What you are talking about is the statute of frauds. The "real estate" contracts referenced do not include the type of construction work you are talking about. Therefore, the statute of frauds will not bar the claim for extra work in New York. New York does require that all contracts for home improvement be in writing, but the penalty for not having change orders/extras in writing is not prohibition of the claim. Instead, the contractor may be subject to some fines by the NYC Dept. of Consumer Affairs and may not be entitled to contract price but stuck with the" value" of the work.
As a side note, make sure the contractor has a valid NYC home improvement license. If he or she does not, the entire claim is barred.
The information provided herein is for informational purposes only and does not constitute legal advice. No attorney-client relationship is created by this answer. You should consult with a local attorney regarding your specific situation to obtain legal advice.
A contract for construction work is not real estate. If the work was done you owe the money and the contractor can sue you or put a mechanic's lien on your house.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 577-9797 or via email at Eric@RothsteinLawNY.com. I was named to the Super Lawyers list as one of the top attorneys in New York for 2012. No more than 5 percent of the lawyers in the state are selected by Super Lawyers. The above answer is for informational purposes only and not meant as legal advice.