Retrofitting Cabinet Hardware: Old Holes, Backplates, Re-Drilling

Short answer

Existing doors and drawers already carry holes, and new hardware almost never matches them. Three real routes exist. Match the existing center-to-center (CTC) exactly and the new pulls bolt straight on — free, but it limits selection. Use a backplate sized to cover the old spread, hiding the holes without touching the door. Or fill and re-drill, which opens the whole catalog but repairs invisibly only on painted and, with care, stained wood — thermofoil and laminate cannot be patched convincingly. Measure your existing CTC first, hole center to hole center, in millimeters. That one number decides which routes are available.

The retrofit problem, stated plainly

A hardware-only refresh is the highest-return cosmetic change available on a kitchen — a fraction of the cost of new doors, and it changes how the room reads. The obstacle is the boring pattern the old hardware left behind: modern hardware sells on a metric ladder, while older North American cabinetry was drilled on an imperial one. A kitchen drilled at 3" CTC in 1998 will not take 96mm pulls without a 0.75mm fight or new holes.

Before choosing a route, inventory the kitchen: for every door and drawer, record the number of holes, the CTC if there are two, and the door construction. You will often find more than one pattern — drawers at one spacing, a pantry at another, a few doors replaced along the way. Each pattern is a separate decision.

Measuring an existing CTC accurately

Measure with the hardware removed, from the center of one hole to the center of the other. Three ways to get it right: center to center with a rule; left edge to left edge, which gives the same number because the holes are equal diameter; or outside spread minus one hole diameter. Never measure an installed pull — that reads overall length, not the mounting dimension.

Work in millimeters. The gap between 96mm and 3¾" (95.25mm) is invisible in fractional inches and obvious in millimeters, and 0.75mm is enough to stop two screws starting. Holes at 128mm will fight a 5" pull (127mm); holes at 76mm take a 3" pull without complaint.

The four routes, compared

The basis of comparison below is what each route costs in selection, labor, and finish risk — not which gives the best result, since that depends on how your doors are built.

Backplates: the underrated route

A backplate sits between the pull or knob and the door. It began as a wear plate; in a retrofit it is a cover. Size it by measuring the full spread of the existing holes — outer edge to outer edge — and picking a plate that exceeds that in both directions with margin, so no old hole peeks out under raking light.

Two notes. Many backplates are pre-drilled for a specific CTC, so the plate must match the new pull as well as cover the old holes; some ship undrilled for that reason. And a backplate changes the fastener math — budget a screw about a quarter-inch longer, ordered from the fasteners catalog.

Filling and re-drilling, by door construction

The repair depends entirely on what the door is made of, and this is where most retrofits go wrong.

• Painted doors — the best case. Two-part filler or hard wood filler, sanded flush, primed, and touched up with the original paint gives a genuinely invisible repair. The risk is sheen, not color: a spot repair in the middle of a satin door often flashes. On a flat door face, refinishing the whole face beats three touch-ups.
• Stained solid wood — workable with care. Plug with a dowel of the same species, grain aligned, glued and sanded flush, then stain and topcoat to match. Expect the plug to take stain differently because end grain absorbs more — test on a scrap. Good at normal viewing distance, rarely perfect up close.
• Thermofoil and laminate — the hard case, and the honest answer is usually no. Thermofoil is a vinyl film heat-formed over MDF; laminate is a printed sheet. Filler bonds to neither, and the printed pattern cannot be reproduced. Match the CTC or use a backplate. If neither works, new doors are the realistic path — compare options in the kitchen cabinets catalog before spending labor on a repair that will show.

Converting knobs to pulls

Going from one hole to two is the most common retrofit request, and the trick everyone reaches for — reusing the existing hole as one of the two — works in some places and not others.

It works well on doors, where a knob normally sits near a corner on the stile: use that hole as the lower hole of a vertical pull and drill one new hole above it at your chosen CTC. Only one hole is new, and the pull lands correctly positioned. It also works on wide drawers with two knobs at the quarter points — measure the spread, and if it lands on a stock CTC, often 160mm or larger, a single long pull may bolt straight on with no drilling.

