Allowable Deflection for Modular-Freezer Ceiling Panels

Deflection

• Deflection refers to how flexible the freezer panels are, a measurement of how much panels bend under common stresses. Flexibility may seem like a good quality, but the freezer panels need to be strong enough to hold a large amount of weight, not to mention deal with extreme temperatures. A large amount of deflection means that a panel is not properly supporting surrounding weight and is not durable enough for the job. So, regulations specify maximum deflection limits of freezer panels.

Insulated Panels

• For general insulated panels, the maximum deflection rating is usually L/180. This is a basic deflection equation, where deflection equals the length or span of the panel, divided by 180. The result is expressed in inches, meaning that a certain number of inches in deflection is allowed, but no more. A panel 6 feet in length, then, would have a maximum allowable deflection of 0.033 inches.

Roofing

• Roofing or ceiling panels may have different deflection ratings than the average panels used in the building project. This depends on the freezer and the local guidelines, but ceiling panels may be under more stress than other panels in the freezer and require stricter parameters to ensure freezer safety. For this reason, the allowable deflection is often L/240. Other, more specific, requirements may be in place depending on area, but the L/240 guideline is useful as a general examination of materials.

Live Loads and Dead Loads

• Deflection ratings are calculated with live loads and dead loads. A dead load is the normal weight that the panel must bear at all times. In this case, the deflection requirements are much lower -- only a small amount of deflection is allowed. Live loads refer to weight that can be taken on and off the panel, depending on how the freezer is used, and these loads allow for greater deflection. If your panels come with separate live and dead load calculations, use the proper version, depending on how your freezer is set up.