EPI Painting is one of the leading waterproofing companies in Gainesville, FL and Jacksonville, FL. We provide high-quality waterproofing systems to protect your business. Waterproofing protects the surface of your property or structure from water damage, difficult weather, mildew, and other environmental conditions. Our professional team manages different types of sealants and coatings that help prevent premature aging of commercial and industrial buildings.
We work with:
- Liquid-applied waterproofing
- Sheet-applied waterproofing
- Cementitious waterproofing
Using sealants (caulking) is more prevalent now that façade construction has changed and expanded, as well as the fact that new cladding materials are now available.
Typical Applications that Require Sealants
- Joints that go between concrete, metal cladding panels, or stone veneer
- Masonry expansion, coping joints, and stone-to-flashing points
- Joints at the door and window perimeters, as well as glass or glazing perimeters
- Joints in a horizontal surface, such as terraces or plazas
Most of the joints used are simple butt joints, but specialty joints have been developed for newer applications, which include lap joints, fillet joints, glazing heel beads, and regular glazing beads.
Most of the high-performance sealants that are used today include polyurethane and silicone. However, some older buildings might use acrylic, polysulfide, oil-based compounds, or butyl.
Signs of a Sealant Failure
There are four primary conditions that usually determine sealant failure. These include:
- Adhesion/bond of your sealant to your substrate
- Cohesion/internal integrity of your sealant
A loss of adhesion can result in the separation of your sealant from its substrate, which is sometimes visible in the openings along both sides of the joint. Cohesion loss is usually seen with cracks that run parallel to the joint’s interface. Elasticity loss can contribute to both cohesive and adhesive failures, which is indicated when the sealant cannot recover after a deformation or by a hardening of the material. Weathering can be indicated by discoloration, chalking, wrinkling, random/alligator cracking, excessive softening, or erosion of the sealant surface.
Factors contributing to these failures can include improper sealant use or improper joint design. Sealant characteristics must also be considered when selecting the right sealant and designing the width of the joint, such as elongation, elasticity, and substrate movement expectations.
Proper sealant selection is essential and should be evaluated to ensure that the substrate is compatible with the sealant. If the substrate does vary on the joint sides, different preparations may be necessary for each of the sides.
Improper Sealant Installation
If the sealant isn’t installed correctly, failure could result. Sealants are usually installed with a polyethylene bond-breaking tape or a compressible foam backing rod. Other means are available to ensure that the sealant doesn’t adhere to the joint back. If the sealant does get stick to the joint’s back and the sides, it won’t contract or expand without ripping or tearing.
Temperature is also important for when installing the sealant. If the ambient temperature is too low (below 45 degrees Fahrenheit), the joint could already be at the widest dimension possible. In this case, the sealant can’t accommodate the cyclic expansions for the substrate or compress the joint when heated. Lower temperatures can retard the sealant cure, as well. Plus, if the sealant is installed during extreme cold temperatures (below freezing), surface contamination because of frost could result in improper bonding.
Conversely, if the temperature is too high (above 90 degrees Fahrenheit), the joints may be too narrow, and the sealant may not be able to accommodate the cyclic joint expansion. If installed during very hot temperatures, sealant might flow. This instance can happen more frequently in locations that have direct sunlight or with darker colored sealant. In some cases, polyurethane sealants can reduce durability if they are cured in high temperatures.
Types of Sealants
Many sealant types can’t bond with other sealants. For example, anything other than silicone sealants usually can’t provide a durable enough bond with other silicone. However, silicone might not cure correctly if installed along with isobutylene sealants, so it is best to avoid installing sealants over current sealants. Instead, you should remove the current sealant and reseal it.
Sealants often can’t bond to fluoropolymer-based finishes without using a primer first. Solvent-based sealants that are put over a thermoplastic sealant could dissolve the sealant or soften it, which cause a partial failure at the substrate/paint interface. Light-colored sealants shouldn’t be applied on neoprene gaskets because the gasket oil could stain the sealant or might stain the substrate.
Urethanes can be one-component (such as moisture curing) or two component options based on reactions between the hydroxyl and isocyanate components. They’re usually chosen to seal high-movement joints and porous surfaces. Urethanes usually allow for 25 percent movement capabilities and are usually the preferred choice for cladding joints.
If you cure the urethanes at high temperatures (120 degrees Fahrenheit), it could cause it to degrade prematurely in ultraviolet lighting, which can lead to severe reversion. Dark-colored substrates that are exposed to sunlight during temperatures of 80-90 degrees Fahrenheit could reach a temperature of over 160 degrees Fahrenheit. When some urethanes are cured at these temperatures, they might appear to cure regularly but they could start flowing or become bubbled/gummy if they are continuously exposed to ultraviolet light or heat.
Urethanes with one component can cure when they react to moisture in the air. Some urethanes use moisture scavengers, including calcium oxide, which can inhibit the set until the right placement happens. If the particles of the scavenger used are too big or exposed to the surface, they might react with rainwater, which can cause staining on glass and frames.
