Avoiding Finished Basement Water Problems

Before I undertake a project to finish a basement, I gauge the potential threat of water and moisture.  A significant water problem may mean making major changes to the plan or even abandoning the project all together.  If the homeowner has lived in the house for many years and claims that water has never appeared, I breathe a little easier.  But, it’s always wise to actively look for trouble early on and take appropriate steps to prevent issues later.

Close inspection of the basement floor can reveal traces of previous water damage. In addition, I sometimes soak the outside foundation perimeter using a garden hose and then check the basement interior for seepage. But the best determinant is a sump pump pit installed in the basement to monitor ground water levels. (At some point, installing the sump pump itself is always a good idea to accommodate extraordinary deluges even if normal water levels are not a concern.) Here in the Canton, MA basement that is the focus of this blog post, the sump pump pit revealed no ground water. Nevertheless, when we get to this step, we will use FreeFit 100% waterproof, fully floating vinyl tile flooring with a 15 year commercial warranty. There will be more on flooring later near the end of the project.

Visible or not, moisture seepage and/or condensation afflict the walls of basements and should be addressed with a thermal break and vapor barrier if the basement is to be finished.  Under-managed moisture is not only a threat to building durability, but it also can lead to mold and mildew which can be a serious health concern for a homeowner and family.  Some builders recommend rigid foam board insulation between the concrete walls and sheetrock, but I prefer a sprayed in closed cell foam insulation like the Icynene product.  Not only is it quicker to install than the foam boards, but closed cell foam insulation expands to fill gaps and cracks, delivers a higher R-value per inch (insulation effectiveness), and provides additional structural strength to a wall or ceiling.  Additionally, it provides a continuous vapor barrier; no need to fill and tape any seams as required with foam board. 

Having assured myself that the ground water level and wall moisture in my current basement job are manageable, I am proceeding with the renovation.  As with most construction tasks, careful site analysis and preparation (in this case, to guard against water in a basement) are key to the long term success of the job.

Craig Carter