No matter how high tech our ovens, ranges and other appliances get, we’re sometimes still driven to try old fashioned fixes. I’m sure that you hate when your food overflows and spills on the bottom of the oven. You know its just gonna burn off and smoke up the joint before its gone. So you quickly try mom’s old trick of lining the bottom of the oven with foil. Maybe not such a great idea with today’s high powered, but delicately balanced ovens. I found this piece in a Missouri paper called the News Leader.

You want to keep your oven sparkling clean so you protect it by putting aluminum foil on racks, under food as it cooks, and down on the oven floor where food drops and burns to a crisp. But instead of helping, you’re hurting your oven.
Foil placed on the oven floor reflects and intensifies heat, which can cause the bake element to burn out prematurely.

Foil placed under foods on the racks is bad because it traps heat in the bottom of the oven, keeping it from circulating and reaching the heat sensor near the top. Severe overheating is possible; besides damaging the bake element, that could also affect insulation in the oven wall and discolor or even crack oven-door glass.

By disrupting temperatures and air circulation, aluminum foil messes up cooking times, too.

A quickie clean just isn’t worth it.