We bought a new house in AZ 18 months ago from a large builder. We complained about the summer electric bills being too high ($550) and were told numerous times they were normal. Finally, a customer service rep cut into the drywall ceiling to gain access into that section of the attic and found there was no insulation. They are going to add blown insulation tomorrow taking it to R44 and topping off the rest of the house that is currently R38 to R44 in order to recoup the money we spent on our bills. That is all the restution they are willing to give, stating they have the right to repair. Any professional advice would be greatly appreciated. Also, does the restitution sound fair to you professionals? I know the FTC 460 says we're protected, but that doesn't help us now. Thank you for any input you can give!

How is the adding insulation going to recoup your bills? Sure it will save you money on future heating/cooling costs. But not going to pay you back for the money you already spent.

They do have the right to repair under the warranty. But I would not sign off on the repairs until you speak to a lawyer that represents you. The Warranty company and the customer service rep does not work for you. Once you sign off on the repairs, your stuck with any results good or bad.

Every state has its own laws regarding warranty repairs. Some better then others. You need to research this. Also check with local building office. Perhaps they need to pull permits to do this job? As they are modifying the existing so called approved job that they did before you purchased the home. It sounds like someone did not do something correctly while the home was being built.
I would also get a home inspection performed. This person although a generalist will help you develop a list of issues that you may not know exists with the home. Some of which will rear its ugly head long after any warranty is over.
I am sure the real estate agent and the builder said you do not need this prior to taking ownership as the house is under warranty. Oftentimes more then not we find real issues with new construction that is over looked by the construction inspectors and end up being major issues with the house later on.

I very much appreciate your reply and advice; I will do as you suggested, with the exception of contacting a lawyer. I don't want to incur more costs. We did have a home inspector at the one year mark; but since there was no access to that part of the attic, it wasn't checked. We needed 3 pallets of roof tiles to replace the broken ones. Again, I really appreciate your input, thank you very much for pointing me in a direction and validating my concerns.