Why wouldn't you? You've bought a new house. It's everything you wanted and the contractor was great to work with. When you had concerns, he listened. When he bought the wrong paint, he immediately replaced it. He even bought you a local wine to celebrate the completion of the house. You couldn't be happier.
Except--except that 6 months after moving in you find the roof is leaking due to an installation problem, and both your roof and your contractor have left you out in the rain. So why wouldn't you just call him, write him, stop by his office? After all, during construction he was there faster you could pour a glass of Shiraz. Why wouldn't he still be concerned with getting it right?
Being your own advocate can cost you money
It's natural to want to try and work with someone when there is a problem--especially with someone who has been reasonable in the past. Attorneys seem like they can cost a lot and why not save money where you can after you just invested a bundle in your dream house? But thinking like an attorney is probably not what you do best.
You've heard the phrase, "Everything you say can be against you in court." We usually associate this statement with criminal cases. But it is just as important in a situation that has the potential to end up in civil court. If you don't keep accurate records of phone calls, letters, and emails, it's his word against yours and that could be the just the thing that brings your rooftop--and your case-- tumbling down.
Leave it to an expert
You wouldn't try to build that dream house on your own, so why take a chance and try to arbitrate on your own? Bringing in a neutral party who has your best interest at heart is the safest thing you can do--and the most expeditious.
The farther you get from finished construction, the easier it is to blame the homeowner for the problem--the contractor's attorney will ask: Did you walk on the roof, did you try to fix it yourself? If you did, he may argue that you created the problem, not his client. In the end you could spend more time and money than you ever expected.
Leaving legal issues to legal professionals is just plain prudent. In the end, your problem is resolved faster and cheaper--leaving you time to enjoy your new home, and that good bottle of wine.