Important Steps of Preparation When Finishing a Basement

Basement renovation

Finishing a basement is an excellent and affordable way to add valuable living space, but without the right approach this project can become a nightmare. Find out what steps of preparation are required to make this space comfortable and safe for the long term.

Waterproofing the Basement

Water in the basement causes all kinds of problems, including mold and mildew growth and the deterioration of building materials. This can be an even larger problem in a finished basement, and homeowners should do everything they can to waterproof the basement before the renovation project begins.

Research the various ways to keep water out of the lower level, including these popular methods:

  • Subfloor and baseboard drain systems - these systems are incorporated either below the basement slab (subfloor) or along the baseboards (baseboard). Used in conjunction with a sump pit, drainage systems will capture and redirect water that enters your basement. They will not keep water out.
  • Negative-side sealant - paint or apply this product directly onto the interior walls of your basement foundation. Often oil-based, you may be able to find a latex product that emits less odor while providing the same sealant qualities.
  • Exterior grading and drainage systems - consider working with your landscaper to enhance the grading around your foundation. French drains can also be added to the yard to redirect standing water and rain, reducing the risk of basement flooding.
  • Waterproof membrane - applied to the exterior wall of your foundation, membranes provide excellent protection from below-grade basement flooding, although they cannot protect against water flowing through or around windows, doors and other entrances.

Repairing the Foundation

Foundation cracks are common, especially on homes that are constructed during the winter months. Cracks in the floor or walls of your concrete foundation will allow water to seep into this space. Vapor barriers and negative-side sealants cannot prevent this occurrence, but you can take steps to fill these cracks before any of the insulation or wall framing goes up.

Fast setting hydraulic cement makes this a straightforward DIY project. Available at your local hardware store or building materials retailer, this product is inexpensive and relatively effective for small or moderately sized cracks.

You must chip out the cracks to a certain size for hydraulic cement to work properly. Once the space has been cleared, the cement is sprayed down to encourage bonding. With a putty knife and a steady hand, hydraulic cement is applied directly into the cracks and smoothed off at the surface. Within a day or so your basement walls and flooring are well protected from seepage. Cracks may continue to form, and a good quality negative-side sealant should be applied for added protection.

Rod holes also need to be filled or patched before finishing the basement. These holes are formed during the initial construction of your home, but the material used to originally plug them degrades with time and creates a gap for moisture to enter your basement. Re-plug rod holes with hydraulic cement and regain your solid foundation.

Installing a Sump Pump System

If your home is not currently equipped with a sump pump system, consider having this installed before finishing a basement. Sump pits take up space and a portion of your basement will need to be left unfinished to accommodate this system. But without a sump pump, rain water, high water tables and spring runoff can result in serious damage to your new basement.

Have a local contractor assess the area and install the pit and pump system. A large drain pipe will run between the pit and storm sewer, and may require extensive excavation. Sump pump systems work well with other basement waterproofing methods and are vital during an actual flood, moving water out of your basement and reducing damage to the area.

Floor Preparation

It may be a good idea to level your subfloor, no matter what type of flooring will be installed. A new plywood subfloor with shims provides a level base for underlayment and carpet, laminate or engineered hardwood. Ceramic tile also works well in the basement, and requires a level foundation for a durable finish.

Use floor levelling compound to prep a concrete subfloor. Quality brands come in a dry mixture, which is designed to self-level when added to water and spread onto your existing subfloor. Along with a closed cell underlayment, many durable types of flooring can be installed on your level concrete subfloor.

Consider whether or not to include radiant underfloor heating in your new basement living space. These systems provide an unmatched warmth that welcomes you all winter long. Perfect for the bathroom and the main living space, underfloor heating systems must be designed, prepped and installed in the initial stages of your basement renovation.

Electrical and Plumbing Design

Another step of preparation you cannot do without is the design of your electrical and plumbing systems. Are you considering a home theatre system in the basement? Do you want a fully equipped bathroom on this level? Think long and hard about this space and draw out a plan of all electrical and plumbing systems.

Your electrician and plumber can use this design as a basis for more detailed wiring and plumbing layouts. Creating these designs also helps you to hammer out what you want in real space, and plan room dimensions and features to scale.

Remember to include all of the things you want in the basement now, and those you wish to install in the future. Planning for and installing at least a portion of these items now will save you time and money later on. Roughed in bathrooms and rough wiring cut down on expenses and labor later on.

Finishing a basement takes careful planning and careful steps of preparation. Ensure that your finished basement is done well by considering ways to waterproof the basement, as well as patching cracks and holes in the foundation, levelling the subfloor and designing your plumbing and electrical systems. Taking these steps will save you money and result in more comfortable, valuable living space downstairs.

Posted by: TrustedPros
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