Dock seals and dock shelters are two completely differently designed products with one primary goal in mind, conserving energy at an open loading dock overhead door.
The overhead door height and width determines the most practical choice between a dock seal and a dock shelter.
A dock shelter can be used on any size of standard overhead door however a compression style dock seal provides the most effective energy saving solution on overhead doors that are up to 9’ wide x 10’ high.
Conventional dock seals consist of 3 pieces; 2 foam side pads and either a head pad or a drop curtain and acts as a compression seal at the loading dock overhead door.
Specified correctly the dock seal should project a maximum of 4” – 6” beyond the face of the dock bumpers. With a truck backed into position up against the dock bumpers this 4” – 6” of compression forms a gasket seal on the sides and the top of the back of the truck.
In addition to conserving energy at the open overhead door this gasket seal also effectively keeps rain from entering the loading dock bay. Keeping rain away from the loading dock bay maintains safe traction for the lift truck and loading dock attendants as well as minimizes any potential water induced product damage during loading/offloading.
A dock shelter is a 3 side rigid frame assembly that commonly projects 24” beyond the exterior building wall. This 3 piece rigid frame assembly consists of 2 side frames and a head frame. The side frames have 2 perpendicular side curtains c/w fiberglass stays/stiffeners and the head frame has a drop curtain c/w fiberglass stays/stiffeners.
With the dock shelter in place the truck backs through these 3 projected curtains and the curtains create a brush seal along the sides and top of the truck minimizing energy loss when the overhead door is open. This design of dock shelter provides unlimited access to the back of the truck with the trucks door(s) open because the seal effect is on the sides and top of the truck as opposed to the back of the truck.
There are many product enhancements for standard dock seals and dock shelters designed to both extend the life of the dock seal and dock shelter and to also improve the energy efficiency at the loading dock.
For example dock seal side pads are available with optional wear pleats, these sewn on the top only wear pleats are a shingle design. During regular loading off-loading it is common for the truck bed to move up and down causing an abrasive effect on the face of the dock seal side pads. Dock seals with wear pleats on the face of the side pads minimize the abrasive motion as the wear pleats move up and down with the truck bed.
Dock shelters are available with inflatable side bags and an inflatable head curtain that when activated inflate and contour tightly to the sides, corners and top of the truck further improving on energy savings.