Basement design and planning

Do you need a basement in your home, or would you like to renovate or repair your current basement? In some areas, they serve as storm shelters and are essential elements for safety and security. Basements also provide an escape from outside noise and tend to stay a constant temperature and require less heating or cooling. Basements introduce a whole different set of challenges than above ground structures and those challenges need to be considered when designing your basement.


Because basements are structures that are beneath the surface, moisture from runoff, condensation or seepage through the soil becomes an issue in basements. These moisture issues need to be dealt with when designing your basement. Here are a few tips to help:

  • Make sure that there is a good slope away from the foundation wall of your home so that runoff gets away from the wall. 2” fall for every foot of run is necessary.
  • Make sure that downspouts empty well away from the foundation wall. 3 to 5 feet is recommended.
  • Don’t put flower beds right up against it and then introduce water right next to the foundation wall. Leave a minimum of 12” space between plants and the foundation wall.
  • Line your foundation wall with impervious material and maintain it regularly to make sure no cracks or areas of seepage develop. 12” of concrete or other impervious material is recommended.
  • Make certain that there are no cracks or defects in the foundation wall and keep an eye out for them. A tiny crack will grow much faster than you think.
  • Make sure that you have adequate water sealing on the walls of your home. New structures should have it on the outside as well as the inside.

Making certain that these steps are followed to waterproof your basement will rid you of a lot of headaches later on.

Dealing with mold and mildew

Keep in mind that where there is moisture, there is the potential for health issues due to mold and mildew. Even when you have properly waterproofed your basement, there is a tendency for basements to retain moisture from internal sources. Some of the main issues to guard against for internal moisture are:

  • Unvented driers.
  • Showers and other indoor plumbing fixtures.
  • Cooking
  • Humidifiers
  • Condensation from warmer, outside air.

Make sure that your fixtures and appliances are well vented and that your plumbing fixtures are well drained. Basements tend to be more humid than other parts of the house, so don’t add to that humidity by using a humidifier. Do not cool your basement using outside air.

Plumbing Challenges

Plumbing in basements create a whole new set of challenges, including the ones that we’ve already discussed. The major issue involved is the fact that water doesn’t run uphill. You have to get sewage from showers, toilets, sinks, washers and other fixtures up to the proper level so that it can drain into the sewer system outside your home. To do this, you’ll need to pump it up to the required level. Planning for and having a sump pump will be a necessary part of your home design. Additionally, plumbing from the rooms above will have to be dealt with in a space between the floor above and the ceiling of your basement. Understanding the challenges with plumbing shouldn’t cause you to avoid putting in a basement, but these challenges need to be addressed during home design so that surprises don’t pop up later.

Load Designs

When you place a whole under an area that is meant to be supported by earth, you have to plan how the structure above is going to be supported in that empty space. In many cases, there will be columns and beams that are necessary to support the floor and wall structure of the floors above. Make certain that you take these structural members into consideration when you are creating the floor plan design of your basement. In some cases, you might even make good use of those structures within your design to provide a special feature in your basement.

Professional Help

All of the issues raised above can also come with a set of local code requirements to complicate things further. It is best to seek professional help when designing a basement, in order to avoid and deal with the special set of challenges that arise out of including a basement in your building design.


Basements can serve a special purpose and be a functional living space that enhances the value of your home. Though there are waterproofing, mold and mildew, plumbing and structural problems, seeking help to make certain that those issues are dealt with during the design phase will help you to avoid surprise problems later on.

Share On Facebook
Share On Twitter
Share On Google Plus
Share On Linkedin
Share On Pinterest