2d house extension plan to 3d (exterior)

need 2d plan of house extension turning in to 3d plan...we are having frontal extension to house. we have had plans drawn up but they do not offer a very good idea of what the extension will look like . extension is joining house with garage (but garage is on an angle) ..we have plan showing actual house - then plan with proposed extension. We want a visual of what a pitched roof would look like and what the proposed apex roof extension would look like. not to bothered with the internal stuff (its more about the exterior visual.