Sectional Door Installation, Site Preparation and Sequence

An out-of-square sub-frame, unfinished floor, missing power supply or missing part can stop installation. This guide combines preparation checks for the site contractor and dealer installation team with the operation sequence in the NORMTOR 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.

Record the preparation checks

Check	Result to record	Next action if incomplete
Frame size and squareness	Measurements and deviation against the form	Project team corrects the supporting structure.
Floor level	Finished level and observed difference	Confirm the reference before finalising position.
Materials and damage	Identity of missing/damaged parts	Resolve the shortage before the affected operation.
Electrical preparation	Supply confirmed for motor/controller	Authorised electrical team completes preparation.
Track path	Obstruction and available working space	Resolve conflicts before progressing with tracks.

This record belongs to the installing dealer’s technical team. Alkur does not provide site surveys or on-site installation.

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 installation-guide drawings mark 2.5 cable turns for the drum and lift arrangements shown; a trained crew must verify winding and high-lift layout against the drawing for the specific door.

8. Balance and commissioning. The door is balanced, the limits taught and the safety equipment tested.

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.

Choose the controller, motor and site supply together. The published I-380 and FU documents describe different electrical applications; do not assume FU is mandatory for every single-phase-supply/three-phase-motor pairing or compatible with every sectional-door drive. Qualified installers must follow the current instructions for the selected motor and controller when wiring and setting limits.

What commissioning tests

Commissioning is more than checking that the door opens. In order: leaf balance (using the balance check defined in the selected door’s manual), 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.

Record the commissioning result and hand it to the user. Set subsequent inspection and maintenance intervals from the current manuals for the selected door, springs and motor and the facility’s usage; there is no universal first-week adjustment for every installation.

Three recurring site mistakes

1. 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.

2. Judging the floor by eye. A level difference is usually invisible and has to be measured; the bottom seal then fails to close fully.

3. 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.

What record should be complete at handover?

The installer records frame/track checks, the motor/controller and limit type, manual revision and actual commissioning results. An open finding needs its resolution and retest result recorded separately; “the door worked” is insufficient.

Explain use and manual operation for the installed equipment, and record the documents delivered and the instructions used to plan maintenance. This record does not replace a declaration of conformity. Product questions requiring manufacturer assessment are submitted through the dealer, distributor or partner.