We moved to a cottage last May so have been living here for about a year. The bathroom is downstairs next to the kitchen which is quite small. bathroom and kitchen is an existing single storey extension to the rear of the cottage. We are thinking of having an extension - which will probably mean knocking down replacing the existing kitchen and bathroom with a larger kitchen and utility room (total about 30 square metres)above this on the second floor a new bathroom (say 16 square metres). I realise that this gives little detail but does anyone have any idea of the cost of such an extension which would a rendered finish (so breeze block construction?)compared with say an oak framed extension? Thank you.