Commercial overhead doors for new construction: what the building has to be ready for
A commercial overhead door on a new building succeeds or fails on four things that are decided long before the door arrives: jambs built for the door’s loads, reinforcing steel kept out of the fastener zone, a dedicated power supply sized for the operator, and a clear wall around the opening. The door industry publishes the numbers for each, and this page puts them in one place with the source beside every figure, for the people who frame, pour, wire and schedule the opening.
By Commercial Garage Doorman, Grimsby, Ontario · Updated
Pricing doors into a new building? Send the door schedule or drawings and the date the openings will be framed, and we quote from the drawings.
Request a new-build quoteWhat does a rolling door put on the building?
Two kinds of load. The dead load is the cantilevered weight of the curtain, counterbalance, hood, operator and brackets, carried by the wall above the opening. The wind load acts on the curtain and is passed through the guides into the jambs, both pushing into the building and pulling out of it. When a door has windlocks, a third force appears: as the curtain deflects and the windlocks engage, catenary tension pulls the guides toward the centre of the opening, parallel to the wall. Its size depends mostly on the opening width and the specified wind load.
Source: DASMA Technical Data Sheet #251, Architects and Designers Should Understand Loads Applied by Rolling Doors (PDF). Checked 23 October 2026.The practical trigger for the third force is width. DASMA’s sheet on door-to-framing interface tells designers that if a rolling steel door is greater than 8 feet wide, chances are it includes windlocks, and that the applied force values should be obtained from the door manufacturer. It also notes that those catenary figures assume the vertical jambs are rigid, and that if the specified door type changes during design, or a windlocked rolling door goes into an opening that held a different type of door, the jamb framing should be analysed again.
Source: DASMA Technical Data Sheet #292, Vehicular Access Door Interface with Building Framing (PDF). Checked 23 October 2026.Which wall conditions cannot carry a rolling door without more work?
DASMA names four site conditions that often cannot take a rolling door’s loads and may need evaluation with the door manufacturer. Each one is cheaper to settle on the drawings than on the day the installer arrives.
| Condition | The risk | What it needs |
|---|---|---|
| Windlocked door on light-gauge cold-formed steel jambs, high wind load | Jambs can rotate under wind and let the curtain blow out of the guides | Application-specific advice from the door manufacturer |
| Wall above the opening not designed for the door’s dead load | A face-mounted door can extend 12 to 36 inches or more above the opening, and the hood must fasten to it | Header wall designed to carry the cantilevered weight |
| Concrete block (CMU) jambs | Insufficient concrete strength for the anchors | At least a 2,500 psi rating on a reinforced CMU jamb; through-bolts in hollow block; anchors placed clear of rebar |
| Tilt-up concrete panels with steel jambs | Jambs flex or loosen under door loads | Steel jambs rigid and fastened the full height of the opening |
Where should the rebar go in a concrete or masonry jamb?
Out of the fastener zone. Door jamb fasteners are designed for specific locations, and moving them can reduce the door’s structural performance or void a fire rating, while cutting the wall’s reinforcement can reduce the building’s. DASMA’s typical jamb detail shows a reinforcement-free zone for that reason: vertical reinforcement within 2 inches of either corner of the wall at the jamb, and at least 6 inches from the edge of the opening. Where the rolling door drawings are not available yet, it recommends keeping vertical reinforcement at least 8 inches from the edge of the opening, if the wall’s overall structural integrity allows. Horizontal reinforcement shown on the structural drawings is still installed as shown unless the registered design professional changes it.
| Item | Recommendation |
|---|---|
| Vertical rebar, distance from the wall corner at the jamb | 2 inches maximum |
| Vertical rebar, distance from the edge of the opening | 6 inches minimum |
| Same, when the door drawings are not yet available | 8 inches minimum, if the wall design allows |
| Masonry cores at the jamb | Filled, as drawn in the typical detail |
| Rebar found in the way on an existing wall | Alternate mounting or door size first; otherwise a structural engineer decides |
Which wind load does the door have to meet in Ontario?
The one your local building authority sets. DASMA publishes a garage and commercial door wind load guide based on the 2010 National Building Code of Canada for code officials, engineers, architects and builders, and it says plainly that in all cases the local building authority is the sole and final determiner of the structural and safety requirements and the door’s suitability. Where testing is required, the guide points to ANSI/DASMA 108, with doors tested to both positive and negative pressure, and a manufacturer’s label certifying the load. On a project, that means the wind load belongs in the door spec as a number in pounds per square foot, positive and negative, before a door is ordered, and the door’s label should match it.
Source: DASMA Technical Data Sheet #155u, Garage Door and Commercial Door Wind Load Guide Based on the 2010 National Building Code of Canada (PDF). Checked 23 October 2026.What power does a high performance door need?
