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Quick Verdict

An overhead door stop mounts on the door's top rail and the frame head and absorbs the door's momentum at 85 to 110 degrees, before the closer arm, hinges or wall take the hit. Mount: surface (Glynn-Johnson 90 and 450, Rixson 9, 10, 55 and 8 series) for retrofits; concealed (Glynn-Johnson 100 and 410, Rixson 1 and 6) for new doors, double-acting doors and aluminum storefront. Function: stop-only (S) is the only mechanical function allowed on a fire door; hold-open (H) and friction (F) go on non-rated doors; a rated door that must stay open gets a stop-only overhead plus an electromagnetic holder (Rixson 998M, LCN SEM7850) released by the fire alarm. Size: by leaf width, not opening width; a 36" door on butt hinges takes Glynn-Johnson size 4 or a Rixson -336. Heavy-duty for exterior, entrance and abuse doors; medium or standard duty for interior office doors.

What an overhead door stop does that a floor stop or a closer cannot

A floor or wall stop catches the door at one point near the lock edge, far from the hinge line; on a heavy door at speed that racks the leaf, loosens hinge screws and shears the stop off the slab. An overhead stop takes the load at the top rail, in line with the door's arc, through a shock absorber spring: Rixson's 1, 6, 9 and 55 series compress 5 to 7 degrees before dead stop (6 degrees on the 8-336), and Glynn-Johnson's stop-only models keep the full shock-absorbing capacity of the hold-open versions. A kick-down holder such as the Ives FS455 is a hold-open for non-rated interior doors, not a stop. Where a floor, wall or dome stop is still the right call, see the guide to commercial door stops for heavy doors.

A closer is a speed control, not a stop. Its mechanical limit is the arm geometry, and every time the door bottoms out on the arm the shock runs back through arm, shaft and pinion: bent arms on wind-loaded exterior doors, closer bodies pulling their screws on cart-traffic doors, doors slamming into sidelights with no wall for a wall stop. An overhead stop catches the door at the templated angle before the arm reaches its limit; whether a dead-stop cush arm changes that is covered in the sibling guide to door closer arm types and mounting options. It also sets the swing: 85 to 110 degrees on Glynn-Johnson templates, 110 maximum on Rixson, with no wall needed behind the door.

Surface-mounted vs concealed overhead stops: which one for this door

Surface models (Glynn-Johnson 90 and 450, Rixson 9, 10, 55 and 8) put the channel on the door face, fastened with sex bolts or thru-bolts, and the jamb bracket on the frame. Minimal prep makes surface the retrofit answer on existing hollow metal or wood doors. Every surface model here is single-acting only.

Concealed models (Glynn-Johnson 100 and 410, Rixson 1 and 6) mortise the channel into the top rail and the jamb bracket into the frame head; closed, nothing shows. They handle single- or double-acting doors, which is why they pair with center-hung pivots (see the sibling guide to floor closers and pivots). Rixson's 1-336 needs a 1-3/4" minimum door and a 1-3/16" square channel pocket; the low-profile 6-336 fits the narrow top rail of aluminum storefront doors with a channel 1-1/4" wide by 1/2" deep. Order concealed stops with the door so the pocket is cut from the template.

Rixson surface stops template to the push side by default; pull-side mounting, or a flush or rabbeted push-side frame, needs the angle jamb bracket adapter: 5258 on the 10 and 55 series, the handed 5458-LH or 5459-RH on the 9 series. The 8-336 cannot be mounted on the pull side at all. Glynn-Johnson's 100 and 450 templates cover butts, offset pivots, continuous and swing-clear hinges; the 90 and 410 cover butts and specialty hinges.

Materials track exposure: Glynn-Johnson 90 and 100 (300 series stainless or brass; steel on the 90) and Rixson 1, 6 and 9 are rated interior or exterior; Glynn-Johnson 450 and 410 and Rixson 10 and 55 are interior only; the 8-336 is stainless base metal only. Rule: existing single-acting door, surface; new door, double-acting, storefront, or a channel the architect must not see, concealed.

Overhead stop functions decoded: S, H, F and selective hold-open

The function letter follows the size number on Glynn-Johnson models and decides whether the unit is legal on a fire door.

• S, stop only. Rixson's stop models are ANSI/BHMA A156.8 Grade 1 certified and UL listed for fire door assemblies; Glynn-Johnson states the stop-only model may be used on fire doors. Default for rated openings and for doors that already have a hold-open closer arm.

• H, hold-open. Holds at the templated angle until someone pulls the door closed. Non-rated doors only: NFPA 80 requires a rated door to self-close, and the walk-through in the NFPA 80 fire door inspection guide flags mechanical hold-opens on sight.

• F, friction hold-open. Adjustable friction holds the door anywhere in its swing. Non-rated doors only.

• Selective hold-open. A switch on the channel turns the hold-open on or off. Non-rated doors only.

