Full overlay vs half overlay sounds like a finish option. It is actually a cutting instruction, and the two words mean different geometry depending on which side of the Atlantic your buyer learned them. Send "full overlay doors for a 24-inch cabinet" to two factories and you can get back two doors 9.5 mm apart in width — both correct, one unusable.
Here is the arithmetic that produces that gap, because it is the whole problem in one line. A 24-inch face-frame cabinet with 1-1/2 inch stiles has a 21 inch opening; the US convention for full overlay is a 1-1/4 inch overlay, so the door is 21 + 2 × 1.25 = 23-1/2 inches. A 24-inch frameless cabinet has no frame, so a full overlay door covers the box edge to edge minus the standard 1/8 inch reveal: 23-7/8 inches. Same phrase, same cabinet width, 3/8 inch — 9.5 mm — of difference.
Full Overlay vs Half Overlay: The Two Vocabularies
Overlay is a face-frame word: it states how much of the cabinet frame the door covers. Zero overlay means the door exactly fills the opening and hides none of the frame.
Reveal is a frameless word: it states how much of the cabinet edge stays visible. Zero reveal means the door is flush with the outside of the box.
They describe the same joint from opposite ends, which is why an order that mixes them is unbuildable without a phone call.
| Face frame (North American) | Frameless (European / 32 mm) | |
|---|---|---|
| Word used | Overlay | Reveal |
| Measured from | Edge of the opening outward | Outside of the box inward |
| Reference part | Frame stile, typically 1-1/2 in (38 mm) | Side panel, typically 16 or 18 mm |
| Standard values | 1/2 in and 1-1/4 in overlay; 5/8 in and 1-3/8 in also sold | 1/8 in (3 mm) reveal between doors |
| "Full" means | A large overlay that still leaves a reveal | The door covers the panel edge |
| Door size formula | Door = opening + 2 × overlay | Door = box face − reveal allowance |
Two further terms get scrambled in the same emails:
- Half overlay is not "half of full overlay." It is the hinge and door arrangement for two doors sharing one partition, each covering roughly half of it — 8 mm each on a 16 mm frameless partition. A cabinet can be full overlay on its outer edges and half overlay at a shared centre panel in the same carcass.
- Inset is not an overlay at all. The door sits inside the opening. Showplace Cabinetry specifies 3/32 inch clearance around an inset door, with the full 1-1/2 inch frame visible.
Scenario A: The Buyer's Cabinets Are Frameless
This is most of Europe, most of Australia, and the majority of flat-pack and imported kitchen work everywhere else.
What to confirm before cutting:
- Panel thickness — 16 mm and 18 mm are both common and they change every door width in the run.
- Reveal between doors — 3 mm is the default; some programmes run 2 mm for a tighter look.
- Whether the run ends against a wall, a filler or an end panel, which changes the outer reveal.
Door width for a single full-overlay door on a 600 mm box with 3 mm reveals: 600 − 3 = 597 mm. For a pair on the same box: (600 − 3 centre gap − 0) ÷ 2 = 298.5 mm each.
The trap here is the buyer who says "full overlay" and means "zero reveal." Zero reveal doors touch when they swing. Glass and mirror doors need more room, not less — Blum's technical catalogue recommends a minimum 2 mm surrounding gap for glass and mirror fronts because of breakage risk.
Scenario B: The Buyer's Cabinets Are Face Frame
This is the North American residential market, and the one that generates the most rework, because the word "full" is genuinely contested inside the trade.
A long-running WoodWeb discussion among professional cabinetmakers comes down to: "full overlay" is a frameless term, and face-frame shops apply it by their own house rule. Some mean a 1-1/4 inch overlay on a 1-1/2 inch stile, leaving a 1/4 inch reveal. Others mean whatever produces a 1/4 inch gap between doors. Neither is wrong; they are different house rules, and neither is your house rule.
So the number to ask for is never the adjective. Ask for these three:
| Ask for | Typical answer | Why |
|---|---|---|
| Stile and rail width | 1-1/2 in (38 mm) | The whole overlay budget comes out of this |
| Overlay per edge | 1/2 in, 5/8 in, 1-1/4 in, 1-3/8 in | Fixes door size directly |
| Gap between adjacent doors | 1/4 in or 1/2 in | Tells you whether the overlay is symmetric |
Door width for a single door with a 1/2 inch overlay on a 21 inch opening: 21 + 1 = 22 inches. Change the overlay to 1-1/4 inch and it becomes 23-1/2 inches on the same cabinet. That is a 1-1/2 inch swing from one field on a spec sheet.
Scenario C: Inset Doors
Inset removes the ambiguity about overlay and replaces it with an unforgiving tolerance. The door has to fit inside the opening with an even gap on all four sides — 3/32 inch (about 2.4 mm) is a common target, and 1/8 inch (3 mm) is the loosest that still looks intentional.
What changes for the factory:
- Opening squareness now matters as much as door size. An opening 2 mm out of square shows as a wedge-shaped gap.
- Wood movement is no longer absorbed by an overlay. A solid-timber inset door for a humid destination market needs a seasonal allowance the buyer must agree in writing.
- The hinge is a different part number, not a different setting.
If the buyer is ordering inset for a market with a large humidity swing, that assumption belongs in the order confirmation alongside the moisture content, the same way it does for wood moisture content for export furniture.
Scenario D: A Pair of Doors on One Opening
The centre gap is the number most orders omit, and it is the one the customer sees first because it runs at eye level down the middle of the cabinet.
For a pair, each door = (opening + 2 × overlay − centre gap) ÷ 2.
