Quick Summary

Von Duprin templates are the quiet part of an exit device order. Nobody asks for them until the device is on site, and by then the holes are often already in the door.

This guide covers what the templates actually govern, how to pick the right one, why function and handing change the pattern, and what to check before drilling anything.

What Is a Von Duprin Template and What Does It Specify?

It is the dimensioned drawing that locates the device on the door and the strike on the frame.

A template is not a general guide to fitting exit hardware. It is a specific set of dimensions for a specific device, giving the mounting height, the positions of every through hole, the cutouts needed for cylinders and trim, and where the strike has to sit so the latch engages it correctly.

Door and frame preparation is permanent. That is the whole reason templates exist: a hole in the wrong place on a steel door stays there for the life of the door.

Is a template the same as installation instructions?

No, and the two are often supplied separately. The instructions cover the sequence of assembly, the adjustments and the checks. The template covers the geometry. You can follow instructions perfectly and still have a device in the wrong place if the template was never used. Our exit device installation guide covers the sequence side of it.

Which Template Do You Need for Your Device?

Four pieces of information select it, and all four come off the opening and the order rather than out of a catalogue.

If the series is not known, that is the first thing to settle rather than the last. Our Von Duprin series guide covers how the ranges are distinguished, and the selection guide covers how a series is chosen in the first place.

Does the device length change the template?

It changes the mounting dimensions along the door, because the device has to be centred on the leaf and the end cap has to land somewhere sensible. A device sized for one door width fitted to a narrower leaf will not place its fixings where the template expects, which is why device length is confirmed against the leaf rather than assumed from the old device.

Why Does the Device Function Change the Template?

Because function adds hardware, and hardware needs holes.

A plain mechanical device needs the baseplate fixings and the latch arrangement. Add cylinder dogging and the door needs a cutout for the cylinder. Add outside trim and the door needs the trim fixings and the spindle or tailpiece hole. Add electrification and the door needs a route for conductors, which usually means a transfer position as well.

Each of those additions is a different drawing, not an annotation on the same one. A device ordered with electric latch retraction and fitted to a door prepped for a mechanical device will be short of at least one hole.

What about conversion kits?

Conversion kits exist precisely because the hole pattern is the expensive part. A kit that converts a device from one dogging type to another, or adds motorised retraction, is designed to work within the preparation that is already there wherever possible. Our conversion kit parts guide covers one of the common examples.

How Does Handing Affect the Hole Pattern?

It mirrors it. Everything that was on the left is now on the right.

Handing describes which edge of the door the hinges are on and which way the leaf swings. On an exit device it determines which end of the rail carries the latch and which carries the end cap, and therefore where every asymmetric feature sits.

The failure mode is unforgiving. A template read for the wrong hand produces a door with the latch cutout at the hinge end. There is no adjustment that recovers from that.

How do you establish handing before ordering?

Stand on the outside of the door, the side you would need a key for. If the hinges are on your right and the door opens away from you, it is one hand. If they are on your left, it is the other. Write it down at the opening rather than reconstructing it later from memory.

On a pair of doors, hand each leaf separately. The two are not the same, and one of the most common ordering errors on pairs is applying one hand to both. Our mullion guide covers the related decisions on pairs.

What Does the Template Say About Reinforcement?

Where the fixings need something solid to land in.

Exit devices concentrate load at the center case and at the latch end. On a hollow metal door, that load needs internal reinforcement at the right positions, and the template is where those positions are defined. On a timber door, the equivalent question is whether the fixings are reaching solid material or just the skin.

This is the part of the drawing that gets skipped most often, because the consequence is delayed. A device fixed into unreinforced skin works perfectly on the day and loosens over the following months.

Does the frame need preparation too?

Yes, and it is easy to forget when the attention is on the door. The strike position is part of the template, the frame may need reinforcement behind it, and on a mullion arrangement the mullion fixings at head and sill are part of the same drawing.

Can You Fit a New Device to an Existing Door Prep?

Often, and that is what retrofit kits are for. The question is whether the existing holes match what the new device needs.

Retrofit works when the replacement device shares enough of the original pattern that the existing holes can be reused, with any extras drilled and any surplus covered. It stops working when the two patterns differ in the centreline height or in the latch position, because those cannot be hidden.

How do you record an existing prep?

Measure from fixed references and photograph with a tape in shot. Record the centreline height from the floor, the distance of each hole from the latch edge and from the floor, the diameter of each hole, and the cutouts for any cylinder or trim.

That record is what lets a supplier tell you whether a given device will land on the holes that exist. A description of the old device is not enough, because two devices from the same series can have been prepped differently depending on their function.

What Goes Wrong When the Template Is Ignored?

The pattern across all five is that the cheap errors reveal themselves immediately and the expensive ones do not. Reinforcement and strike position are the two that will be somebody else's call out.

Does a fire rated opening change anything?

It raises the stakes considerably. A rated assembly is tested as a set, and site drilling beyond what the hardware listing allows can take the opening outside what was certified. Templates matter more here, not less. Our fire rating guide covers what is permitted on a rated assembly.

How Do Templates Differ Between Door Types?

Mostly in what the fixings land in and what the latch end has to reach.

A hollow metal door needs reinforcement positions defined. A timber door needs fixings that reach solid material rather than veneer. An aluminium stile door is dimensionally constrained by the stile width, which limits what will fit at all. A glass door with a rail at top and bottom limits the mounting position to the rail.

Those constraints are why the door material is one of the four inputs that selects the template rather than a detail.

What changes on a concealed vertical rod device?

Everything inside the door. A concealed rod device routes rods through the leaf to latch at the head and the sill, so the preparation is internal rather than only through the face. That makes retrofitting one far more involved than retrofitting a rim device, and it makes the template non negotiable. Our concealed vertical rod guide covers the configuration in detail.

What Should You Check Before Drilling?

Five things, in this order, and all of them before the drill is picked up.

That the template matches the exact device on the bench, including its function. That the hand is right, confirmed at the door rather than from the paperwork. That the centreline height clears the closer arm, any glazing and any existing trim. That the fixings have something to land in. And that the strike position on the frame has been marked as part of the same exercise rather than left until the device is on.

What if the device has not arrived yet?

Then do not drill. The number of openings prepped from a template for the device that was ordered and then fitted with the device that was delivered is not small. Confirm the device in front of you against the drawing in your hand, every time.

For a worked example of how a template governs a different category of hardware, our door closer installation template guide covers the same principles applied to closers, and the 98 and 99 Series parts guide covers the components that the pattern has to accommodate.

About the Author

Security Parts has supplied repair parts for commercial door hardware since 2001, covering Von Duprin, LCN, Schlage, Falcon, Detex and Adams Rite at the component level. Our diagram based lookup exists so a technician can confirm a part before ordering it. This guide was written by the Security Parts team from supplier documentation and the questions our customers bring us.