Garage Door Headroom Measurement: Minimum Clearance

The space between the top of your door opening and the nearest obstruction (ceiling) is known as headroom. Although the ceiling is most commonly used, other obstructions like support beams, lights, pipes and ducts must be factored in.

  • The minimum required space for standard residential garage door torsion spring configurations is 12″ for manual operation and 15″ for automatic openers applications. 
  • The minimum required space for standard commercial garage door torsion spring configurations is 15″ for manual operation and 18″ for automatic openers applications.
  • The minimum required space for industrial overhead doors can range from 24″ to 36″ depending on the radius of the horizontal track or the diameter of the barrel for rolling steel applications.

Most people want to know the minimum headroom needed although best practice is to leave yourself plenty of extra space to give yourself the flexibility for larger radius tracks and (drawbar) opener installation. Openings with less than the minimum recommended headroom must have different spring and track configurations installed.

Most people forget about minimum garage door headroom requirements when planning for new overhead doors. Before framing an opening or replacing an existing garage door always measure the space between the top of the door frame and the nearest obstruction. In most cases this is the ceiling, but obstructions below the ceiling can also come into play. Measuring and planning for the proper amount of headroom before framing in an opening will save you time and money.

In my years in door sales there was always a high number of people who would purchase doors without accounting for headroom requirements – despite our prior warnings. This often involved long trips back to our warehouse to exchange hardware, restocking fees and even framing down openings. Do yourself a favor and be pro-active in figuring out the necessary clearance for the door you intend to install. Always plan and measure your door headroom before ordering or installing overhead doors and openers.

 

Measuring Garage Door Headroom

Determining the amount of space you currently have above your door opening is easily accomplished using a tape measure. Simply measure from the top frame of your door opening to the nearest obstruction (ceiling). If you have a tall door opening you may need a ladder or laser tape measure.


If you know the existing garage door opening height you can measure headroom another way. Take a floor to nearest obstruction measurement and subtract your known or desired door height. This is a convenient method if you don’t have a ladder and are dealing with a tall door.

Be on the lookout for hidden obstructions since they count toward your total headroom figure. For residential applications the ceiling is usually going to be a headroom measuring point, but certain commercial applications  and pole barns commonly have obstacles to account for. Since your door curves just above the opening and rolls back away from the opening any obstructions within the door path should be accounted for. Here are some common obstructions you will need to account for.

Types Of Headroom Obstructions

  • Steel Beams
  • Drop Ceiling
  • Piping
  • Air Ducts
  • Sound Systems
  • Sprinkler Head
  • Shelving
  • Storage Racks
  • Lights
  • Electrical Conduit
If any obstruction is in the path of the garage door during operation it must be accounted for. In the rare case of multiple obstructions below the ceiling you will need to use the nearest one in measuring. In cases where obstructions like steel beams are in the way, you may be able to run the door over the obstruction. In any case a great deal of planning needs to be done first to ensure your door will run smoothly.

Minimum Torsion Spring Headroom

Most people have torsion hardware installed on their garage doors. The torsion hardware “spring line” is composed of end bearing plates, drums, center plate, solid shaft and torsion springs. Torsion hardware is superior to extension hardware in that the system is balanced, but the hardware also takes up space above the door.

The other factor coming into play is the radius of the door track. Standard garage door track comes with 12″ Radius. That is a measure of the curvature of the track radius. Residential doors typically use either 10″ Radius or 12″ Radius track, although they can also be ordered with 15″ Radius for smoother operation. If your garage door has sections that are 21″ tall and under then 12″ Radius track is sufficient. However, garage doors with 24″ sections and greater should use 15″ Radius track or higher.

Torsion Spring Headroom Chart

Door Height2" Track 10" Radius2" Track
12" Radius
2" Track
15" Radius
3" Track
15" Radius
0'- 12'10 inches12 inches15 inches15 inches
12'3" -16'N/A15 inches16 inches16 inches
16'3"-18'
N/AN/AN/A16 inches
Over 18'N/AN/AN/A21 inches

The above chart is intended for manual lift door configurations. If you intend to use an automatic garage door opener with a drawbar you would need to allow an additional 2″-3″ of additional headroom. The height of the operator rail will vary by manufacturer.