Worked on a 30 inch face-frame cabinet with 1-1/2 inch stiles (27 inch opening), 1/2 inch overlay, 1/8 inch centre gap: each door = (27 + 1 − 0.125) ÷ 2 = 13-15/16 inches. Omit the centre gap from the calculation and both doors come out 1/16 inch wide, they bind, and the whole batch gets planed by hand on arrival.
The Hinge Has to Agree With the Number
Overlay is not only a door dimension. It is set by a system: the cup, its distance from the door edge, the arm crank and the mounting plate height. Nearly all concealed hinges use a 35 mm cup, which is why "35 mm hinge" is not a useful spec on its own — full overlay, half overlay and inset versions all share it.
In Blum's CLIP top system, taken as one published example, mounting plate spacing runs 0, 3, 6 and 9 mm, and the relationship it publishes is KT = FA + 3.5 mm + MD, where FA is the front overlay and MD the plate spacing. The consequence for an order: swapping a 0 mm plate for a 3 mm plate moves the overlay by 3 mm without any change to the door. If your buyer supplies the hinges and you supply the doors, one of you is going to be 3 mm out unless the plate height is on the packing list.
Decision Matrix
| The buyer wrote | Do not assume | Ask this | Then cut |
|---|---|---|---|
| "Full overlay" | That the door covers everything | Frame or frameless? Stile width? Overlay per edge? | Face frame: opening + 2 × overlay. Frameless: box − reveal |
| "Half overlay" | That it means half of full | Is there a shared centre partition? Thickness? | Partition ÷ 2 per door, minus the gap |
| "Standard overlay" | Anything at all | Which number is standard in your programme? | Only after the number arrives |
| "1/2 inch overlay" | That the frame is 1-1/2 in | Stile width and the gap between doors | opening + 1 in, checked against the reveal |
| "Inset" | That an overlay hinge will do | Clearance target and squareness tolerance | opening − 2 × clearance, all four sides |
| "European style" | Frameless automatically | Frameless carcass, or face frame with Euro hinges? | Confirm before quoting |
Next Steps
Three things close this gap permanently, in order of how much rework they prevent:
- Put the overlay convention in the order confirmation, not the drawing notes. One line — "Face frame, 1-1/2 in stiles, 1-1/4 in overlay per edge, 1/4 in reveal, 1/8 in centre gap" — makes the door width arithmetic reproducible by anyone who reads it.
- Publish a labelled overlay diagram with the product, not just a dimension list. The buyer confusion here is spatial, and it does not survive a table of numbers. What ends it is a cross-section image with the frame width, the overlay and the reveal each marked against the actual geometry: the numbers pinned to the real edges they describe, exported at the size the buyer's platform or catalogue expects. That is a measuring job rather than a photo-editing one, and it is a very different thing from an image generator, which will letter a plausible "1-1/4 in" onto a cabinet it never measured. On a joint where a 3 mm error is a rejected container, a plausible number is worse than no number. Reference figures for the carcass sizes those doors sit on are on the standard kitchen cabinet dimensions page, and a worked before/after on a cabinet listing is in this wall cabinet size label case study.
- Ship the hinge spec with the door spec. Cup diameter, drilling distance, crank type and plate height. If those four are not agreed, the overlay you cut is a proposal.
Wholesale buyers ask for these numbers earlier than retail buyers do, and in a fixed order — the same order set out in standard cabinet dimensions wholesale buyers ask for. The internal figures that go with them are covered in wardrobe internal dimensions.
FAQ
What is the difference between full overlay and half overlay?
Full overlay means one door covers the full width of the cabinet edge or frame edge available to it. Half overlay means two doors share one partition or stile and each covers about half of it. Half overlay is defined by the sharing, not by being half the size of a full overlay.
Is full overlay the same on face frame and frameless cabinets?
No. On a frameless cabinet a full overlay door covers the box edge, leaving only a reveal of about 3 mm. On a North American face-frame cabinet, "full overlay" conventionally means a 1-1/4 inch overlay on a 1-1/2 inch stile, which still leaves a 1/4 inch reveal. The same phrase produces different door widths on the same cabinet size.
How do I calculate cabinet door size from the overlay?
For a single door on a face-frame opening: door = opening + 2 × overlay. For a pair: door = (opening + 2 × overlay − centre gap) ÷ 2. For inset: door = opening − 2 × clearance, typically 3/32 inch per side. For frameless full overlay: door = box face width minus the reveal allowance.
What is a standard cabinet door reveal?
On frameless cabinets, 1/8 inch (about 3 mm) between doors is the common default, with 2 mm used for tighter programmes. On face-frame cabinets with a 1-1/4 inch overlay and a 1-1/2 inch stile, the reveal is 1/4 inch per edge.
Do all concealed hinges use a 35 mm cup?
Nearly all European-style concealed hinges do, across full overlay, half overlay and inset versions. Because the cup is shared, "35 mm hinge" does not tell you the overlay. The overlay comes from the arm crank and the mounting plate height, so those have to be specified separately.
Sources & References
- CabinetSense Wiki — Reveals: overlay as a face-frame term, reveal as a frameless term
- WoodWeb Knowledge Base — Defining "Full Overlay" on Face-Frame cabinets (professional disagreement, stile widths, gaps)
- Showplace Cabinetry — What does overlay mean: full, partial, frameless and inset (3/32 in inset clearance)
- Blum catalogue and technical manual — CLIP top mounting plate spacing, overlay relationship, glass door gap recommendation
- Eagle Woodworking — Framed vs frameless cabinets: door installation requirements