Website refresh

I require a new fresh look for a site which has not changed for 7 years. The database interation & server side programming will be done by us so this job is just to redesign the front page with a fresh new look which we can then replicate across the site.
To recap, I require a one page template (created from scratch rather than a third party template). The new design must be CSS driven & cross browser friendly (inc mobile devices). The site is used regularly by a loyal customer base so the new design should not be too radically different from the existing site. The new logo must feature & the look should be clean, simple & fresh.