Doors and screens
How to measure for a glass door panel
Glass in a door is safety-critical at any height below 1500mm under Approved Document K, and every hole in it is made before the glass is toughened. Both facts change how you measure.
Before you start
What you are measuring
The dimensions that decide the job
- The structural opening, width at three heights and height at both sides.
- The clearances the patch fittings, the floor covering and the head detail need.
- The position of every patch fitting, lock, handle and pull.
- Which way the door swings and what it clears when it does.
What to have in your hand
- A steel tape measure
- A spirit level
- The patch fitting manufacturer's data sheet
The printable measuring pack carries the record sheet these steps fill in, plus a tracing grid for shapes a tape cannot describe.
In this order
The steps, in the order the workshop takes them
Decide which job it is
A frameless glass leaf hanging on patch fittings is one job. A pane of glass going into an existing timber or metal door is another, measured to the rebate rather than to the opening. Say which one you have.
Measure the structural opening
Width at the head, the middle and the threshold; height at both jambs. Use the smallest width and the smaller height. An opening that is 6mm narrower at the bottom is common and fatal to a door cut to the top figure.
Allow for the floor covering
Measure the height to the finished floor, including the flooring still to be laid, and then take the gap the door needs to swing over it. A door measured to a bare screed will catch on the tiles.
Take the clearances the fittings need
Patch fittings, a floor spring and a head pivot each state the gap they occupy at the top and the bottom. Those figures come from the fitting's data sheet and are deducted from the opening to give the glass size.
Mark every fitting, lock and handle
Patch cut-outs, a lock keep, a handle pair and a pull each need a hole or a notch, and all of them are cut before toughening. Give the position of each from the same two edges, with the fitting's make and model.
Check the swing and the head detail
Which way it opens, what it clears as it swings, and whether there is an overpanel above it. A door and its overpanel are measured together, because the head detail between them is shared.
What we work to
The tolerance, and where to start
We cut to plus or minus 2mm, and every order is confirmed with a dimensioned drawing before anything is made. The clearance the patch fittings need is much larger and is what the door actually hangs on, so give us the opening and the fitting rather than a finished size you have worked out from both.
The usual specification
10mm toughened
10mm toughened for frameless internal doors.
The configurator link below opens with a frameless internal door at 800 x 2000mm in that specification. It is a starting point the workshop cuts often, not a guess at your opening: change the numbers to the ones you have just measured and the price and the drawing follow.
What costs people a panel
The common mistakes
Measuring the old door
The old leaf was cut for an opening that may have moved, and its fittings may not be the ones you are buying.
Forgetting the floor covering
The floor is the last thing laid and the first thing a door catches on. Measure to the finished level.
Ignoring the safety glass rule
Glass in a door below 1500mm from the floor is a critical location under Approved Document K. The safety check names the clause.
Ordering, then choosing the lock
Every cut-out is made before toughening. A lock chosen after the glass is made is a new piece of glass.
When you order
What to send us
- The three widths and the two heights of the opening, in millimetres.
- The floor finish and whether it is down yet.
- The patch fittings, floor spring, lock and handle, by make and model.
- Which way the door swings, and whether there is an overpanel or a side screen.
Write them on the record sheet as you go: download the three-page measuring pack PDF, or read the same sheets on the measuring pack page.
Next
Settle the rest before you order
- Whether the door needs safety glass
- The thickness a frameless door needs
- What the leaf will weigh on its hinges
Measuring something else? Every product we cut to size has its own guide on the measuring pack page.