Published on January 4th, 2014 | by Henri


Heating and ventilating a finished basement

Q.    We have done some renovation in our basement. We have installed a washroom, created two work stations, and left an open space for other recreational purposes. We have also enclosed an area that has the water tank (we have well water and septic system) that is used for the storage of pots, pans and other miscellaneous items. We are faced with two major concerns and seek your advice on the following:

  1. How do we provide ventilation as well as heat to the basement area? (No vents were installed at construction.)
  2. The walls of the storage area that was Sheetrocked and painted has begun to mildew and it is spreading over most of the base of the walls. What corrective action is recommended to cure this problem?

We should add that although this storage area had no vents, prior to the installation of Sheetrock and painting, there was no seeping or visible water marks on the walls in the area.

If you could provide your expert advice on how we could handle the concerns mentioned we would be very appreciative.

A.    You do not need ventilation in a basement; opening windows in summer would create a bad moisture problem.

Heat should be provided with an extension of your present heating system. If you have a hydronic (hot water) system, a separate zone for the basement is the best solution. If you have a warm-air system, heat ducts should be installed properly (not simply cut out of a main in the basement). Ducts should be run down to the floor with multi-directional grilles. An experienced HVAC contractor will know how to do this.

Mildew that has developed at the base of the walls tells you that you have a very high relative humidity and you need to operate a dehumidifier in the warm months of the year. Select one with a large enough capacity to handle the cubic footage of the basement and keep all doors to the various spaces open, but if this is not possible and you need to keep doors closed to some of the spaces, you may need more than one dehumidifier.

Facebookredditlinkedinmailby feather

Tags: , , , , , ,

About the Author

Back to Top ↑