Large garden flat rework drawings

We are in Willesden Green, NW2, and need onsite design - we have a kitchen, utility room, bedroom and 'library' to be drawn for our builder (and I can't believe how difficult it is to find someone!). Attached a floorplan - we are ditching the kitchen and starting from scratch with underfloor heating, replacing the adjoining shower room as a utility room, and building an ensuite into a bedroom to replace the lost shower. We are also converting one of the sitting rooms into a library, as per the attached photo. We have a carpenter who will do / supervise the works etc, but he/we need drawings and inspiration.

Could you help?

Doug & Tilly Brodie
St Gabriels Road, NW2 4ds