Overstepping from my husband

Yesterday,Feb 15 2010. We talked about the eaves of roof of my dormitory when I took him to the bus station. I told the building contractor I did not want any eaves for the roof of motorcycle parking. When my husband saw it, he told me that it should have the eaves. I ignored him. But he told me that he would pay for the eaves, I'm OK. But yesterday he told me that he will shared the half of cost. I don't want it. He said that if I don't pay for it, he will not shared Aomboon's fee of school that I had already paid. I don't care if he don't pay I can pay only. But this is the evidence to get divorce and I will have custody of my children when we get divorce. I call him tell him this but he hung up his phone immediately.