Civil engineers involved in building construction should have a thorough understanding of the relevant Indian Standards (IS codes) to ensure compliance with national construction standards. 
Here are some of the main points that civil engineers should be familiar with:

IS 456: Code of Practice for Plain and Reinforced Concrete:

Specifies requirements for the design and construction of reinforced concrete structures.
Covers aspects such as concrete mix design, structural design principles, durability requirements, and construction practices.

IS 875: Code of Practice for Design Loads (Other Than Earthquake) for Buildings and Structures:

Provides guidelines for determining the design loads on various building components, including dead loads, live loads, wind loads, and other relevant forces.
Helps engineers in designing structures that can safely withstand the expected loads.

IS 1893: Criteria for Earthquake Resistant Design of Structures:

Establishes guidelines for the seismic design of buildings and structures.
Defines parameters for assessing the earthquake forces, designing structural elements, and ensuring the overall safety and stability of the structure during seismic events.

IS 800: Code of Practice for General Construction in Steel:

Sets out the requirements for the design, fabrication, and erection of steel structures.
Covers aspects such as material properties, structural design principles, fabrication methods, and quality control measures.

IS 1200: Methods of Measurement of Building and Civil Engineering Works:

Provides standardized methods for measuring various building and civil engineering works, including earthwork, concrete work, masonry, and finishing works.
Helps in quantifying and estimating the quantities of different construction materials and activities.

IS 13920: Ductile Design and Detailing of Reinforced Concrete Structures:

Focuses on the design and detailing of reinforced concrete structures to ensure ductility and resistance against seismic forces.
Provides guidelines for the proper design and detailing of reinforcement to enhance the structural performance during earthquakes.

IS 3370: Code of Practice for Concrete Structures for the Storage of Liquids:

Specifies requirements for the design, construction, and maintenance of concrete structures used for the storage of liquids, such as water tanks or reservoirs.
Covers aspects such as design loads, material properties, and construction practices for liquid-containing structures.

IS 456 and IS 10262: Concrete Mix Design:

IS 456 provides general requirements for concrete mix design, while IS 10262 provides specific guidelines for proportioning concrete mixes.
These codes help engineers in selecting appropriate materials, determining mix proportions, and ensuring the desired strength and durability of the concrete.

IS 383: Specifications for Coarse and Fine Aggregates from Natural Sources for Concrete:

Specifies the quality requirements for aggregates used in concrete construction.
Provides guidelines for the selection and testing of aggregates to ensure their suitability for use in concrete mixes.

IS 800: Code of Practice for Use of Cold-Formed Light Gauge Steel Structural Members in General Building Construction:

Provides guidelines for the design and construction of structures using cold-formed light gauge steel members.
Covers aspects such as material specifications, design principles, connections, and construction practices specific to light gauge steel construction.


These are just a few examples of the key IS codes that civil engineers should be familiar with for building construction. 

However, it is important to note that there are several other IS codes that address specific aspects of construction, materials, and design. Civil engineers should refer to the relevant IS codes specific to their project requirements to ensure compliance with national standards and regulations.