If you have less space than recommended you still may be able to install a door, but you may require different track and spring configurations – low clearance track, extension or rear torsion springs.

 

10″ Radius Track Headroom Required

  • Standard Track Manual Operation (Torsion Springs) – 10 inches headroom minimum

  • Standard Track Using Garage Door Opener (Torsion Springs) – 13 inches headroom minimum

12″ Radius Track Headroom Required

  • Standard Track Manual Operation (Torsion Springs) – 12 inches headroom minimum

  • Standard Track Using Garage Door Opener (Torsion Springs) – 15 inches headroom minimum

15″ Radius Track Headroom Required

  • Standard Track Manual Operation (Torsion Springs) – 15 inches headroom minimum

  • Standard Track Using Garage Door Opener (Torsion Springs) – 18 inches headroom minimum

 

Manual operation means you are opening and closing the garage door by hand without the use of an automatic opener. If you plan on installing an operator you must add 3″ to your headroom requirement, because the operator rail and motor will take up 3″ of space over the top of the torsion spring line.

Low Headroom Clearance Track

Options are available to cut down the recommended clearance figures above. Door manufacturers have come up with low headroom “low clearance” track to help the door curve away from the opening and ceiling faster. Low headroom track has a double channel system with the top rollers operating in the top channel and  other rollers using the bottom track channel. Flat bottom brackets and outside hookup bottom fixtures are also required for this type of assembly. Here are some basic low clearance track figures.

12″ Radius Track Headroom Required
  • Low Headroom Front Mount Manual Operation (Torsion Springs) – 9 inches headroom minimum

  • Standard Track Front Mount Garage Door Opener (Torsion Springs) – 12 inches headroom minimum

15″ Radius Track Headroom Required
  • Low Headroom Front Mount Manual Operation (Torsion Springs) – 12 inches headroom minimum

  • Low Headroom Front Mount Garage Door Opener (Torsion Springs) – 15 inches headroom minimum

 

Low Headroom Rear Mount Torsion & Extension Spring

You are probably use to torsion springs being installed right above the garage door, but did you know they can also be installed at the back of the horizontal tracks? This application is called rear mount torsion low headroom and is used in situations with extremely low headroom available. The same can be said for low headroom track using extension springs – low headroom extension. Here are the minimum requirements for both setups.

12″ Radius Track Headroom Required
  • Low Headroom Rear Mount Torsion Manual Operation (Torsion Springs) – 4 inches headroom minimum

  • Low Headroom Rear Mount Torsion Garage Door Opener (Torsion Springs) – 7 inches headroom minimum

  • Low Headroom Extension Springs Manual Operation (Torsion Springs) – 4 inches headroom minimum

  • Low Headroom Extension Springs Garage Door Opener (Torsion Springs) – 7 inches headroom minimum

 

There are some downsides to using low clearance low headroom track. Cost is a factor as special hardware and different dual channel track is used. This increases the cost of the door kit by 10%-15% when purchased as an upgrade. Purchasing a conversion kit after originally  ordering standard lift can run in the hundreds of dollars.

The second downside of using low clearance track is the limitation of openers that can be used. Side mount jackshaft operators such as the Liftmaster 8500W, 3800 and 3900 cannot be used on torsion low headroom applications or extension spring systems. When low headroom torsion springs are installed they are wound backwards which goes against the mechanism of side mount openers. Extension springs are also not compatible due to the springs being an unbalanced system. Jack shaft operators would pull the door up unevenly causing the door to tilt side to side in the opening.

 

Garage Door Opener Headroom Required

Be sure to account for about 3″  of space for your opener rail to be mounted to the header. Most residential opener rails measure 2 1/2″ in height with some “I” beam rails 3″ in height. Again, side mount jack shaft openers cannot be mounted on doors using low headroom track kits. Commercial trolley operators may require even more space as the rails often measure 4″ – 5″ in height. Before framing in your opening allow yourself additional space for an optional opener.

