A wet basement is a common and frustrating problem for homeowners, often stemming from its below-grade position that makes it susceptible to moisture and water damage. Understanding the root causes is the first step towards effective waterproofing.
Common Reasons for a Damp Basement:
- Foundation Cracks: These are direct pathways for water to seep through basement walls and floors as the house’s foundation shifts and settles over time.
- Unsealed Openings: Basement doors, windows, egress windows, and window wells that are not properly sealed provide easy access points for water.
- Inadequate Drainage: This is a significant cause where rainwater is not effectively directed away from the home. Water that sits around the foundation will eventually seep into the basement. This can be due to:
- A poorly designed or installed drainage system.
- Clogged or improperly installed/maintained gutters that overflow.
- Improper Landscaping Slope: If the ground around your house slopes towards the foundation, water will run directly to and accumulate around it.
- High Water Table: In some areas, the natural water level in the ground is consistently high, leading to constant hydrostatic pressure against basement walls and floors.
Ring’s End Guide for DIY Interior Basement Waterproofing
Ring’s End offers products for basement waterproofing, and while serious issues may require a professional, many interior waterproofing tasks can be handled by a DIYer.
Before You Begin
Crucial Prep: Before applying any waterproofing product, ensure the area is completely dry, and all standing water is removed. Many products only work when applied directly to the substrate, meaning any existing coatings (like old paint) must be removed.
- Removing Old Paint/Coatings: Use a wire brush, sandblaster, or other appropriate methods. Always wear proper protective gear. Contact a Paint Center for advice on safe removal.
- Cleaning Walls: Wash walls with a scrub brush and warm water with a little dish soap to remove dirt and dust.
- Mold Removal: If mold is present, add 1 cup of bleach per gallon of water to your cleaning solution. Crucially, never mix bleach with products containing ammonia.
- Efflorescence Removal: If you see white, powdery, crystal-like deposits on masonry walls (efflorescence), it must be removed. Use DRYLOK Concrete and Masonry Liquid Etch & Cleaner or muriatic acid, following manufacturer’s directions carefully.
- Drying: Let all cleaned areas dry thoroughly before proceeding.
5 Steps to Interior Waterproofing Your Basement Walls and Basement Floor:
Step 1: Clean the Area
(Repeat of the “Before You Begin” cleaning instructions for emphasis on its importance.) Thoroughly clean walls of dirt, dust, and any existing coatings. Address mold and efflorescence as described above, and ensure the area is completely dry.
Step 2: Plug Holes
For any visible holes and large cracks, use hydraulic cement like DRYLOK Fast Plug. This material sets and hardens very quickly (3-5 minutes), even under pressure, so have a plan ready. Use a trowel to smooth the cement before it sets.
Step 3: Fill Cracks
Fill smaller cracks with a Masonry Crack Filler.
Step 4: Seal Openings
Use caulk to seal around doors, windows, and window wells. Recommended products are flexible, waterproof sealants such as Big Stretch Sealant or Lexel Sealant.
Step 5: Apply Waterproof Coating
Once all holes and cracks are sealed, and surfaces are dry, apply a waterproof coating to your basement walls and floors.
- DRYLOK Clear Masonry Waterproofer: An excellent choice, guaranteed to protect against hydrostatic pressure and water seepage. It can be used on both walls and floors.
- DRYLOK Masonry Waterproofer (White/Gray): These tinted versions are available but are only for walls, not floors.
- Application: Apply with a quality nylon bristle brush or a ¾” nap roller, working the product into the masonry’s pores.
- Coverage & Warranty: Proper coverage and a minimum of two coats are required for warranty waterproofing. Always read all manufacturer guidelines and instructions before applying.
- PRO TIP: To prevent water from migrating through the seam where the wall meets the floor, tape along the concrete floor one inch out from the base of the wall. Paint the DRYLOK on the walls, along this seam, and onto the floor up to the tape line.
Basement Waterproofing Tips:
- Remove Standing Water First: Never attempt crack repair or sealing until all standing water is completely removed from your basement floor.
- Use a Dehumidifier: Run a dehumidifier in your basement to reduce condensation, which helps prevent mildew and mold growth.
- Check Dryer Venting: Ensure your basement dryer is correctly hooked up to its vent, with no air leaks around the hose. Improper venting releases hot, moist air that can cause condensation.
- Insulate Sweating Pipes: Condensation can form on cold pipes. Insulate them to prevent this “sweating.”
- Painting Over DRYLOK: You can paint over DRYLOK Waterproofer. Use a waterproof paint suitable for high-humidity environments, such as Benjamin Moore Aura Bath & Spa.
Exterior Waterproofing (When to Call a Professional):
While interior fixes are homeowner-friendly, exterior waterproofing is a much larger undertaking.
- Professional Consultation: For serious cracks, significant concrete wall deficiencies, or groundwater pooling around your house, it’s recommended to hire a contractor or a landscape architect/civil engineer for a consultation. They can advise on extensive foundational damage repair, yard regrading, or redesigning the drainage system.
- DIY Exterior Fixes: Before resorting to excavation, some easy DIY exterior steps include:
- Strategic Planting: Avoid planting flower beds or bushes that require frequent watering too close to your house.
- Gutter Maintenance: Ensure gutters are clear and properly flowing to direct water away from the house. Consider installing gutter guards.
- Re-leveling Slabs: If walkways or patios slope towards your house, consider re-leveling them to drain away from the foundation.
Preparing for Basement Floods:
- Sump Pump: If your house is in an area with a high water table, some basement flooding during heavy rainstorms may be inevitable. A sump pump is a crucial addition to a waterproofing system. It can be installed either above or (more commonly) submerged below the basement floor, pumping and discharging water from inside the basement to the outside.
Crawl Space Waterproofing:
- If your house has a basement crawl space, it is equally important to seal the interior and exterior walls of the crawl space to prevent water seepage.
When to Call a Professional Basement Waterproofing Company:
If you are uncertain about the extent of the damage or whether you can effectively resolve the water problems yourself, calling a professional waterproofing expert is advisable for peace of mind.
- Many waterproofing service companies offer free inspections to assess the damage and provide estimates for repair services.
- If professionals identify extensive basement leaks that have caused major structural damage or if your basement requires significant foundation repair, it is strongly recommended to have them handle the work.