How to Finish a Basement

Basements flood for myriad reasons that must be resolved before the project can come to completion.

Flooding can occur because street sewers back up or because the grading around the home is inadequate to move water away from the foundation. There can be cracks in the home’s foundation wall that allow water building up outside the wall to penetrate. Each of these issues has a solution, and a talented general contractor familiar with flooding issues can help you resolve them and waterproof your basement.

In addition to being susceptible to flooding, basements can seep due to exposure to moisture. Concrete is a porous material and will allow water to seep through the walls. Basements with evidence of seepage need to be sealed properly. There are numerous sealing options, depending on why your walls are seeping and where it’s coming from. Make sure your contractor carefully inspects your basement for seepage as part of the planning process, and he or she can go over the options that work for your budget.

Now that you know you’ll be dry, it’s time for design plans.

Whether you are working with an architect, designer, contractor or tackling the project yourself, always make a plan for your basement first! You do not want to get into the construction without knowing what is coming next. “Winging it” will lead to issues down the line that you didn’t originally anticipate, and ultimately increase costs.

Think about what you need from the space functionally and don’t be afraid to explore numerous options. A great basement design to fit your needs may not be immediately apparent. It takes time and requires a lot of ideas to go through. If you’re working with a good professional, what might seem like wasted time is not wasted at all; it’s the process of creating, which by its nature should not be linear. Remember, design is often the least expensive, yet most important, part of your project. The key to success is finding a qualified professional you trust.

Now that your basement is dry, planned and the proper height, it’s time to build walls.

When your contractor goes over how to frame a basement wall, he or she will specify exactly where the walls should go, and a good contractor should get them in the right place. The contractor will measure your space and mark out where the walls go. In nearly every case, some minor adjustments will be necessary; a half-an-inch here and an inch there. This is fine so long as the critical distances are taken into account. A five-foot tub cannot go into a 4-foot 10-inch space easily, and a 3-foot refrigerator and 4-foot base cabinet cannot fit in 6-foot 11-inch space.

Beyond small adjustments, you probably know your basement layout better than the contractor or his carpenter, so it never hurts to walk around when they have the space marked out and again as the framing is done. A good contractor will appreciate your questions, as you may catch a mistake and save him a lot of work down the line.

One technical note: all wood on the bottom plate of the walls should be treated lumber in a basement.

Basements are inherently cool because warm air rises, meaning most of your home’s warm air will be heading toward the attic. In addition, the ground outside your basement walls will be cool to freezing depending on the climate and time of the year. It will never be warm. This means that good insulation in the walls and underneath the slab is essential to creating a cozy environment.

The walls can be insulated with 2×4 walls containing batt insulation, or foam boards can be glued to the outside walls and framed walls can be built inside. This provides a good thermal barrier, but does decrease the size of your basement because of the increased thickness of the wall.

If no foam insulation barrier was laid underneath your slab, you can still insulate your floor with a number of products. Some provide a surface for applying tile, others provide a subfloor suitable for hardwood application. The correct product depends on the intended use. Your contractor can guide you to the best options.

The walls are in the right place and the electric elements are in, so now it’s time for drywall. Before proceeding, walk through each room and make sure every electrical location, plumbing location, wire and vent are in the right place. Everything should be tacked down if it needs to have specific location – this is particularly important for wires. It also doesn’t hurt to photograph each wall so you know what is where before it’s covered for the future, in case you want to make a change. What could be an easy fix now becomes much more difficult after drywall is placed.

Drywall sheets are layed horizontally and pull through each electrical element. Those that are not tacked down will be pulled through randomly. The dry-wallers may encase some elements behind the drywall, so it’s good to take out your photos and carefully walk your place. Your contractor should do this, but if not, you’ll save yourself and your contractor a lot of grief.

If everything has been pulled though properly, three coats of mud is applied to the walls, sanding in between each coat. It’s good to cover the air intakes during this process if you have a forced-air system to keep the dust out of your furnace. A good plastic barrier between your living space and the basement is essential to keep dust from filling your living area. Still, expect some dust; it’s nearly unavoidable, though some contractors can put in dust collectors that collect or vent the dust to improve the situation.