It does not work on a single centered drawer knob: using that hole as one of two puts the pull off-center by half the CTC, which reads as an error on every drawer in the run. There the choice is a backplate, or fill and re-drill.

Drilling: jigs, direction, and blowout

A drilling jig is not optional across a whole kitchen. Hand-marking twenty-five drawer fronts gives twenty-five slightly different results, and the eye reads a drawer run as one line. A jig with adjustable CTC stops and edge references — True Position, Kreg, and Rockler all make one — repeats the pattern identically on the second, tenth, and twenty-fifth piece.

Drill from the face — that is the surface that must be clean — and control the exit, not the entry. Clamp a sacrificial backer tight against the back so the bit passes into wood instead of breaking into air, and use a sharp brad-point bit at moderate speed. On thermofoil the blowout risk is highest: tape the drill point, run slower, let the bit cut. Work on a bench, door off.

For homeowners refreshing one kitchen

Measure one drawer and one door in millimeters with the hardware off. Then test on the least visible door in the kitchen — inside a pantry, or beside the refrigerator — before touching anything you look at daily. Buy one pull and fit it. If your route involves filling, do one hole and let it cure and finish fully first; the sheen tells you within a day whether the repair will disappear. If you are keeping some doors while changing others, our guide to matching discontinued cabinets, doors, pulls, and finishes covers working from the physical part when the model number is gone.

For contractors quoting a hardware refresh

Survey before you quote. Count doors and drawers, record every distinct CTC, and note door construction per elevation. A hardware swap and a fill-and-refinish job are different trades with different numbers, and the difference is often thermofoil hiding behind what looks like painted wood.

Price per opening, not per kitchen. Direct-swap, backplate, and fill-and-redrill openings each carry their own labor. Quote them as separate line quantities so a change in the mix does not eat the margin.

Warn the client in writing. Filled holes on stained wood show under close inspection, spot paint repairs can flash in raking light, and thermofoil cannot be repaired at all. Acknowledgement before the first hole is filled is the difference between a completed job and an argument.

Standardize the target CTC. On a multi-unit refresh, pick one CTC and drive every unit to it. Drilling with one jig setting is far faster than resetting per unit, and it makes spares a stock item.

Order screws and spares as line items. Backplates need longer screws, and fill-and-redrill needs filler and touch-up. Add 5% spare hardware. Treat any published figure as a typical 2026 market range for the category and confirm by quote — a Super Arbor Pro account is the route for quantity pricing across a property.

Frequently asked questions

How do I measure the center-to-center on my existing cabinet pulls?

Remove the pull and measure from the center of one hole to the center of the other, in millimeters. Measuring left edge to left edge gives the same number; measuring an installed pull gives overall length, which is not the mounting dimension.

Can a backplate cover old cabinet hardware holes?

Yes, provided the plate exceeds the full spread of the existing holes in both directions with margin. Check whether it is pre-drilled for a specific CTC, and order screws about a quarter-inch longer for the added thickness.

Can you fill holes in thermofoil cabinet doors?

Not invisibly. Thermofoil is a vinyl film over MDF, and filler will not bond to the film or reproduce the printed surface. Match the existing CTC, use a backplate, or replace the doors.

How do I convert cabinet knobs to pulls?

On doors, reuse the existing knob hole as one of the two and drill a second at your chosen CTC. On a drawer with a single centered knob that trick puts the pull off-center, so use a backplate or fill and re-drill instead.

Do I need a jig to drill cabinet hardware holes?

For more than a couple of pieces, yes. A jig with adjustable CTC stops repeats the pattern on every front, and a run of drawers is judged as one line — small hand-marking errors show immediately.

Your next step

Pull the hardware off one drawer and one door, measure both spacings in millimeters, and note what the doors are made of — that gives you your route. Then match the CTC against the cabinet hardware collection, or, if the doors are the limiting factor, price replacements in the RTA cabinet range before committing labor to a repair.