Glynn-Johnson's 90 and 100 series offer function conversion kits, so a stop-only unit can become a hold-open later without new door prep. Rixson encodes function in the model number: on 9-336, 9 is the series, 3 the size and 36 the stop-only function; 9-436 is the same stop one size up. Hold-open Rixson units carry a different ending.

Sizing an overhead stop by door width: Glynn-Johnson sizes and Rixson series

Size by leaf width and hanging means. Butt hinges and offset pivots share one bracket; center-hung pivots put the pivot further into the door and move the same leaf into the next bracket. Every model below is non-handed and tops out at 110 degrees.

Model	Mount	Duty	Width, butts/offset pivots	Width, center-hung	Acting	Exposure
Glynn-Johnson 902S	Surface	Heavy	23-1/16" to 27"	27-1/16" to 33"	Single	Int/Ext
Glynn-Johnson 903S	Surface	Heavy	27-1/16" to 33"	33-1/16" to 39"	Single	Int/Ext
Glynn-Johnson 904S	Surface	Heavy	33-1/16" to 39"	39-1/16" to 45"	Single	Int/Ext
Glynn-Johnson 906S	Surface	Heavy	45-1/16" to 51"	51-1/16" to 59"	Single	Int/Ext
Glynn-Johnson 104S	Concealed	Heavy	33-1/16" to 39"	39-1/16" to 45"	Single/double	Int/Ext
Glynn-Johnson 454S	Surface	Medium	33-1/16" to 39"	39-1/16" to 45"	Single	Interior
Glynn-Johnson 414S	Concealed	Medium	33-1/16" to 39"	39-1/16" to 45"	Single/double	Interior
Rixson 1-336	Concealed	Heavy	33-1/16" to 38"	36-1/16" to 41"	Single/double	Int/Ext
Rixson 6-336	Concealed, low profile	Heavy	33-1/16" to 38"	36-1/16" to 41"	Single/double	Int/Ext
Rixson 9-336	Surface	Heavy	33-1/16" to 38"	36-1/16" to 41"	Single	Int/Ext
Rixson 9-436	Surface	Heavy	38-1/16" to 43"	41-1/16" to 46"	Single	Int/Ext
Rixson 10-336	Surface	Standard, adjustable	30-1/16" to 36"	32-1/16" to 38"	Single	Interior
Rixson 55-336	Surface	Standard, fixed	30-1/16" to 36"	32-1/16" to 38-1/2"	Single	Interior
Rixson 8-336	Surface, push side only	Extra heavy	32-9/16" to 38-3/4"	35-1/16" to 42-1/2"	Single	Int/Ext

Common cases:

• 36" on butts, exterior or high traffic. Glynn-Johnson 904S surface at about $229 at NLS, or Glynn-Johnson 104S concealed at about $356 at NLS; on the Rixson side, the 9-336 surface stop or the 1-336 concealed stop.

• 36" on butts, interior office or classroom. Glynn-Johnson 454S surface, Glynn-Johnson 414S concealed, or a Rixson 10-336 at about $178 at NLS when the angle is set after hanging.

• 36" on center-hung pivots. Glynn-Johnson drops to size 3 (903S). Rixson's -336 center-hung bracket starts at 36-1/16", so ask the desk for the next size down.

• 42" on butts. Above Glynn-Johnson size 4; Rixson 9-436 covers 38-1/16" to 43". A 48" leaf takes Glynn-Johnson 906S.

Duty follows the door: heavy-duty (Glynn-Johnson 90 and 100, Rixson 1, 6 and 9) for entrance, vestibule and exterior doors and interior doors that meet carts or gurneys; medium or standard (Glynn-Johnson 450 and 410, Rixson 10 and 55) for medium-weight interior doors; extra heavy (Rixson 8-336, double lever design) where a heavy-duty unit has already been replaced once. Rixson requires special templating and pricing for any hanging means other than standard butts or offset pivots. Mount, function and size together:

Situation	Stop type	Function	Suggested model
Existing 36" exterior door, wind	Surface, heavy-duty	S	Glynn-Johnson 904S or Rixson 9-336
New 36" entrance door, channel hidden	Concealed, heavy-duty	S	Glynn-Johnson 104S or Rixson 1-336
Aluminum storefront door, double-acting	Concealed, low profile	S	Rixson 6-336
Interior office door, stop angle set on site	Surface, standard duty	S	Rixson 10-336
Interior office door, hidden channel, budget	Concealed, medium duty	S	Glynn-Johnson 414S
Non-rated delivery door parked at any angle	Surface, medium duty	F	Glynn-Johnson 450 series, F
Fire-rated corridor door held open	Surface, heavy-duty	S plus magnet	Glynn-Johnson 904S with Rixson 998M
Loading door, heavy abuse, push side	Surface, extra heavy-duty	S	Rixson 8-336

When an electromagnetic door holder beats a hold-open overhead stop

Any door that must stay open in service and close by itself in a fire is a magnetic holder job, not an H or F function. NFPA 80 and NFPA 101 allow a rated door to be held open only by a device that releases on fire alarm or smoke detection and lets the closer finish closing and latching. Hospital cross-corridor, smoke barrier and school corridor doors get the same package: stop-only overhead plus a fail-safe magnet wired through the fire alarm relay, holding while powered and dropping the door the instant current is cut.

