timber frame specification + Minor amendment to existing outline planning consent

We have architects drawings and specs for a traditional build single story residential kitchen extension; however we have decided to go for a timber frame construction and so need specs for it. To keep the cost within budget we need it to be as simple as possible to be "signed off". As you may see on the drawing we have simplified the roof by making it all flat and reducing the skylights. We have dug the foundation and will concrete it next week subject to the building inspector being happy with the trench. We will also complete the rain, soil and sink waste drainage in accordance with the current specification on the drawings. We also want to put a wooden suspended joist flooring rather than a solid floor. The project is highly cost sensitive so we will be driven by the lowest cost minimalistic, no frills options and the cheapest materials. We intend to use the same steel frame goal posts as in the current spec. The project is an extension to the rear of a terrace house in Norwich. The specification document is similar to the one i posted, which is for building with bricks and blocks; so it needs changing to one for a timber frame build showing the materials and that they meet UK building regulations. so the document can be produced anywhere in the world as long as it is for UK regulations. An experienced timber frame architect should be able to cut and paste from a previous one he has done before.