Timber alone isn't enough at large sizes. Doors past 2340 × 920mm — and any door with a chevron or herringbone pattern — need internal steel reinforcement to hold straight over time. That's what EverFrame™ is.
When you commission a custom door, you'll spend a long time choosing the timber, the pattern, the size, the proportions. You won't spend much time thinking about what's inside the door. Most people don't. Most door manufacturers don't either, which is part of the problem.
What's inside an external door — between the two faces — is the difference between a door that holds straight for thirty years and a door that twists out of shape inside three. Solid timber is a beautiful material, and at standard residential sizes (2040 × 820mm) a well-built timber slab will perform fine without any special treatment inside. But timber moves. It expands and contracts with humidity. It creeps along the grain. It responds to gravity, particularly when you're hanging or pivoting it on a single point. At standard size, this movement is small enough that the door tolerates it. At large sizes, the same movement becomes structural.
The threshold is roughly 2340mm tall and 900mm wide. Past that, you're asking timber to span more than its natural stiffness can hold. The door will sit on the hinges fine. It'll close fine. Then over a year or two, the bottom corner — the one furthest from the hinges or the pivot pin — will start to drop. The gap at the bottom of the door grows. The door starts dragging on the threshold. The seals fail. You can plane and shim your way out of it for a while, but the door is fighting itself.
Pattern doors fail the same way, smaller. An EMBER chevron door has lining boards laid in opposing angles. Beautiful when it's just been made. Structurally, those opposing angles create lateral forces — the timber wants to expand along the grain in two directions at once, and where the angles meet, the door wants to fold or buckle. Same with BONE's herringbone pattern, just at smaller increments. Without internal reinforcement, those patterns drift and creep over time, and the geometry that made the door beautiful becomes the thing that pulls it out of shape.
EverFrame™ is the answer. It's an internal steel reinforcement system built into the core of the door at manufacture. Not bolted on, not screwed in — built into the door's structural makeup so that the steel becomes part of the door rather than something attached to it. The steel takes the lateral and torsional forces. The timber takes the visual and tactile job it's good at. The two work together rather than against each other.
EverFrame is included as standard on EMBER and BONE, because the patterns require it. It's also included on any door past the 2340 × 920mm threshold, because the size requires it. On a standard NORTH at standard size, EverFrame isn't included because the door doesn't need it — but it's available as a no-fuss upgrade if you want extra structural insurance.
Every EverFrame door is backed by a 10-year structural guarantee. If a door we built with EverFrame steel reinforcement twists, drops, or warps inside that window, we replace it. Not patch, replace. We've never had to invoke it because we engineered the system to work, but the guarantee is in writing because we want you to take the door home knowing it'll still be straight in ten years.
What's inside the door matters. It's the part you can't see, but it's the part that decides whether the door you bought is the door you'll still have in fifteen years.