Dock shelters seal the space between the building and the vehicle, adhering to these with two lateral and one superior armoured rubber leaves (in some case made of PVC) kept at flag position by the structure of the dock shelter which is protruding from the wall, and is covered at the sides by a generally clear fabric (yellow or light grey) through which the daylight filters and which avoids the necessity to turn on the lights.

A very important characteristic is its capacity to unload the water, which always forms on the roof, also if the roof is in slope, and that arrives at bucketful on the operators during the drive back of the vehicle. The models foreseen with drainage system are to be preferred, for example gutter-pipe bringing water to ground level, gathering it through holes on the roof.

The lip of the dock leveller seals against the vehicle. Laterally down there remain two small-uncovered areas where it might be possible to apply some optional seal triangles, that usually are a dangerous place of dirt and cigarettes buds, besides being inefficient, because they never are able to well seal.

The dock shelters must resist the possible wrong manoeuvres of the docking vehicles; they must retract under the shock and extend when the lorry drives away. Because of the retractable structure, the pressures transmitted by the vehicle are not dangerous. It is to be taken into consideration the possible side displacement of the queue of the very long vehicles, and make sure that their docking and their departing are straight for at least one and a half meters from the dock.

The dock shelters are fixed on the wall (that must be straight and on the same level) with expansion bolts, and the wall must be sufficiently consistent to keep them. In opposite case, for example the sandwich insulated walls with rock wool inside, the constructor must foresee anchoring points.

Strong windy conditions, especially wind gusts, may damage the dock shelters curtains that stay at flag. In spite of the strong double inside armouring, the shacking caused by the wind gusts in some particularly windy places (for example on the coasts) may cause the curtains to cut. In these zones it is necessary to install dock shelters specially reinforced against these accidents; generally it is sufficient that part of the curtains blocked as sandwich into the metallic structure is reinforced with an additional portion of curtain on each side.

Dimensions of Dock Shelters: the Width

Note: the step of the loading bays, in this publication, always counts the minimum physical possibility in regards to the vehicles, and it is not a constant operative suggestion. The step of the bays must be reported also to the logistic internal use, and the consequence is short step for the couriers, and longer steps for the industries.

Dock Shelters for Vehicles with Rear Doors

They must be chosen in function of the maximum dimensions of the vehicles that will load: if they are vehicles with rear doors, the standard universal type for bays step 3.5 metres has to be chosen.

In this case the dock shelter is 345 cm wide and 345 cm tall and it is to be installed starting from above, at 450 cm from ground. In this way it takes vehicles with maximum height from ground from 3.5 m to 4.2 m (some vehicles may be also out from the maximum height).

Dimensions of Dock Shelters: the Depth

The standard depth of dock shelters must be of at least 70 cm. In opposite case the vehicle driving back will "pinch" the side curtains between the body and the bumpers, or between body and the lip of the dock leveller, causing damages and leaving partially covered the rear opening of the vehicle by the curtain. In some cases dock levellers are designed protruding from the dock rim, e.g., by 40 cm, and in this case it is necessary to foresee dock shelters 100 cm deep, in order to avoid its immediate breakdown.

Dimensions of Dock Shelters: the Height

The dimension in height of the dock level dock shelters is standard 345 cm. This dimension comes from the top of the installation, going down from 450 cm from ground; the dock shelter ends consequently at 105 cm from ground and includes all the vehicles. In case the docking of lowered truck-bed vehicles is the ground, dock shelter can be chosen.

Retractable Dock Shelters: Ground Level

The ground level dock shelters have a standard height of 445 cm and are used for the vehicle openings of the building without dock, or in cases of constant docking of "lowered truck-bed vehicles" They have two standard dimensions, the first one for doors with maximum width of 320 cm, and the second for passing doors of 4 m of width:

• 345 cm of width, 345 cm of height and 70 cm of depth, with side curtains of 70 cm, they have to be installed on doors with a maximum of 320 cm of opening width
• 420 cm of width, 450 cm of height, 110 of depth with side curtains of 110 cm, for vehicle doors with opening until 4 m of width and 4.4 m of height

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