How to Finish the Basement and Avoid Water Problems

Basement renovation

Your basement provides the ideal area for casual living, an extra bedroom or another bathroom. But improper planning and poor construction may result in basement water problems that keep your family out of this valuable space. Finish the basement and avoid water problems with these handy tips and direction.

Fully Assess the Area Before Construction Begins

A basement renovation involves many stages. Assessment should be first on the list, and both the homeowner and contractor should carefully inspect the area for water damage and potential water problems. These issues may include:

  • Damp walls
  • Damp floors
  • Cracks in the foundation
  • Gaps in window frames or at the sill
  • Puddles
  • Poor grading around the foundation
  • Improperly sloped patios, driveways and decks

The Canadian Mortgage and Housing Corporation notes several questions you should ask in the planning stages of a basement renovation. Some of these questions refer to moisture in the lower level of your home, such as:

  • Do you see any evidence (sporadic or permanent) of moisture, mildew or mold on surfaces in the basement, such as floors, ceilings, framing or walls?
  • Do you detect a musty odor on any items stored in the basement or in the area itself?

For the full list of pre-basement renovation questions, click here.

What To Do After the Assessment

If any evidence of moisture or mold has been detected on any of the areas listed above, repairs must be your first priority. The repairs required depend on the location and amount of water damage or moisture.

Damp walls or floors, with no sign of standing water or puddles, are often a result of poor grading or a high water table. Concrete is naturally porous, and water coming into contact with the foundation will seep through. Avoid this problem by installing a sealant along the interior wall of your basement, or by applying a rubber barrier along the exterior of the foundation walls. Consider the costs and effectiveness of both methods before making a final decision.

Cracks in the foundation and gaps in window sills or framing require a more extensive repair. Certain contractors specialize in concrete crack repairs, and will assess the size and shape of the cracks before suggesting a permanent solution.

Always check the references of these contractors before hiring and be sure to obtain proof of the warranty.

Window Concerns

Window sill or frame repairs provide the opportunity to upgrade your basement windows. Consider installing energy efficient products, replacing rotten or damaged sills and even incorporating larger windows or patio doors into the space for additional natural light.

For small cracks and issues around your basement windows, good quality caulking or sealants may work. Speak to your contractor for details about your basement windows.

Properly installed window wells help to direct rain water and storm runoff away from your basement foundation. At least 6 to 8 inches of gravel should be laid at the bottom of the window well to help water drain away fast.

Set drainage tile or "big O" piping under that gravel and running to the foundation drain. This area of stone or gravel resting along the footing will quickly redirect water to the storm sewers or storm water management pond, and away from your basement.

The Importance of Good Grading

It may seem counterproductive to plan for your basement renovation by correcting your backyard (or front yard) grading. But remember that poor grading is one of the leading causes of basement water problems. And correcting that issue now could save you thousands of dollars in repairs and replacements in the future.

Several outdoor issues could cause water to flow into your basement, despite your best efforts to keep it out. A University of Tennessee source noted the following common sources:

  • Rain water - especially when gutters are not installed or existing gutters remain clogged or broken
  • Ground water - hydrostatic pressure from groundwater sources can force water through even the smallest cracks
  • Storm runoff - homes installed on a slope or those near springs or standing bodies of water are at risk of flooding during a spring thaw or particularly strong rain storm

Correct grading issues with additional clean fill or by repairing a patio, driveway or deck that slopes into, instead of away from, your house. Contact a landscape professional to assess the yard and listen to their suggestions. Corrections range from a simple re-grading project to more involved footing repairs or dry well installations.

Essential Inclusions

Some water problems are evident before your basement renovation begins. Others occur due to the design of the space. These latter problems can be avoided by including certain elements in your finished basement.

Talk to your contractor about installing this equipment in your basement:

  • Sump Pump - very important for many rural homes and those without a sanitation sewer nearby, a sump pump gathers water at the lowest point in your basement and then pumps it away. The sump pit also collects groundwater from the footing drain. Capped and fitted with a primary and backup pump, this pit and pump set up helps to redirect groundwater and avoid major flooding in your basement.
  • Floor Drain - for homes with a connection to sanitary sewers, a floor drain works to direct water away from the foundation. Ensure your basement floor drain has a "P" trap and always keep it topped up with water.
  • Backwater Valve - avoid the mess of sewage backups with a professionally installed backwater valve connected to all major plumbing fixtures in the basement.

Protect your renovation investment by planning the project well. Start with an assessment of the existing situation and correct any issues presented. Consider your windows and grading and ensure those key areas are designed to reduce the risk of flooding and water seepage. Finish your basement and avoid water problems with careful plans and the help of an experienced professional. The right design will help to create the ideal living space downstairs.

Posted by: TrustedPros
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