• Rixson 998M: wall mount, concealed wiring, 3-5/8" projection, 2" x 4" x 1-3/4" outlet box, ANSI/BHMA A156.15 Grade 1, about $485 at NLS. The 999M is the universal-mount version (4-3/8" projection); the 900-300 (3") and 900-700 (7") spacers extend the 900 base unit when the open door stops short of the wall.

• LCN SEM7850: recessed wall mount, standard profile armature (SEM7840 is low profile), tri-voltage, 35 lbs holding force, UL listed for smoke barrier or labeled fire doors, ANSI A156.15, external doors 24" to 48" and internal doors to 60".

Both require a reinforced wall and an outlet box fastened to structure. The overhead stop still goes on, set a few degrees beyond the magnet contact angle so the door reaches the armature; it protects the magnet when the door is thrown open with power off.

Coordinating the overhead stop with the door closer

Degree of opening. The closer arm has a mechanical maximum that depends on arm type and mounting; template the stop at or short of it so the stop, not the arm, takes the door. Rixson's 10-336 is the only unit in the table with a field-adjustable angle; the 55-336 and every Glynn-Johnson model fix it by template position, so decide the angle on paper before drilling.

Hold-open: pick one. A hold-open closer arm plus an H-function overhead is two hold-opens fighting at different angles. Stop-only overhead with a hold-open closer, or hold-open overhead with a standard arm, never both; on a fire door neither is permitted. Closer types, grades and hold-open arms are laid out in the door closers explained guide.

Arm and channel conflict. A parallel-arm closer sits on the push side with its arm shoe on the frame soffit, exactly where a push-side surface stop wants its jamb bracket. The closer body drops below the stop channel and shoe and bracket are positioned per both templates; a regular-arm closer on the pull side projects from the frame face above the channel. Glynn-Johnson rates all four series for most surface-applied closers; when in doubt send both model numbers to the desk for the combined template. Set backcheck to start before the stop angle so the stop's spring absorbs residual energy, not the full swing.

Common mistakes with overhead door stops

1. Sizing by the frame opening instead of the leaf. Measure the door; on center-hung pivots read the second column.

2. Hold-open on a fire door. H and F functions fail the NFPA 80 inspection. Stop-only plus an alarm-released magnet.

3. Letting the closer arm be the stop. Arm, shaft and pinion take the shock. Template the stop inside the arm's limit.

4. Stop angle short of the magnet. Overhead at 90, magnet contact at 95: the door never touches the armature.

5. Wrong side without the adapter. Rixson pull-side or flush push-side mounting needs the 5258 or the handed 5458-LH/5459-RH adapter; the 8-336 is push side only.

6. Rixson heavy-duty on a thin door. The 1-336, 6-336, 9-336 and 8-336 all require a 1-3/4" minimum door.

7. Medium or standard duty outdoors. Glynn-Johnson 450 and 410 and Rixson 10 and 55 are interior only.

FAQ

Can an overhead door stop go on a fire-rated door?

Yes, in stop-only function: Rixson's stop models are UL listed for fire door assemblies and Glynn-Johnson's 90S, 100S, 450S and 410S may be used on fire doors. Hold-open and friction functions are not permitted on rated doors; use an alarm-released electromagnetic holder instead.

What size overhead stop does a 36-inch door need?

On butts or offset pivots, Glynn-Johnson size 4 (33-1/16" to 39") or a Rixson -336 (33-1/16" to 38"). On center-hung pivots, Glynn-Johnson size 3; for Rixson, 36" sits just under the -336 center-hung bracket, so ask for the next size down.

Glynn-Johnson or Rixson?

Both are non-handed, top out at 110 degrees and are listed for fire doors in stop-only function, so pick by feature. Glynn-Johnson offers more size brackets per series, function conversion kits and standard templates for continuous and swing-clear hinges; Rixson offers the field-adjustable 10-336, the storefront-specific 6-336 and the double-lever 8-336.

Do I still need an overhead stop if the closer has a dead-stop (cush) arm?

For interior doors of normal weight, usually not. On wind-exposed exterior doors, doors over 42" and cart-traffic doors, the overhead stop takes the primary hit and the cush arm becomes the backup.

Next step

Measure the leaf, note the hanging means and mounting face, then pick from the overhead door stops and holders category. For a 36" door on butts, the Glynn-Johnson 904S is the surface answer and the 104S the concealed one; fire-rated doors that must stay open get a stop-only unit plus the Rixson 998M on the fire alarm relay. Orders placed before 3:00 p.m. EST ship the same day from the Brooklyn, NY warehouse by UPS or FedEx, ground shipping is free at $450 and up, and stock items return within 30 days in saleable uninstalled condition. For combined templates, non-standard hanging means or unlisted sizes, call the commercial desk at 718-814-6300 with door width, thickness, hinge type and closer model.