APPLY a masonry waterproofing product to the bare interior walls of the basement. If the foil test showed that water penetrates through the basement walls and leaves them damp, seal the inside of the walls with high-quality waterproof paint, such as DRYLOK White Extreme waterproofing agent (available at Home Depot). Use putty to seal doors, windows and window openings. We recommend an elastic sealant such as Big Stretch Sealant or Lexel Sealant, which are waterproof and flexible.
The “wrapping” principle can also be applied to keeping a basement dry. A very effective method of waterproofing basements is to “wrap a basement, fully or partially, with an outer waterproofing membrane”. Of course, such a membrane is created by coating a wall with asphalt modified viscous polyurethane and not covering it with laminated products, but when the membrane cures it forms an envelope on the outside anyway. If you are going to waterproof walls that have been previously painted, you must first remove old paint or other coatings.
DRYLOK transparent masonry waterproofing agent is an excellent product that is guaranteed to protect walls and floors against hydrostatic pressure and water filtration. These masonry waterproofing products are applied to basement walls to prevent moisture from seeping in. Many of the waterproofing products listed below will only work if applied directly to the substrate, so if there is any existing coating on the surface, wall, or floor, it must be removed. While there are many methods that can be used, a popular method is to apply an impermeable coating to walls, which will create a barrier that will prevent water from seeping in.
Waterproofing a base from the outside generally involves the use of polymers and membranes to coat the outside of walls, the installation of an underground trench drain, or a combination of both methods. This is called efflorescence and must be removed before waterproofing to ensure proper adhesion of the waterproofing paint. An exterior waterproofing job usually costs much more than an interior waterproofing job because the job requires heavy equipment, more labor, and takes longer to complete. Hydraulic cement and putty are popular options for DIY attempts to waterproof a basement from the inside.
Waterproofing a basement from the inside is usually the best option for most homes, mainly because it's more cost-effective and less harmful than outdoor excavation. Of course, interior drain tiles won't do much good without a proper sump pump, so let's talk about the workhorse of any basement waterproofing system. If your plans - at least for now - are simply to clean the basement and prevent future flooding, all you need to do is waterproof. There are a variety of reasons for basement water seeping, leaks, flooding, and humidity; some are easy to fix and others require the help of a professional who specializes in basement waterproofing.