National Building code is a document containing standardized requirement for the design & construction of most types of apartments in India.
The NBC 2005, formulated by the Bureau of Indian Standards, spells out new regulations for adoption by infrastructure departments, municipal administrators, public bodies and private agencies. It contains mainly administrative regulations, development control rules and general building requirements, fire safety requirements, stipulations on use of materials, structural design and construction and building and construction, building and plumbing services.
All materials and workmanship shall be of good quality conforming generally to accepted standards of Bureau of Indian Standard specification & codes as included in National Building Code of India. No building or part of a building shall be constructed or reconstructed or no addition or alteration shall be made to any existing building in the intervening spaces between the building and any overhead electric supply line.
Every person who intends to erect, re-erect or make alternation in any place in a building or demolish any building shall give notice in writing to the concerned Authority of his intention in the prescribed form and such notice shall be accompanied by plans and statements in sufficient copies.
No Objection Certificate (NOC) from the Fire Service, Pollution Control Board, Electrical safety department, Water Supply and Sewage Department and other concerned a department.
Deviation from approved plan or violation of National Building Code (NBC) will lead to charge penalty, cancellation of approvals or demolition of property.
Now you have to analyse how much this deviation caused.