I created this website for a guy in exchange of a radon system installed in my house. I designed the site based on his requests, but I feel it could be better.
I agree with your feeling - it could be better IMO the site is too basic... it will do the job but it isn't something that people will remember, it isn't even something that will keep their attention... They'll look at it in spite of the design not because of it... The structure is good - header / contact info, left navigation menu... It just need some beautifying procedures
Suggest moving a little white space from the top of the page to make the design more evenly spaced so the user isnt hit with a massive logo and tiny writing which in the content.
Also ouch, What colors did you use... there is so much white light there my eyes are in pain. Suggest changing the background color a hint.
Logo is too big, make it little smaller, get better fonts.
overall the structure is ok, but menu background and the table sidebar background doesnt make the eye catch feeling.
it is simple, that is great
you are following an easy well recognised design, also good
bad
the logo is blury and thus looks unprofessional
the nav buttons are tiny and may be hard on people who are hard of sight, I am 20/20 and thought they were a tad hard to read
building these things is hard, I have been doing it for the past month or so now and have redisgned my site 3 times, finally feels like it works but who knows..hehe...keep at it
I agree with most of what all above have reviewed from the design point of view but no one has mentioned the content or what the site is for, and I think that you got that right.
IMO the site is too basic... it will do the job but it isn't something that people will remember, it isn't even something that will keep their attention... They'll look at it in spite of the design not because of it... The structure is good - header / contact info, left navigation menu... It just need some beautifying procedures 