 

Quick Turn Brackets

In the unfortunate event you have framed your door opening with less headroom than manufacturer specifications you still have a few options. The easiest option is to install a special type of top fixture called a quick turn or quick close bracket. These brackets are sold in pairs and mount to the top right and left side of your door in place of the normal triangular fixtures.

Quick close brackets are the first option you should turn to for minor headroom issues. They generally will provide about 2 1/2″ of headroom space savings. If your garage door won’t turn around the radius by a matter of inches these brackets will be an easy solution. The brackets allow your top panel to turn around the track radius quicker. The fixtures are composed of a long anchor base and built-in hinge. I sell them in my online store in pairs and rollers are included – Quick Turn Bracket

Quick Turn Bracket
Quick Turn Brackets

 

These brackets are installed in place of your normal top fixtures and are solid as a pair. The brackets also include two standard nylon garage door rollers. Self drilling TEK screws are required to fasten the brackets to your garage door end stiles. The brackets can be adjusted up or down on each end stile.

 

Low Headroom Conversion Kits

Standard garage doors come with single channel track, angled top fixtures and inside hookup bottom brackets. If your garage door is currently standard lift and you need to convert to low headroom you will need to order special parts. Low headroom conversion kits can be difficult to locate online. The main problem is that the dual channel track can be difficult to ship economically due to the size.

Extension Spring Conversion Kit

 

Rear Torsion Conversion Kit

End Bearing Plates

Longer Cables

 

Garage Door Headroom Chart

3″ Commercial & Industrial Heavy Duty Track

Commercial and industrial doors are sometimes extremely large sizes and weights. Because of this they require heavier gauge steel and thicker track. The increased size of the track and radius also increase headroom requirements. Industrial doors are heavy enough that they cannot be lifted comfortable by hand with the use of chain hoists. Industrial grade operators are almost mandatory on large sectional doors.

  • 3″ Track Using Garage Door Using Opener (Torsion Springs) –  36″ inches headroom minimum

 

Roll-up Barrel Style Door Headroom (Janus & DBCI)

  • Dependent on door height since barrel diameter increases based on door height.
  • Residential Size Rollup Doors 18″ Recommended
  • Commercial Size Rollup Doors 24″ – 36″

Always consult manufacturer headroom specifications before ordering or installing any door.

 

Rollup style overhead doors that roll up into a barrel have specific headroom requirements also. Unlike sectional garage doors that have somewhat fixed recommendations based on track radius and door height, sheet doors vary based on height. As the height of a roll up door increases the barrel size also increases to a maximum point. Residential sheet doors like you would find on a mini storage facility can almost always fit in 18″ of headroom. Commercial and industrial doors can vary widely, requiring 24″ and more on occasion.

What if my opening is under 3″ of headroom?

If the opening you are looking at has 3 inches or less headroom you must frame down the opening to accommodate a smaller door height. Always plan your opening for the proper amount of headroom as it will save you time and money. Leaving 18″ of headroom is always best when planning for overhead sectional doors. This leaves enough space for commercial size garage door panels and most types of automatic door openers. This also leaves the option for adding an opener to a manual lift door later on. Lastly, if gives you the option of installing a rollup barrel style door as well.

If all other possibilities above are exhausted and you need a door to fit in the opening there is still one option – cutting the bottom of each vertical track as a last resort. However, you must realize that you can only cut 2-3″ off and doing so will drop the bottom of the bottom section into the opening equally with the door in the raised position. Why does this matter? If you are trying to fit a vehicle or tractor into an opening the bottom section of the door will hang down into the opening equally to the amount of track you cut off. You may not have enough space to fit what you need in the garage. Garage door springs and track angle are also negatively affected by using this method as springs and track are calibrated for specific door heights. Never cut more than 2-3″ off the bottom of your vertical tracks.

Headroom is an overlooked aspect of the garage door installation, ordering and planning process – especially when replacing barn slider style doors.  Most homeowners want the maximum height garage door possible in an opening. As a general rule it is almost always best to leave 18″ of headroom space above the door. If you feel like every inch counts to try to get a vehicle or specific equipment in the garage consult your local door professional. Door professionals can literally lay out all of the track and hardware on the ground and calculate exactly how much door you can comfortable fit. Most companies offer free on  site consultations for these circumstances.