What may happen to ducts if not properly insulated in a crawlspace?

Ducts that are not properly insulated in a crawlspace can indeed lead to significant energy loss, particularly in terms of heating and cooling efficiency. When ducts are exposed to the unconditioned air of a crawlspace—especially if that space experiences extreme temperatures—the temperature of the air within the ducts can change.

As the warm air from heating systems travels through uninsulated ducts in cold environments, it cools down, causing the system to work harder to maintain the desired temperature inside the home. Conversely, air conditioning systems can face similar issues, as cooler air can warm up when passing through ducts exposed to heat. This inefficiency not only increases energy costs but can also lead to uneven temperatures within the home, negatively affecting comfort and potentially shortening the lifespan of HVAC equipment due to increased strain.

Proper insulation of ducts helps to maintain the temperature of the air as it travels through the system, ensuring the efficiency of both heating and cooling systems.