Warehouse loading bays
Loading bay doors
The door at a loading bay opens and closes more times in a week than anything else in the building, and every one of those cycles is time the bay is not working and air the building is losing. Which door suits a bay is mostly a question of how often it moves, and only then of what it is made from.
Start with the cycle count, not the catalogue
A door that opens twenty times a day and a door that opens three hundred times a day are different products, even when the opening is the same size. The first can be chosen on insulation and price. The second is a moving machine under continuous duty, and the things that decide whether it was the right choice are its speed, the life of its drive and how it behaves when something hits it.
This is the reason a door bought on purchase price alone so often turns out to be the slowest part of a bay. Fifteen seconds to open, two hundred times a shift, is fifty minutes a day of a bay standing still, and it is a cost that never appears as a line anywhere.
Rejuva specifies the door against the duty the bay actually has, which means establishing the cycle count, the size of the opening, what the building holds behind it and how exposed the elevation is, before the door type is chosen at all.
The three doors a loading bay is usually choosing between
Most bays end up with one of these three, and the right one follows from the duty rather than from the budget.
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Industrial sectional doors
Sectional overhead doors are insulated panels that rise and run back along the ceiling, so nothing takes up space in front of or behind the opening. The best insulation of the three and the usual default for a bay that cycles moderately. Panels are replaceable individually after an impact, and high lift and vertical lift versions exist where the headroom allows.
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High speed doors
A flexible curtain that opens and closes in a fraction of the time, for bays cycling constantly or separating two conditioned areas. It buys back the time and the air a slower door loses, and it costs more to buy and has more to maintain. Most are designed to release and reset after an impact rather than break.
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Roller shutters
A curtain that coils above the opening, taking the least space and costing the least to buy, with the weakest insulation and the slowest operation. It remains the right answer for a secure external opening that is not cycled often and does not separate conditions.
A site with several bays does not have to choose once. It is common for the bays that turn constantly to take a high speed door and the rest to take sectionals, and that is usually the cheapest correct answer.
Where doors actually fail
Doors at loading bays do not usually wear out. They get hit. A forklift catching the bottom section, a trailer reversing into a partly open door, a mast raised too early: those are the events that take a door out of service, and they are frequent enough that how a door behaves when it is struck is a specification question rather than an accident.
It is worth knowing which failure mode you are buying. A sectional door that takes an impact loses a panel, which is replaced without changing the rest. A high speed door of the right type releases from its guides and is reset, sometimes without a call-out at all. A roller shutter struck hard is usually a whole curtain.
The other half of the answer is not the door. Impact posts and guides either side of the opening stop most of these events reaching the door in the first place, and Rejuva installs those under industrial protections, which is where dock face protection is published.
What else the door has to answer to
Three requirements that regularly change the specification after the type has been chosen.
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Fire compartmentation
Where the opening sits on a fire compartment line, the door is part of the compartmentation and its rating is not negotiable. This is established from the building rather than from the bay, and it is the requirement that most often rules a door type out.
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Wind loading on the elevation
An exposed elevation loads a large door hard, and a curtain rated for a sheltered opening will not sit still on it. It affects high speed doors most, since the curtain is flexible by design.
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Safety devices and their inspection
A powered door is machinery. Its safety edges, photocells and any anti-fall device are what stop it being dangerous, and they need periodic inspection along with the drive. A door on no schedule is a door that will fail while it is in use.
Frequently asked questions
Sectional or high speed, if we can only afford one upgrade?
Count the cycles. Below roughly a hundred openings a day the sectional is usually the better value and the insulation earns more than the speed would. Well above that, the high speed door pays for itself in bay time and in air not exchanged, and the calculation stops being close.
Can we keep the opening and change only the door?
Usually yes, and it is the least disruptive change to make at a bay, because it does not involve the pit or the slab. What needs checking is the headroom, the side room and the structure the tracks fix to, since a high speed door and a sectional want different things there.
Our door keeps being damaged. Is a tougher door the answer?
Partly, and usually not mainly. A door chosen to fail gracefully will cost you less over its life than one chosen to resist, but the larger saving is in stopping the impacts: protection either side of the opening, and a look at why the vehicle is where it is. That is worth establishing before spending on the door.
Do high speed doors work outside?
Yes, where they are specified for the exposure of that elevation. Wind is the constraint rather than weather, and an external high speed door on an exposed face is a different specification from an internal one between two areas. Tell us which face it is on and we will confirm it.
Do you maintain the doors you install?
Rejuva delivers the installation and sets up the inspection regime the door needs, which for a powered door covers the drive, the safety edges and the photocells. A door at a bay is under harder duty than almost any other door in the building, so it belongs on a schedule from the day it goes in.
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.