Sectional Door Installation, Site Preparation and Sequence
Published:
Publisher: Alkur Kapı Sistemleri A.Ş.
Summary
The sequence for installing a sectional door is the same regardless of lift type: sub-frame check, counting the parts, tracks and curve profiles, squareness confirmation, track assembly, panel stacking, spring assembly and commissioning. Squareness is not a single step but a check repeated at every stage. Spring and cable work belongs to a trained team.
Most of the hours lost on installation day come not from the installation but from work that was not finished before it: the sub-frame left out of square, the floor level off, no electrical supply run, or parts missing from the delivery. This article covers both what has to be ready on site and the sequence itself, following the flow in our own installation manual.
The reader in mind is the installation team and the contractor preparing the site. Measurement and lift type decisions belong before this stage; we have separate articles on both.
What has to be ready before installation?
The opening must be clear — formwork, temporary frames or coverings removed, lintel and jamb walls at their final level.
The sub-frame must be built and square — diagonals equal. Where there is no frame, it is built before installation.
The floor must be flat and at one level, particularly across the area where traffic and loading will take place.
The electrical supply must be run — at the voltage the door type requires, with the fuse capacity in the panel, and close to the mounting point.
The working area must be cleared — the volume the leaf and tracks are fitted in, plus clean ground for laying out the parts.
In cold stores and in food or pharmaceutical environments, hygiene and temperature conditions have to be maintained throughout the installation, and that shapes the plan as well.
Equipment: what to bring to site
The tool set for sub-frame and door installation is: welding machine, rotary hammer, angle grinder, drill and screwdriver, extension lead, 10 socket head, spanner set (10-11, 12-13, 14-15, 16-17), ratchet handle, two spring winding bars, adjustable pliers, hammer, flat and cross screwdrivers, hex key set, tape measure, level, plumb line, multimeter, voltage tester and ladder.
Two items get overlooked and bring work to a halt: there must be two winding bars, and a multimeter for the electrical checks.
The sequence
The order is the same for every lift type; standard, high, vertical and following high lift all take the same path.
1. Sub-frame check. Dimensions and squareness are verified. On an out-of-square frame the tracks will not sit parallel, and this cannot be compensated during installation — it is corrected at the frame stage.
2. Parts check. All parts are unpacked onto clean, level ground, counted individually and inspected for damage. A missing part should surface at the start, not halfway through.
3. Tracks and curve profiles. The left and right tracks and the curve profiles go up. Before this step the floor must actually be checked for level; an installation begun on the assumption that it is flat cannot be completed properly.
4. Squareness and parallelism. The diagonals of the fitted tracks and curve profiles are measured to confirm square, and parallelism is set. For the door to run properly, this check is repeated at every stage.
5. Track assembly. Tracks and L profiles go up with their brackets and hanging brackets. The arrangement changes with lift type; in low headroom applications, single and double track use different top hinges.
6. Panel stacking. Start from the bottom panel and work up. As each panel seats, the centre and side hinges are connected and the roller holders fitted. The step repeats to the top panel, checking alignment on each.
7. Spring assembly and cable. With stacking complete, work moves to the mechanism. Depending on door size and lift type, the door may be single-spring or run three or four springs, and the shaft may be one piece or coupled. The cable is wound 2.5 turns onto the drum; on high lift, a distance equal to the high lift dimension is left empty below the relevant section.
8. Balance and commissioning. The door is balanced, the limits taught and the safety equipment tested.
Spring and cable work is not done by estimate
Spring calculation, winding and cable work carry a serious risk of injury and must be carried out only by a trained installation team, following the procedure in that model’s manual. Settings are not guessed at on site; the values in the specification are used.
The automation side
The motor and control unit go on once the door mechanics are complete. On industrial doors the drive is usually shaft driven, with a chain mechanism for moving the door by hand during a power cut. Keeping that chain reachable has to be planned during installation; a chain that ends up behind racking, pallets or machinery is of no use in an outage.
On the control side, supply type governs: with three-phase direct drive the I-380 board monitors phase sequence and phase loss, while driving a three-phase motor from a single-phase supply makes the FU inverter mandatory. The control board should be settled together with the motor; changing it later means redoing the cabling and the limit learning.
What commissioning tests
Commissioning is more than checking that the door opens. In order: leaf balance (released by hand, it should stay at any position), limit positions, the photocell beam line and how the door responds when it is broken, edge protection, emergency stop, that the manual release works, and finally the remote and activation devices.
The result should be recorded and handed over to the user. Re-checking leaf alignment, cable tension and the safety equipment within the first week catches the small deviations that come from settling.
Three recurring site mistakes
Reducing the squareness check to one occasion. The check at the frame is assumed sufficient; alignment may have drifted by the time the track assembly is up.
Judging the floor by eye. A level difference is usually invisible and has to be measured; the bottom seal then fails to close fully.
Leaving the electrics to installation day. Without a supply the mechanical work finishes but commissioning cannot, and the team returns to site a second time.
Our installation manual, size confirmation forms and operating instructions are on the Catalogues and Documents page, and the same files appear in the documents section of the relevant product pages.
