How to Remodel a Basement and Prevent Future Mold Growth
When you need more space at home and have an unfinished basement, the obvious solution is to finish the basement; however, many homeowners complete this costly project only to have mold and mildew grow over time. Follow these instructions to remodel your basement while protecting it from mold.
Step 1 - Inspect Foundation
Look for cracks and leaks. If you discover either of them, you must make repairs before continuing. Click this link for instructions on repairing cracked foundations.
Step 2 - Clean and Waterproof Foundation Walls
Several products, including Hydraloc and DryLock, offer an effective solution for do-it-yourselfers. Consult the manufacture's instructions before applying either of them.
Step 3 - Lay Out Perimeter Walls
Check the concrete walls to determine whether they are level. If they are within .5-inches, measure 4-inches off each corner at the floor and make a mark. Doing so will allow for a .5-inch space between the wood and concrete.
Snap chalk lines on each mark of your 4 corners to establish the location for your bottom plate. Level-up from your chalkline and mark the ceiling joists in each corner. Snap lines along the ceiling joists for your top plates.
Step 4 - Frame Perimeter Walls
Install your top and bottom 2x4-inch plates on your chalk line. Install bottom pressure treated plates using the Hilti gun. Install top plates using the framing gun. Be careful not to nail through wires or pipes. After both the top and bottom plates are installed, measure every 16-inches and install a wall stud. Height measurements may vary.
Step 5 - Lay Out/Frame Interior Petitions
Using the same method in laying out the perimeter walls, snap equidistant lines on the floor for each room. Level-up and snap the same lines on the ceiling joists. Install top and bottom plates. Fill in each stud every 16-inches and frame all door openings 2.5-inches larger than the door. For example, a 3-foot door needs to be framed at 38.5-inches.
Step 6 - Insulate
Install rigid .75-inch insulation along the perimeter walls. Rip the insulation at 14.5-inches and press it firmly into each stud bay. Ensure that the insulation does not touch the concrete walls. Do not insulate the ceiling. Open ceiling bays allow for proper air flow between floors.
Step 7 - Install Sheetrock
Begin with the ceiling. Install sheetrock using 1.5-inch sheetrock screws, 7 at each seam and 5 along each joist. All screws should slightly break the sheetrock casing. Stagger your seams. install Sheetrock on the walls beginning at the top. Leave a 3/8-inch gap at the bottom of the concrete floor.
Step 8 - Flooring
Do not use cross hardwood flooring. It is too expensive and is not conducive to a basement environment. Determine whether your concrete floor has been installed with a vapor barrier. To do so, tape a piece of 12x12-inch plastic to the floor. Leave it there for 24 hours. If there is moisture on the plastic, assume that there is no moisture barrier under the concrete.
Install a .75-inch cellulose underlay before installing carpet. The best option is a composite wood flooring. Some composite flooring offers this cellulose barrier attached to the floating flooring itself.