Adding a foot of additional depth to a basement by lowering the floor is possible. The risk of success is the existing depth of the sewer pipes beneath the basement floor. If the sewer pipes under the basement concrete floor are buried deep enough below the floor to allow this floor “lowering” to work (12”-18” below the floor), then it can be affordable. If the sewer pipes are not deep enough or the sewer pipe entrance into the house itself is not buried deep enough then this process gets very labor intensive and costly.
Height can also be gained by adding a foot to the top of the basement walls. The scope of work would include: disconnecting all utilities, moving or raising the house from its foundation, demolishing the old concrete foundation and building a new taller foundation (which includes replacing all the utility services mentioned above), reinstalling the house onto the new foundation and reconnecting all utilities.
Just the description of work reveals the substantial budget. The general budget range is about $50-$100k to “move a house” correctly. The foundation replacement part is the easiest section of the work, with the cost being driven by all the labor intensive utility stuff and peripheral work.
As you can see the practical answer is generally no. Most of the houses we check for this possibility are 90% “No” because, typically, the sewer pipes are buried just below the concrete basement floor. When the house is first built there is no apparent reason to bury the sewer pipes any deeper than necessary. So I am skeptical that this project can be cost effective.
For remodeling and repair services in Metro St. Louis, call Mosby Building Arts at 314.909.1800 or contact them here.