There are many signs to look for your home may have an excessively leaky attic or basement. When your home is drafty, it could lead to an entire host of issues in addition to higher energy bills and an overworked furnace. Depending on the source of the draft, this could include anything from leaks to rot and black mold.
You will want to definitely consult a professional if;
-You have drafty rooms (may be more than old windows)
-Ineffective heating or cooling with constant furnace/AC running
-Dusty rooms (an indication of leaky ducts)
-Rotting wood and black mold, especially where lines and pipes may punch through an outside wall
-Excessive energy bills
The best way to address draft issues is having professional evaluate your individual situation. Drafty attics are common thanks to all the piping and wiring that punches through walls and insulation. Spray foam insulation is the best option in the market today, as oppose to traditional fiberglass insulation. The newer spray foam option is optimal for snuggly and effectively plugging leaks and protecting your home from the elements.