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Foundation waterproofing should always be undertaken during initial construction. It is nearly impossible to apply basement waterproofing products once backfill, where sediment is deposited around the foundation, takes place. Before discussing the proper basement waterproofing products to use during construction, however, it is important to make the distinction between waterproofing and dampproofing a foundation. Dampproofing, which is less expensive, was used frequently in the past to prevent moisture from reaching subterranean walls. In fact, it was often referred to as “waterproofing” until the two terms were officially codified in the International Residential Code. We will address the difference in greater detail in future articles, but the bottom-line is that dampproofing merely prevents moisture from soaking into below-grade structures. Dampproofing will not prevent damage due to hydrostatic pressure or protect against a large buildup of water against a foundation wall. You can find more information on the benefits of waterproofing products here.

Once you have settled on basement waterproofing, you will begin to assemble your basement waterproofing system. We call it a waterproofing system because it utilizes three elements: a waterproofing membrane, drainage tile a drainage board. These pieces compliment each other and work together to ensure basements remain water-free for many many years. In fact, Mar–flex offers a limited lifetime warranty on waterproofing systems combining our top-of-the-line green waterproofing products, the FUSION UV waterproofing membrane and Shockwave drainage board. The waterproofing membrane goes on first and is sprayed directly on the exterior of the below-grade structure. This will prevent water from reaching the concrete and contains a large enough polymer concentration to resist hydrostatic pressure by stretching without breakage. The drainage board will prevent water from building up around the structure by helping it to quickly flow away from walls. It is applied over the waterproofing membrane and protects the membrane from soil and debris while channeling away moisture that causes pressure to build up.  The drainage tile fits beneath the structure and channels water away from the floor in much the same way that drainage boards channel water away from below-grade walls. By pairing a true waterproofing membrane with a high-quality drainage board, you can ensure your foundation walls will be built to last.

Owning and maintaining a building is a constant battle against water intrusion. Whether through leaky roofs, broken window seals or foundation cracks, homeowners, tenants and contractors are always looking for solutions to keep the water out.

Concrete foundations are built for their durability, but despite their solid-seeming appearance, concrete foundation walls are very water permeable. Diffusion is slow, but anyone who has ever been in an unsealed basement knows the smell of mold and mildew growth that comes with gradual moisture intrusion.

Foundation waterproofing sealing is a critical component of constructing and maintaining a building’s foundation. A high-quality waterproofing system not only provides a membrane to keep liquid water out but also keeps water vapor out as well. Whether you’re building a new foundation or repairing an existing one, choosing the right foundation waterproofing will extend the building’s longevity and reduce long-term maintenance costs.

Talking to Homeowners About Foundation Waterproofing Sealing

Getting a homeowner to commit to resealing a foundation can be a task, especially if the work involves exposing the exterior foundation, which is an expensive undertaking. Often, homeowners may incorrectly believe their foundation has already been waterproofed when, in fact, they have only been dampproofed, which is the minimum code requirement in many jurisdictions.

During heavy rain events, water can infiltrate through solid concrete. Many building owners will wait for visible foundation cracks and water accumulation before calling a contractor. By helping them understand the other signs of moisture intrusion, you may be able to solve larger problems, like mold growth and foundational deterioration, before they happen.

Signs to look out for include:

• Staining on drywall
• Peeling paint
• Bowing or warping of panels
• Damp spots in carpeting
• White spots on walls
• Musty odors

If building owners are aware of these other signs of water damage, they can be more proactive in beginning repairs. Hidden moisture infiltration can damage electrical panels and appliances, cause chronic health problems, and potentially hurt property values, so addressing them quickly is of the utmost importance.

What Waterproofing Products Do You Need?

Foundation waterproofing sealers can be applied on the exterior of the foundation, which is recommended since it keeps water out of the foundation, while interior sealing won’t prevent future cracking and degradation.

Mastic can be applied in localized areas to patch joints, seams and visible cracks. Choosing a foundation waterproofing sealer that is a heavy duty, elastomeric emulsion will help prevent moisture intrusion.

When specifying a waterproofing product, make sure to check whether it is rated for waterproofness or dampproofness. A comprehensive waterproofing system will help keep water out during heavy rain events or spring thaws, while dampproofing will limit moisture intrusion from surrounding soil and groundwater.

A product like Mar-flex’s 362 All Season Mastic is a great choice for patching cracks and sealing foundation joints and seams before waterproofing. It can be applied by hand or with a trowel and leaves a flexible waterproof coating able to handle freeze-thaw cycles throughout the seasons. This flexibility also means that 362 Mastic can be applied at any time of the year.

For broader surface application, Mar-flex 5000 is a heavy duty, solvent-based or water-based polymer-emulsion blend that penetrates concrete or masonry to provide long-term residential waterproofing protection. Drainage boards are also available to extend the residential warranty for new construction applications.

Applying Foundation Waterproofing

Before applying the foundation waterproofing sealer, make sure to address any significant sources of water. These could include overflowing downspouts, improperly graded landscaping, or sunken paths and walkways that lead to water accumulation. It’s important to remediate these issues before installing a waterproof membrane in order to ensure its effectiveness.

Next, make sure your surface is clean and dry. Concrete needs to be free of loose particles as well as oils and greases to make sure your foundation waterproofing sealer adheres properly. If you’re waterproofing a new foundation, make sure the concrete has had enough time to cure or that you select a waterproofing membrane that is compatible with green concrete, such as the Mar-flex 5000.