Most of the problems relating to multi-component urethanes result from improper mixing. When the mixing is incomplete, sealant portions are going to remain uncured or fluid. Incomplete curing can happen when you use outdated materials or because they were formulated incorrectly.
Silicone sealants focus on alternating the silicon-oxygen atoms. Many field-applied silicone products are one-component styles. Some are cured with acid (acetoxy) and some are cured with alcohol (neutral). Acid-cured silicone shouldn’t be used on acid-sensitive products, such as marble, limestone, or masonry. Silicone sealants are usually used on non-porous surfaces with high-movement joints and capability ranges of -50 to 100+ percent. Applications can include metal or glass substrates, and cladding joints that don’t have to deal with staining issues.
Silicone sealants tend to stain frequently, which is a common issue. Staining is noticed by an accumulation of dirt on the sealant or by the migration of a sealant plasticizer into your adjacent substrate. Some of the substrates used are significantly vulnerable to staining and migration when using silicone sealants. Any silicone sealant that is installed on glazing could adhere poorly if the surface of the glass is contaminated.
Silicone sealants can also fail if the water gets behind any sealant in the open-cell backer rod. Most silicones don’t have the best long-term adhesion when placed in standing water or frequently wet. Testing must be done in dry and wet conditions.
Other Types of Sealants
Polysulfide sealants use polymers that contain sulfur and usually have a sulfide odor characteristic added. Older polysulfide sealants use PCBs to plasticize them, which are now considered possibly carcinogenic.
Polysulfide sealants are usually only used in cladding joints, though they can be used in joints that are going to be submerged.
Acrylic sealants use thermoplastic resins that are formed when the esters of acrylic acid are polymerized. They provide more limited movement capabilities and stronger adhesion characteristics. Usually, they are used in small-scale construction for low-movement joint needs.
Latex, Butadiene, Styrene, Acrylic Terpolymers
These sealant types use rubber resin colloidal suspension, either natural or synthetic, and in water. Some of these sealants are modified using small amounts of silicone. Like the acrylic compounds, they have a more limited movement capability and are usually used for small-scale construction projects and low-movement joint needs.
Polyisobutylene sealants are based on the petroleum hydrocarbons and are non-elasticized glazing materials. They are used primarily for splice seals in window frames, glazing joints, and seals for insulating glass units.
Sealers and Coatings
Concrete and masonry brick are some of the most durable components for building. However, the materials can deteriorate throughout time if they aren’t maintained properly, even in the southern regent’s weather conditions. In our experience, sealers and coatings can be some of the most effective ways to protect concrete and brick structures from weather elements.
Clear coatings are state-of-the-art and based on silane, silicone or siloxane compounds that penetrate masonry and brick surfaces. They are available in matte and gloss finishes, and they are intended to provide more long-term protection to concrete and brick surfaces.
More Advanced Coating Technologies
Newer technology has allowed penetrating coating compound options to be created, which replace older film-forming products for concrete and brick structures. When they are applied correctly, these more advanced coatings can be highly effective in prolonging weather deterioration.
Modern pigmented sealers and coatings use advanced elastrometric or water-based acrylic materials. They’re available in many colors and the pigmented emulsions can penetrate any masonry surface to change it to the right color.
Sealers and Coatings Prevent Water Damages
Sealing concrete and brick walls prevents water from penetrating the junctures that are exposed to severe weather conditions. Exterior sealers and masonry coatings are designed to repel water but not be waterproof. Nevertheless, if they are applied correctly, the compounds can change the capillary angles of the pores in the brick masonry wall from suction (positive) to repellency (negative). In some cases, sealers and coatings can fill or bridge hairline cracks and separations in masonry wall faces and offer some protection from freeze/thaw cycles.
The surface protection offered for newly placed concrete and brick significantly influences the longevity of the product. Unprotected patches can allow moisture to come into the structure at the edge of the patch or through any shrinkage cracks.
Most coating materials can be applied using spray, roller, or brush. Before you apply the coating, you must ensure that the wall is clean because heavy atmospheric dirt accumulation can interfere with the adhesion or penetration of the coating, which can result in a shorter lifespan and poor performance. It is essential to test the chosen sealer or coating on a wall section that is scheduled for treatment. Make sure that the test area is 10 feet square, at least.
You should also check moisture content in the wall at multiple locations and observe all climatic conditions to ensure consistency according to the manufacturer’s recommendations.
Selecting a Sealer or Coating
Choose a sealer or coating that is produced by a manufacturer who is well known and has a good track record. Make sure that you get references for similar projects and demand that they provide test reports for any relevant criteria. You should also request a written warranty from the manufacturer.
You should also check the qualifications of the contractor applying the product and ensure that the contractor protects any surrounding or adjacent surfaces to prevent overspray.