Recently asked to give some broad guidance on maximum allowable door sizes using the Geze TS500 NV floor spring for a set of double timber doors (44mm thick solid core) 1050mm wide, an opening height of 3.2m, where the door height could be maximised without an obtrusive overpanel. Was there a weight rule of thumb for timber doors that could be applied to determine how high to safely go, and are there any other considerations of stability that need be considered? With reference to Geze’s technical pdf, and working on the approximate weight of 120kg per leaf, which we estimated from the dimensions & description, then the TS500 NV would just about do it. However we recommended going for the new TS550 NV floor spring as the door size & weight falls more easily into it’s comfort zone, it will give a longer life expectancy as it is not anywhere near it’s maximum capacity. The TS550 NV uses the same strap & pivots as the TS500 NV.