This joinery has been detailed for an Architect’s own home where we were instructed to ” Make it beautiful ” His original Shugg concept was altered to introduce Rosewood and Western Red Cedar DG double hung window design, similar to NZS 4211 with a variation of using a Rosewood beveled timber interlocker , and the use of S/S chains and exposed S/S weights. For less
maintenance the timber sill is covered in Zinc cladding, This is detailed for Zinc ”Z” upstand to be set up inside a rebated bottom rail of the fixed bottom sash and up under exterior
reveals and facings, and completely capping the sill. Galv 30 x 8 mm flat bar is laminated, on the flat, with in the center rails.

For the operation of the heavy double glazed sash it required a lot of detailed drawings for manufacture of many bespoke items, so some became a feature of the job.   Some items are unseen like a special pin link clip for the chain to screw attach to the sash and a small chain axle pin with circlip for joining clip to the chain, which meshes over a tooth sprocket that has been designed with a plastic bearing for longevity. The sprocket axle is featured with no visible means of attachment to the frame. This was accomplished by manufacturing an axle with a slot for a hidden key way to slide up through this slot and screwed either side of the axle into the jamb to secure all. A cover plate hides all. The chain ends at a featured polished S/S tube counter weight where attachment to this made to 75mm diameter capped S/S tube, filled with lead shot through an unseen small hole in the rear of the tube for a counterweight. This weight is guided up and down by a plastic guide block attached to the top of the tube running in a full height vertical plastic channel housed flush into the back of the Rosewood jamb of the joinery.
As Rosewood is purchased at 50mm thick in wider boards, all the frame joinery was laminated thicker with mitered joints so glue lines were on the edges of the timber, giving the appearance of having been made from larger dimensioned timber.