Warehouse loading bays
Dock shelters
When a trailer is docked, the gap around it is an open doorway the width of a lorry, and it stays open for as long as the load takes. A dock shelter closes that gap, sealing against the back of the vehicle so that the air inside the building, the condition of the goods and the weather outside stop being the same question.
What is actually leaking
A bay without a shelter is not sealed by the trailer parked in it. There is a gap above the vehicle and a gap down each side, and the shape of it changes with every different trailer, which is why it is rarely noticed as a hole: it never looks like one.
What comes through it is heat in winter and heat in summer, rain onto the dock apron and onto whatever is standing on it, and the birds, dust and leaves that a yard produces. On a chilled or temperature controlled site it is also the condition of the product, since the cold air is going out at the same rate the warm air is coming in, and the plant is working against it the whole time the bay is open.
Shelter or seal, which are two different products
The words get used interchangeably and they are not the same thing. Which one suits a bay depends on how consistent the vehicles are.
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Curtain shelter
A frame carrying flexible curtains that the trailer reverses into, which then close along the sides and the top. It tolerates a wide range of vehicle sizes and shapes, which makes it the usual answer for a mixed fleet, and it makes no contact hard enough to mark a vehicle.
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Inflatable shelter
The seal inflates around the vehicle once it is in position, so it adapts to the trailer rather than the trailer having to fit it. The tightest seal of the three and the choice where the condition inside is what the site is judged on, at a higher price and with a powered component to maintain.
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Foam dock seal
Compressible foam pads mounted around the opening, which the trailer presses into as it docks. Simple, robust and the cheapest to own, with the tightest tolerance: it seals well against the vehicle it was sized for and less well against anything much different.
The spread of trailer heights and widths a site receives is what decides between them, which is why it is the first thing the survey establishes.
The argument on an ambient site, and on a chilled one
On an ambient warehouse the case for a shelter is the heating you are not putting into the yard, the water that is not reaching the dock apron and the goods standing on it, and the housekeeping that a sealed bay stops generating. It is a running cost argument, and it scales with how many hours a day your bays are occupied rather than with how many vehicles you turn.
On a chilled, frozen or temperature controlled site the argument changes shape entirely, because the seal is part of how the site holds its condition. Every minute a bay is open with a poor seal is refrigeration plant working against an open door, and it is also a temperature record somebody has to explain. That is why the specification is stricter there and why the inflatable variant is more common on those sites.
Rejuva does not publish a saving figure for either case. What a given bay saves depends on the climate, the hours the bay is occupied, what the building is heated or cooled to and what the seal replaces, and that is what the survey is for rather than a percentage from a brochure.
What the survey has to establish first
A shelter that does not fit the vehicles is a shelter that seals some of the time, which is the same as a shelter that does not work.
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The range of trailer heights
The tallest and the shortest vehicle that will dock, not the average. The spread between them is what rules the foam seal in or out, and it is the single number that most often changes the answer.
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How the vehicles approach
A driver reversing at an angle, or into a bay with limited apron, loads the shelter differently from one coming in square. It decides how robust the frame has to be and where the wear will happen.
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What the building is holding
Ambient, chilled or frozen, and whether the area behind the bay is conditioned at all. This is what sets how tight the seal has to be and therefore what it is reasonable to spend on it.
Frequently asked questions
What is the difference between a dock shelter and a dock seal?
A shelter is a frame with curtains that the vehicle reverses into, which closes around it. A seal is compressible foam mounted around the opening that the vehicle presses against. The shelter tolerates a wider range of vehicles; the seal is tighter and simpler but is sized for a narrower range. Sites with a mixed fleet almost always want the shelter.
Will an inflatable shelter be worth the extra?
On a temperature controlled site, usually, because it seals against the vehicle rather than requiring the vehicle to fit it, and holding condition is what that site is judged on. On an ambient site the curtain shelter is normally the better value, and the money is better spent on the door.
Can a shelter damage our vehicles or our customers' vehicles?
A correctly specified one should not, and that is part of what the specification is for. Curtain shelters are designed to give rather than resist, and where the concern is a haulier's trailers rather than your own, that is worth raising at the survey so the frame and the approach are chosen accordingly.
Can a shelter be fitted to a bay that already exists?
Usually yes. It mounts to the building around the opening, so it is the least disruptive of the four bay components to add or replace, and it does not involve the pit. What needs checking is the structure it fixes to and the clearance around the door.
How long does a shelter last?
Long enough that replacement is planned rather than sudden, and the wear is visible before it is a problem: curtains fray at the contact edges and foam loses its compression. Both are replaceable on their own without changing the frame, which is what keeps the whole life cost down.
The four parts of a loading bay
These are chosen together rather than one at a time, because each one constrains the next: the leveller sets what the bay can serve, the shelter has to seal around the vehicle it was sized for, and the door has to live with the pit underneath it.
Have a project in mind?
Describe what needs to happen in the building and we will come back with a proposed approach, the specialist who would carry it out and a budget you can work with.