What Is Building Sealant?

Building Sealant is a substance used to seal or fill gaps and cracks between different types of building materials. It can also be used to block air, water, and other environmental elements from entering or exiting a structure.

There are many sealants on the market for use in construction. These include silicone, acrylic, urethane, butyl, and other polymer types. Each has its own properties and needs.

Sealing Joints

Sealants are used to seal joints in the building structure. These are commonly the joints between the different materials such as concrete, masonry, aluminum etc. These sealants are strong against stress and also have good bonding properties with the building material.

These sealing products are often called caulks, but they may be more appropriately termed sealants. They come in various types and are designed for a wide range of applications and construction types.

In order for a sealant to provide the required performance attributes, it must first be installed properly and in accordance with the manufacturer’s instructions and specifications. This includes a variety of factors including the application environment, access for the sealant applicator, and proper primer and joint filler application.

The installation of a sealant should not occur at an area where the substrates are experiencing movement that exceeds the design range of the sealant. This can be due to mechanical Building Sealant stressors (e.g., vibrations and radiation) or thermal variants such as seasonal climate changes or temperature fluctuations.

Typically, movement is measured in units of percentage of joint width (e.g., +100% / -100%) and the results should be compared to the performance criteria established in the specification or data sheet for that specific sealant. Some examples are ASTM C719.

For most, if not all sealants that meet this standard, movement will have no significant impact on adhesive or cohesive performance. However, if movement is to be an issue in the application then there must be some way to test for that ability under field conditions and have that data available to the specifier and applicator.

There are many standards that test for this, and most specify a set of tests with some combination of continuous or periodic joint movement to compress, then repeat 10 cycles. This is done to simulate the conditions that are seen in a variety of weathering environments.

Another test that will give a hint at how well a sealant can handle joint movement in the field is ASTM C1589 and Section 10.2. Procedure B (outdoor movement) and Procedure C (periodic manual extension and compression) are both good examples of this type of testing. The results from these test methods are not as accelerated as those from some other weathering and compression tests but still gives some indication of how long the sealant will perform in a particular climate.

Sealing Cracks

Sealants are a critical component of any building envelope. They provide waterproof, weatherproof, and abrasion resistant seals on all the joints that separate different materials within a structure. They can be used on many types of construction materials, including concrete, masonry, metal, wood, glass and fiberglass.

Sealant selection is made based on a number of characteristics. The most important are adhesive strength, cohesive strength, recovery ability after deformation, modulus and durability under the effects of weathering.

For example, if you are using an epoxy sealant to fill a crack, it needs to be able to bond well and not leak out of the crack when the concrete moves as the slab ages. Additionally, it should have the ability to remain flexible and withstand compression as the slab moves.

Likewise, if you are using a polyurethane crack sealant, it also needs to be able to accommodate movement. It can do this through either an internal flow under stress mechanism, which is known as cold flow or plastic flow, or by accommodating a tensile force.

Both of these mechanisms are necessary for a sealant to meet the requirements for sealing a control joint in a concrete slab. This sealant should be able to bond to the sides of the cut or opening of the joint, remain flexible over temperature and moisture changes and withstand both compression and expansion.

Special poly urea caulks designed as joint fillers are available that are injected into the crack to create an effective sealing joint that will accommodate any movement in the concrete. These injection caulks are often less expensive than their spray-on counterparts and work best for cracks that are too fine to inject a polyurethane foam sealant or too large to use an epoxy crack filler.

Regardless of the sealant method you choose, it’s vital to have an Environmental Product Declaration (EPD) prepared for your product before installation. This EPD will give you the information you need to make an informed decision about whether or not your building project will impact the environment.

Sealing Ductwork

When your ductwork is properly sealed, your air conditioner and heating system can operate more efficiently, saving you money on energy bills. Sealing ductwork also improves indoor air quality by keeping dust, pollen, and other particles from entering your home.

Even small leaks in ductwork can have a big impact on your air quality and overall health. The moisture that enters your ductwork can cause mold to grow, which may make you sick and negatively affect your home’s HVAC system.

Leaky ductwork can also contribute to higher utility costs because your air conditioning or heating system must work harder to maintain your desired temperature. You can save a lot of money on energy by sealing your ductwork and insulating it.

Several different techniques are available for sealing your ductwork. You can apply duct tape (the old-fashioned way) or use mastic and Aeroseal.

The old-fashioned approach involves using high-quality duct tape and mastic to seal all of the gaps and cracks in your ductwork. Mastic is a water-based, paste-like substance that hardens right after it is applied to the area where it is leaking or needing sealing.

When applying mastic, be sure to use an overlap of at least a 1/2-inch around any joint or crack in the ductwork. This is especially important if the joint or crack will be under stress.

Mastic is a good choice for sealing ductwork because it’s easy to apply and is more cost-effective than foil duct tape. It will also last for much longer than foil duct tape.

You can find mastic at any hardware store or home improvement supply Building Sealant store. It is a water-based, fiber-reinforced paste-like material that can be applied with a paintbrush or a caulking gun.

Another great option is Aeroseal, a liquid rubber sealant that can be used for sealing the ductwork from the inside out. This is a more complicated process than the DIY approach and will likely require the services of a professional.

Regardless of which method you choose, the key to success is finding and fixing your air leaks. If you don’t take care of them, your ductwork could deteriorate and lead to costly repairs down the road. This is why it’s so important to get regular inspections and have your ductwork professionally inspected for leaks.

Sealing Window Frames

Sealing window frames can help keep drafts out, reducing heating costs and increasing the comfort of your home. This can be done with a variety of products, including caulk, silicone sealant and air insulating foam.

Before applying any type of sealing product, you must first prepare the area. This includes removing any old caulk or other materials from the window frame. Clean the area thoroughly and let it dry. Use a brush or cloth to remove any dirt, grime and other debris that could inhibit the adhesive properties of the new sealant.

If the existing caulk is loose, you can also scrape it away with a steel putty knife. Doing so will ensure that your new sealant can adhere well to the window frame.

To get the best result, you should use a caulking gun with a thumb release to apply your sealant. Start at one end of the joint and move across it, using a consistent forty-five-degree angle. If you have to reapply, do so until the sealant is a smooth bead of liquid.

Once the cracks are fully sealed, the windows will be airtight and free of drafts. In addition, you may want to consider installing a draft stopper on the bottom sash of the window. You can buy these at your local hardware store or home improvement store.

Another way to seal windows is with a rubber gasket. These are made from an EPDM material that resembles backer rod and come in a variety of colors to match most building types. They can be installed on a wooden or aluminium frame.

The EPDM sealant can be trimmed to fit around shims, or you can use shim screws instead of wood shims. A rubber gasket is a cost-effective solution for sealing window frames.

A good alternative to a rubber gasket is butyl rubber, which is an expandable variety that can be applied over a wide range of materials. Its flexibility allows it to fill in gaps that are larger than a quarter of an inch, so it’s ideal for sealing areas like gutters and flashing options.