Usually Basement construction is not approved for individual residential units or houses. In most of the states- the regulations require at least 102 feet of construction above ground level to allow for 17 feet of construction below ground level. This means you will need 6 storeys above the ground level [In some states the numbers are 85:17 or 68:17 but rarely does the ratio go below 4:1]
So as long as you follow this rule - you can build any basement. Otherwise regulations will not permit it and if discovered (in 10% cases) - corporation will impose fines or other forms of demolition exercises.
According to the National Building Code regulations or building by-laws, a basement can be used only for the purpose of storage, dark room, bank cellar, or parking space. Kitchens, bathrooms and toilets are also not allowed in a basement, unless the sewer levels permit the same.
NBC guidelines related to basements
- The minimum height of the basement should be 2.5 metres and the maximum height 4.5 metres.
- The ceiling height should be a minimum of 0.9 metres and maximum of 1.2 metres above the road surface.
- Ventilation is must for the basement and could be in the form of blowers, exhaust fans, air-conditioning, etc.
- Surface drainage should not enter the basement.
- The basement’s walls and floors must be water-proof.
- The basement should not be accessed directly from the road. It should be accessed only from the main entrance or an alternative staircase that provides access to the building.
- Only when a projecting basement is flush with the ground, or if the authority allows, can the basement be permitted to touch the adjacent property.
And as per 4.5.5 chapter 4 of Model Building Bye Laws - Ministry of Housing and Urban Affairs
The construction of the basement shall be allowed by Authority in accordance with the land use and other provisions specified under the Master Plan/Zonal Plan. The basement shall have the following requirement:
i) Every basement shall be in every part at least 2.5 m. in height from the floor to underside of the roof slab or ceiling and with maximum height not more than 4.5 m.
ii) Adequate ventilation shall be provided for the basement. The standard of ventilation shall be the same as required by the particular occupancy according to Building Bye-Laws. Any deficiency may be met by providing adequate mechanical ventilation in the form blowers, exhaust fans (one exhaust fan for 50 sq m. basement area), air-conditioning system, etc.
iii) The minimum height of the ceiling of any basement shall be 0.9 m. and maximum of 1.2 mt. above the average road level on the front side of the building.
iv) Adequate arrangement shall be made such that surface drainage does not enter the basement.
v) The walls and floors of the basement shall be watertight and be so designed that the effect of the surrounding soil and moisture, if any, are taken into account in design and adequate damp proofing treatment is given.
vi) The access to the basement shall be either from the main or alternate staircase providing access to the building. No direct entry from the road shall be permitted to the basement.
vii) Basement in an individual plot touching the adjacent property shall be allowed subject to following:
a) In all cases the owners shall have to indemnify the local body against any damage caused by her/him/them to the adjacent property (Appendix-B-1).
b) In case the portion of the basement projecting out of the building line that shall flush with the ground.
viii) In case partition in the basements are allowed by the Authority, no compartment shall be less than 50.0 sq m. in area and each compartment shall have ventilation standards as laid down in sub-clause (ii), above separately and independently. The basement partition shall however, confirm to the norms laid down by Fire Services.