Once you’ve addressed any exterior issues and prepared your surface, you are ready to begin installing the waterproofing system. Make sure you communicate important information like curing times and any warranty requirements to homeowners so that the project only needs to be done once, as re-excavation will be costly.

For more information on how to choose and apply one of Mar-flex’s foundation waterproofing products, visit our website.

Insulation is one of the most complicated choices builders and architects face during construction. Interior insulation is cost effective, but can reduce usable space and doesn’t protect against water. Exterior insulation is expensive and susceptible to insects. Regardless of the insulation choice, efficiency, toxicity and resiliency must all be taken into account as well. The Mar-flex team has put together a quick “cheat sheet” to outline the differences, advantages and disadvantages of each type of insulation.

ADVANTAGES of insulation on the EXTERIOR of basement walls:

• Minimizes thermal bridging and reducing heat loss through the foundation

• Protects the waterproofing membrane from damage during backfilling

• Serves as a capillary break to moisture intrusion

• Protects the foundation from the effects of the freeze-thaw cycle

• Reduces the potential for condensation on surfaces in the basement

• Conserves indoor space, relative to installing insulation on the interior

DISADVANTAGES of insulation on the EXTERIOR of basement walls:

• Costs may be high depending on materials and approach selected

• Expensive for an existing building unless a perimeter drainage system is being installed at the same time

• May be susceptible to insect infestation, however Mar-flex offers insect resistant materials

• Contractors may be unfamiliar with proper detailing procedures that are critical to performance

• Buildings with high radon will need a radon mitigations system to use exterior insulation

ADVANTAGES of insulation on the INTERIOR of basement walls:

• Interior insulation is much less expensive to install than exterior insulation for existing buildings

• Almost any insulation type can be used, however rigid foam EPS is recommended

• The space is isolated from the colder earth more effectively than when using external methods

DISADVANTAGES of insulation on the INTERIOR of basement walls:

• Many types require a fire-rated covering because they may release toxic gases when ignited

• Reduces your usable interior space by a few inches

• Doesn’t protect the waterproofing coating like exterior insulation

• May become damp if perimeter drainage is poor

• Did you know that there is a significant difference between waterproofing and dampproofing? Dampproofing simply slows down water penetration, but will not completely waterproof your foundation. Dampproofing, however, does protect against water vapor transmission. For the value based homeowner, dampproofing is an alternative to waterproofing, usually done with an easy to spray-on membrane, which dries into a seamless coating. Mar-Flex’s DampFusion Water Based acrylic dampproofing membrane is an economical solution to many damp basement or foundation issues. Value priced for the everyday consumer.

We talk a lot about the importance of proper basement waterproofing, but not everyone understands the subject as well as our team of Division 7 experts. Preventing water from damaging foundations is what we think about all day long. It is our business after all, and we consider it the most important factor a property owner should consider.

You don’t have to take our word for it, however. A team of home inspectors from Charlotte recently put together this video which does a great job explaining the importance of proper foundation waterproofing and the risks water poses to below-grade structures.

Mar–flex is not associated with Carolina Home Inspectors. We simply found their video to be an excellent educational resource. Of course, the home they were inspecting faced a very specific set of waterproofing challenges. There are, however, some things that all homeowners should be aware of regarding basement waterproofing. Chief among these is the importance of combining a waterproofing membrane with a drainage board and drainage tiles. We refer to this as a “waterproofing system.” Click here to learn more about how these elements work together to preserve below-grade structures.

Whenever a city experiences rapid growth, a building boom is front and center to accommodate all the new professionals coming to town. Welcome to Charlotte, largest city of North Carolina, and home to a growing business hub.

According to Forbes magazine, Charlotte is now the second largest banking center in the United States, only behind New York. Couple that with affordable housing compared to other U.S. metro areas, and Charlotte is an obvious choice for young professionals looking to start their careers—thus leading to an increase in new businesses and homebuilding.

Although Charlotte enjoys a mild, temperate climate year-round, dampness and moisture do not discriminate. These are real problems that threaten the strength and safety of a home or business workplace.

Enter the waterproofing membrane. A simple yet significant solution that can protect a building from the elements and provide the owner with peace of mind. Quality can range with these products, but it’s best not to skimp when battling the destructive capabilities of water and the damage it can cause.

Take for example Mar-flex 5000, a product designed to be applied to any wall foundation, with configurations of water-based or solvent-based. This industry-leading waterproofing technology comes at an affordable price and is produced in an environmentally-friendly manner, as it contains 20% recycled content.

Here’s how it works:

When water reaches the Mar-flex 5000 barrier, the heavy duty, elastomeric emulsion waterproofing membrane wicks away the water and moisture. There is a built-in resistance to freeze/thaw cycles, and it remains flexible because of a polymer concentration within. This delivers a rubber-fortified waterproofing product with decreased permeability and increased durability.

Mar-flex 5000 has been tested and proven effective with nearly every clean, dry and sound substrate. The solvent-based option can be applied in air temperatures as low as 0°F. Its special formulation sprays easily and predictably, producing a viscous, flexible, seamless seal.

Mar-flex 5000 is available in commercial and residential configurations, and both benefit from being paired with other components of a water protection system. Combining the Mar-flex 5000 membrane with an approved Mar-flex drainage board delivers the highest level of protection, and qualifies the product for a limited warranty.

Contact the professionals at Mar-flex to talk over how we can protect your home or place of work. We can discuss a set of solutions that are right for you and designed to help ensure a long life for the structure. Get in touch to discover the protection you need for your home or business.