Designing with wood
There are limits to how far timber frames can be pushed but you can still do pretty amazing things with PH15 like the double curved roof shown here on a new house in east London by Thiss Studio.
All timber frames require racking and one of the most frequent problems we have to overcome is the lack of it. When entire walls are given over to glazing and internal spaces are open plan and vaulted there are often insufficient walls to use for racking to withstand lateral loads. In cases like this the only option is to use steel wind frames which to avoid cold bridges have to be positioned inside the thermal envelope. These steel frames may need to provide racking in two direction and take vertical loads if there are few internal walls. Please consider these factors when beginning the design.
The most straight forward buildings (and therefore the cheapest) will have some uninterupted wall areas, free of openings on all the external walls and some vertical load paths internally that align on all storeys from roof to ground floor that can be racked.
Please checkout the Design Guide for more information about PH15.