Deltana DDQ56 Dutch Door Quadrant, Solid Brass

Two different mechanisms for the same goal. The quadrant, like the Deltana DDQ56, is a pivoting arm that swings across the joint between the two leaves and sits proud on the face of the door, so it can be thrown or released without much precision in the alignment. A Dutch door bolt such as the Emtek 8516, a 4 inch bolt, is a sliding bolt that shoots into a strike or keeper on the opposing leaf, which means the two halves need to line up closely for it to engage. On an old door that has settled or a wide leaf that sags a little, the quadrant is the more forgiving of the two.

It only joins the two leaves to each other. The quadrant is not a security device and does not latch the door to the jamb, so you still need a latch or lockset on the door itself. On a Dutch door the normal build is a lockset in the lower leaf plus the quadrant tying the upper leaf down, so throwing the quadrant lets the whole door operate off the one lockset.

Emtek's dutch door hardware is the 8516 Dutch Door Bolt, a 4 inch bolt. Both join the upper and lower panels of a dutch door so the two halves operate as one leaf, but they work differently: the Deltana DDQ56 is a quadrant, a solid brass arm that pivots across the seam between the panels and is surface mounted on the face of the door, while the Emtek 8516 is a bolt that throws 4 inches to tie the panels. If the door face is already prepped for a quadrant arm, the DDQ56 is the like-for-like part.

Solid brass, both the material and the substrate. That matters on an exterior Dutch door where a plated steel part would rust at the fastener holes and at the pivot. Brass also means the piece can be refinished if it gets scuffed on a rental turnover.

Nine finishes: polished brass, antique brass, PVD polished brass, oil rubbed bronze, brushed nickel, antique nickel, polished chrome, brushed chrome, and paint black. If you are matching a fleet of doors across a building, the PVD polished brass is the one to specify where the quadrant sees weather or heavy hand contact, since PVD is a deposited coating rather than a lacquer.

One per door. The DDQ56 is sold each, and a single quadrant on the lock stile is the normal arrangement for tying the two leaves together. If you are hardware-ing out a building with, say, twelve Dutch doors, that is twelve pieces, and each finish is ordered separately.

Usually yes, but plan on new holes. A quadrant like the DDQ56 mounts on the face of the two leaves and pivots, while a sliding bolt such as the Emtek 8516 mounts along the stile and needs a keeper on the opposite leaf. The footprints are not the same, so the old fastener pattern and the old keeper mortise will not be reused, and on a painted or stained door you may see witness marks from the previous part. Swapping the other direction has the same issue.

They solve the same problem with different hardware. A quadrant like the Deltana DDQ56 is a pivoting solid brass arm mounted on the face of the door; you swing it across the joint to lock the top and bottom panels together and swing it clear to work the halves independently. A dutch door bolt like the Emtek 8516, a 4 inch bolt, slides rather than pivots. Pick by what the door is already prepped for and by how much face hardware you want showing on the panel.

The Deltana DDQ56 quadrant is the finish-driven choice: it comes in oil rubbed bronze, brushed nickel, antique nickel, paint black, polished chrome, brushed chrome, polished brass, antique brass and PVD polished brass, so it can be matched to the knobs, hinges and other trim already on the door. The Emtek 8516 dutch door bolt is the alternate part for the same function. For a property manager standardizing a set of dutch doors across a building, the nine finish options on the solid brass DDQ56 are what let one part number carry every opening.

Commercial. It is carried as commercial door hardware, which is the relevant answer for a property manager or an institutional buyer specifying Dutch doors in a nurse station, a daycare pass-through, or a service counter, not just a residential kitchen door.