Sq Ft Calculation for Mastry-Urgent!

Hello Experts,

We constructed a house using a (Mastry) contractor only labour contract basis per Sq Ft 180 for Roof area for cement work only.

Its a double storied house and we have first floor staircase outside and on top of that to avoid rain coming into balcony we have put cement slabs by raising the parapet wall 3 ft , which are poured using cement and steel and then plastered it.

And in elevation we have made some groves and additional projection design attaching to roof.

Now the question when we calculate and pay the Mastry or the contractor do we measure only till the Roof length and width leaving any projection which are ornamental in the front side.

As we covered the top of the staircase do we need to measure that also as a separate roof.

Because while calculating our Contractor is putting all these things into Sq ft and also adding the top of the staircase as additional roof which is around 66 SQ FT and also adding the 6 inches length eventhough its only 5 feet in width he is adding it to the total roof area.

So we are confused as this is going over 40 thousand. When we questioned him he said its considered as roof and in the agreement we have mentioned that Elevation is free which is included in the SQ FT 180 only.

Request you all to clarify. As we don't want to cheat him or get cheated

Regards

Neel