What Counts as a Heavy Door?
Most standard commercial doors weigh well under 150 lbs. Heavy doors are another category: they carry more momentum, stress hinges and arms more, and need more spring force to latch. Typical examples:
- Solid wood and solid-core doors, especially oversized church and lobby entrances.
- Lead-lined doors for X-ray and imaging rooms, which can be very heavy for their size.
- Acoustic (STC-rated) doors in auditoriums, studios and music rooms.
- Heavy-gauge steel doors in plants, stair towers and back-of-house corridors.
- Wide doors of 48" or more for beds, equipment and crowd egress.
Weigh the slab or use the door manufacturer's data rather than guessing; estimates are often far off for solid and lined doors.
Sizing a Door Closer for Heavy and Wide Doors
Closer size (1 to 6) describes spring power. Heavy and wide doors usually need size 5 or 6, and you should size up one more level for exterior exposure, parallel arm mounting or heavy seals. The DRIWON DN-9500 is adjustable across the full range, so the same model covers the heaviest openings in a building. Set backcheck firmly: on a heavy door it protects the frame, the wall and the arm from the door's momentum.
Important: a closer does not carry the door's weight. Heavy doors need heavy-weight hinges, continuous hinges or pivots rated for the load. If a door sags or rubs, fix the hinges before adjusting the closer.
Pairs of Heavy Doors
Double doors use one closer per leaf. If the pair has an overlapping astragal, a coordinator is needed so the inactive leaf closes first; otherwise the doors can jam and fail to latch, which is a fire code problem on rated pairs.
Heavy Doors and Accessibility
A heavy door can be made to close reliably, but it may not open within the 5 lbf ADA limit for interior non-fire doors. Where the force cannot be met, add a low-energy automatic operator on the accessible route and keep the closer for the self-closing function.
Related: cast iron door closers, the door closer size chart, and heavy-door industries such as churches, theaters and auditoriums and medical imaging suites.
DRIWON DN-9500 Specifications
| Model | DRIWON DN-9500 extra heavy duty commercial door closer |
|---|
| Certification | ANSI/BHMA A156.4 Grade 1; UL listed |
|---|
| Fire rating | 3-hour fire rated when installed on a rated door assembly |
|---|
| Power size | Adjustable 1–6 |
|---|
| Door weight | 44–440 lbs (20–200 kg) |
|---|
| Door width | 23"–59" (58–150 cm) |
|---|
| Body / arm | Extra heavy duty cast iron body, wrought steel arm, heat-treated piston |
|---|
| Control | Hydraulic, with delayed action and secure positive latch |
|---|
| Finish | Corrosion-resistant powder coat, silver or black |
|---|
Need the lighter-duty option for interior doors? See the DRIWON DN-8220 Grade 1 door closer. Full details on the DN-9500 product page.
