What is substructure and superstructure in building?

The two major components of buildings are the substructure and superstructure.  The substructure is the part of the building that is underneath the ground, while the superstructure is everything that is above ground.

Substructure

The purpose of the substructure of a building is to transfer loads of the superstructure to the soil that is underneath.  This is why the substructure is right against the soil that supports it.  Now, it is important that you spend time working with structural engineers to ensure that all support beams, columns, and foundations are incorporated properly to ensure that nothing will collapse within the substructure.

Most of the time, the substructure is made from plain cement concrete or reinforced cement concrete.  Once that is in place, stones, bricks, or additional concrete is added until it all reaches the plinth level.  It is necessary for a damp-proof course to be laid on top, so that moisture doesn’t penetrate any part of the substructure.

Superstructure

The superstructure of a building is where people will spend most of their time.  This area includes the first and second floors inside a home and any number of floors in larger buildings.  The superstructure includes beams, columns, finishes, windows, doors, the roof, floors, and anything else.

The parts of the superstructure are much lengthier than the parts of the substructure.  This shouldn’t be surprising since the superstructure is much larger than the substructure.

Parts of the Superstructure

The Floor

The floors of the superstructure are what separates the different levels of a building.  Of course, it is also the area where you walk around, place furniture on, and store numerous items.

The Roof

A roof is necessary on every building because it keeps the floors, and the rest of the superstructure, out of the elements.  There is not a one roof fits all solution when it comes to roofing options, so depending on where you are constructing a building, you can choose from different types of roofs.  Flat roofs are often used within the plains, while sloped roofs are best near the mountains or where there is a lot of snow.

The Lintel

The lintel is the area over any doors and windows, and it is there to support the wall over the larger openings.  A lintel beam is normally made from reinforced cement concrete, but it can also be made from concrete and bricks.  The width of the lintel is usually the same as the width of the wall.  When it comes to the thickness though, the lintel should never be thinner than four and a half inches.  However, it should also never be thicker than its width.

The Parapet

The external walls that extend past the roof slab are called parapets.  The purpose of this part of the superstructure is to keep water from pouring over to the entrance of the building, while also offering a safe spot for those who are up on the roof.

The Sun Shade

The sunshade is put in place with the lintel and it protects both doors and windows from the sun and the rain.

The Beams

Beams are horizontal elements that withstand all vertical loads.  All the weight from those vertical loads are supported at the endpoints of the beams and that weight is then transferred to the columns or the beam supports.

The Columns

Columns are vertical structures that can hold a lot of weight.  Any columns that are not put in place properly will collapse once additional weight is put on top of them.  Of course, all that weight goes from the columns down to the foundation.

The Walls

Without walls inside a building or a home, we would all have large wide-open spaces.  However, since none of us wants our bedroom right next to the kitchen, walls are always installed to enclose specific areas of buildings.  Most walls are made from concrete or masonry and they hold the weight from the roof, slabs, and even the beams.

The Doors, Windows, and Other Openings

All the doors, windows, and other openings in a house or building are also considered part of the superstructure.  The number of doors, windows, and other openings will be dependent on how large the building or house is.

Stairs, Ramps, Lifts, and Other Vertical Transportation Structures

All those vertical transportation structures that you see in buildings and homes are part of the superstructure.  While stairs and ramps are often the only things seen in homes, buildings will also usually have escalators and elevators.

All the Finishing Touches

Most people forget that all the finishing touches inside a building or a home are part of the superstructure.  This includes trim, flooring materials, curtains, blinds, and even heating and cooling units.

Differences Between the Substructure and Superstructure of a Building

You can probably see the difference between the substructure and superstructure of buildings now, but to make sure, we have created a handy recap below.

Substructure

• The structure that is below the damp proof course that includes the ground floor and foundation
• The structure that is below the plinth
• This structure transfers the loads that are received from the superstructure and transfers it to the foundation
• Includes the foundation, pier, and abutment

Superstructure

• The internal and external elements of a building that is over the substructure
• The structure from the top of the plinth to the top of the building
• This structure transfers the loads from the upper part of the building to the substructure
• The structures above the baring and the wearing surface
• Includes walls, beams, columns, windows, doors

As you can see, both the substructure and the superstructure are important parts of buildings and you cannot successfully have a building, or a home, without both of them in place.  If you try to build just a superstructure without a substructure underneath, the entire superstructure will eventually collapse under the weight of the very top.

Therefore, make sure that your substructure is always very stable before you add an even sturdier superstructure on top.  That is the only way that you will have a home, or a building, withstand the elements and everything else that Mother Nature and humans bring their way.