receive and the climate in which it is being constructed.

For example, wood needs a different type of waterproofing chemical than concrete or bricks, as the former are more porous than the latter. In addition, the density of the material may also play a role in the choice of waterproofing sealant.

One of the most common waterproofing methods is called joint sealing. These sealants are usually non-shrinking or expanding and they help to prevent moisture from entering the joints, which can lead to serious issues if not addressed.

Another common method of waterproofing joints is injection. This involves supplying waterproofing material to the seams, under pressure and using equipment, through a packer or pre-prepared tubes inside the concrete. This is especially effective when there are hollows or micro cracks in the concrete.

The choice of the right waterproofing method can be tricky, but it is essential to get the right solution for your building’s needs. It’s important to consider the type of concrete that is used, the age of the structure Building Sealant and where it is located so that a professional can recommend the best waterproofing method for your project.

Other factors to keep in mind include the thickness of the waterproofing material, the water absorption rate and how flexible it is. The waterproofing material must have a uniform thickness and have good elasticity to resist differential movement that can cause cracks.

The type of waterproofing material you use can make a difference in how long it will last, the quality of the building and even if you need to repair the surface again later on. It is a wise idea to use the best waterproofing material for the job at hand, and it’s not uncommon for buildings to need a re-sealing after a few years of deterioration due to exposure to moisture.

Sealing Cracks

Cracks in concrete foundation walls and slabs can be a sign of structural problems. Sealing them can help protect the structure from further damage and ensure that water cannot seep into the foundation.

There are many different types of building sealants available, ranging from traditional bitumen or tar products to specialized epoxy sealants. Each type of product has its own strengths and limitations and must be tested before being used in a construction project.

These tests can provide the information needed to determine whether the sealant is suitable for a particular job and if so, what the best product is to use. Some test methods are commonplace, such as ASTM C794 or ANSI B16.5 while others may be more specific to the application.

The most important aspect of these tests is to determine the ability of Building Sealant a sealant to resist movement in a joint. This is especially important for expansion joints, which must be able to accommodate a percentage of vertical displacement. In addition, a sealant must be able to hold up under compression without losing adhesion or starting a tear.

Several different types of building sealants can be used for sealing cracks in concrete, each with its own unique advantages. Some of these include flexibility, elasticity and water resistance.

One type of crack sealant is a flexible, elastomeric bond. It is composed of a polymer and a rubber compound that can deform under stress but recover when the pressure is removed.

Another type of crack sealant is a polyurethane foam that expands inside the crack, filling it and protecting the concrete from further damage. These types of crack sealants are commonly injected using a low-pressure injection system.

Some cracks are too fine to be sealed with a conventional epoxy preparation, but they can still be sealed with an expanding polyurethane foam. This method can be more cost effective per linear foot than an epoxy sealant and will often repair the crack.

Both methods will require a number of injection ports along the crack to allow the sealant to be injected into the concrete. The plastic injection ports should be lined up with the crack to allow the sealant to be applied into the crack and will need to be tapped in place partway through the crack with 3 inch (10d) finishing nails.


Building sealants are an important part of the building envelope and must be inspected on a regular basis. Failure to do so can lead to leaking walls, discoloration of the facade, mold and other issues.

Often, maintenance crews are distracted by other building repairs and overlook sealing joints, causing them to be compromised. If left unchecked, these deficiencies can result in the need for a full facade restoration, which is expensive and disruptive to the building.

While inspections are critical for preventing these problems, they must be conducted in accordance with established maintenance guidelines. A building owner or facility manager should have a written maintenance manual that outlines the necessary inspections, repairs and corrective measures. This documentation should include an inventory of materials and equipment and a list of current maintenance needs, including inspections.

It is also vital to conduct laboratory testing on sealing joints to ensure they can handle the joint movement. This can include a test procedure that involves exposing the joint to continuous compression and extension (see ASTM C1589), as well as back-and-forth testing at temperatures. This process examines the joint for adhesive and cohesive failures, cracking, crazing, dirt pickup and other defects that could affect the performance of the sealant.

In some cases, the plasticizer chemical within the sealant can migrate from the bead and react with surrounding material to form stains and streaking that make the joint appear bad. It is possible to avoid this problem by asking the manufacturer to try a lab test to determine a sealant’s propensity to stain.

Once the appropriate maintenance procedures are in place, buildings can be properly maintained and will not require full facade restorations for years to come. The cost of the initial inspection and repair is minimal compared to the costs of a full restoration, but it can be costly to replace the structure later.

Building sealant joints are an overlooked area of the building envelope and a major cause of leaking and water infiltration. Proper inspection and maintenance of the building’s sealants will reduce the need for costly repairs and can save money over time.