More than the drawings usually give it. A high performance door’s operator moves the whole door at speed, so voltage matters. DASMA strongly recommends a dedicated line for each high performance door, and warns that a supply shared with other doors or equipment can drop the voltage at the door below what the motor needs. On a 208 V three-phase supply feeding a 230 V motor, anything under 207 V measured during operation is liable to cause problems, and an electrician should be consulted if the three phases are not within 6 volts of each other. Site voltage is measured at the door controller. Where 480 V or 600 V is available, DASMA says it is better for these doors and should be used if possible.
| Point | DASMA’s guidance |
|---|---|
| Circuit | A dedicated line for each high performance door |
| Lowest operating voltage, 208 V supply | 207 V, measured while the door runs |
| Phase balance | All three phases within 6 V of each other |
| Where to measure | At the door controller, dormant, starting and running |
| Re-used wiring from an old door | May not carry the new door’s current; check the gauge |
| Preferred supply where available | 480 V or 600 V |
The same sheet says these systems should be installed by a trained door systems installer working with a licensed electrician. In practice that means the electrical drawings carry a dedicated circuit to each powered opening, and the supply voltage is confirmed before the operator is ordered, because the manufacturer matches the motor and controller to it.
Where does the door go in the spec book?
Division 08. In CSI MasterFormat, overhead coiling doors sit under 08 33 23 and overhead rapid coiling doors (high-speed) under 08 33 23.13. Getting the section right is what puts the door in the right subcontractor’s scope instead of between two of them.
| Door | Section |
|---|---|
| Coiling doors and grilles (the group) | 08 33 00 |
| Overhead coiling doors, including high performance | 08 33 23 |
| Overhead rapid coiling doors (high-speed) | 08 33 23.13 |
| Overhead coiling grilles | 08 33 26 |
| Overhead coiling fire curtains | 08 33 44 |
| Panel folding doors | 08 35 13.33 |
What goes inside that section, line by line with the test standard behind each, is in our guide to writing a commercial door specification.
What has to be ready before the installer starts?
The opening. DASMA’s note on common installation problems puts it in one line that every schedule should respect: commencing installation signifies installer approval of the wall conditions, so anything unsatisfactory is settled between the owner or general contractor and the installer before work starts. These are the conditions it lists, and the ones worth walking before the installer is booked.
| Check | What right looks like |
|---|---|
| Opening size | The door ordered is the door for this opening, verified before work starts |
| Jambs plumb | No waffled block, out-of-plumb pour or skewed steel channel |
| Opening square | Corners at 90 degrees, diagonals equal (3-4-5 or 6-8-10 check) |
| Jamb height | Jambs reach the top of the door, or spacers are planned for a smooth mounting surface |
| Floor and lintel | Known out-of-level is flagged; the barrel is installed level regardless |
| Fire door jambs | Gaps that would need a sealant bead wider than about half an inch are repaired first |
The wall around the opening matters as much as the opening itself. Conduit, sprinkler heads, unit heaters and light fixtures mounted where the coil, hood and operator have to go are the most common reason a door install turns into a second mobilisation; our guide to the rolling door Red Zone covers the clearances and how to get them signed off before the other trades rough in.
How do you protect a new door from forklifts?
Plan it with the slab. For rolling steel fire doors, where damage can stop the door closing in a fire, DASMA recommends guard posts, such as concrete-filled steel pipe rigidly secured to the floor or foundation, in front of each guide, and a heavy steel horizontal guard several feet in front of the opening with its bottom slightly below the top of the opening, so a raised mast or a high load hits the guard instead of the door. It also prefers face-mounted guides, because guides between the jambs narrow the opening and are more likely to be hit. A ceiling-hung guard needs a structural engineer. The same reasoning applies to any busy dock or drive-through door.
Source: DASMA Technical Data Sheet #290, Protecting Rolling Steel Fire Doors from Vehicular Traffic Related Damage (PDF). Checked 23 October 2026.What do we need from you to quote a new building?
- The door schedule, or the drawings with the openings marked: sizes, door types, fire ratings, and which doors are motor-operated
- The specified wind load, positive and negative, or the engineer who sets it
- The jamb construction at each opening: block, poured concrete, tilt-up with steel, or steel framing
- The supply voltage available at each powered door
- The date the openings will be framed and the date the doors are needed
- Whether dock levellers, seals and bumpers are in the same package
Send them through the quote form or by email to commercialgaragedoorman@gmail.com. Our published prices start a new commercial door from $5,000, varying with the size of the opening and the door specified; a new building is quoted in writing from the drawings.