Plan Section Elevation!!!

In every architecture project, you are going to be asked to draw an architectural plan, section and elevation. These drawings are unique to architecture and other design industries and form the foundation of architectural communication.

Plans, sections and elevations are likely unfamiliar to many new students. These drawings may be explained to you in detail or you may be left to figure it out yourself. Either way, there are a lot of things to think about to get started and complete these drawings as a comprehensive and clear method of communicating your design and ideas.

What Is A Plan, Section And Elevation?

Plans, sections and elevations are all scale representations as drawings on a page of much larger, real-life objects or structures. We are shrinking them down.

Learn more in the article titled “How To Use An Architectural  Scale Ruler (Metric).”

Plan, section and elevation drawings are orthographic drawings.

Orthographic projection is a way of representing a three-dimensional form or object in which the object is viewed from a position perpendicular to the drawing plane being viewed.

Learn more in the article titled “An Introduction To Architectural Drawing Systems.”

To keep it simple, let’s consider a capsicum as a three-dimensional object that is hollow inside, like a building or architectural structure.

A capsicum or a house or a box would normally have a top view, a front view and a side view, as well as a back view and a second side view. Some of these views may be similar but unlikely to be the same. The top view is what is called a plan in architecture. The front, back and side views are called elevations.

When we look at them together, these different views give us a full understanding of the total exterior of the object or structure. The only view we are missing is the bottom view.

For a capsicum or a free-standing object, this bottom view is important and completes our understanding of the object. A house or an architectural structure has no bottom view as it is fixed to the ground and we do not get underneath to see it!!

Architectural Plans

Let’s consider plans in a little more detail…

A plan is a view of an object projected horizontally, or from above. In architectural drawing, this is known as a top view, top plan or roof plan.

Our top view of the capsicum is like a roof plan of a building or architectural structure. However, this only gives an understanding of the outside of the three-dimensional form.

Other architectural plans are cut horizontally through the building or object, usually at a height of about 1,000-1,200mm above the ground or a floor plane. These are usually called floor plans and give us information about the thickness of walls and openings as well as the qualities, size and shapes of internal spaces.

A floor plan is like slicing through a capsicum, lifting off the top and then drawing or showing everything you would see – that is both cut through and below the level of the cut.

If we look at what exactly has been cut in the capsicum, we can now see the hollow inside space, as well as the thickness of the skin, how the skin changes in thickness to create interesting internal shapes and spaces, and the fact the skin is solid and there are no  holes or openings (which we would call doors or windows in a building). What is also important is that we can also see the inside skin of the capsicum behind or lower than the level of the cut.

In a building, we slice through at about 1,000-1,200mm above the floor. Let’s say about 1,100mm. The reason we choose this height is that it is about the height where humans use their hands. It is just above benches and tables, and where most windows will run through vertically. This means when we cut through at this height we will capture as much information as possible in our drawings. Consider what you would see if you cut through the plan at 100mm above the floor or 100mm below the ceiling. You would miss all the windows, doors and important elements.

If we look through at exactly what is cut through in a building plan we see wall thicknesses, windows, doors and openings. We can see also see what is below the line of the cut such as any built-in furniture like kitchen benches, sinks, toilets or bathroom vanities. We can also see floor or ground materials and the top of furniture or furniture outlines.

If we put the top of the building back again, what we would see is a top view or roof plan.

Architectural Sections

section is an orthographic projection of an object as if it would appear cut vertically by an intersecting plane.

A section is drawn similar to a floor plan, but vertically. What is most important in a section is the information that is cut through. As a plan, we see wall thicknesses, windows, doors and openings. They must be drawn the same way, as in reality, they are the same thing.

As in a plan, we can also see what is behind the line of the section cut such as any built-in furniture like outlines of kitchen benches, sinks, toilets or bathroom vanities as well as wall materials and objects on walls. This information in the distance behind the cut is internal elevation information.

In a section, the most important information is the cut which communicates the material thicknesses, types, openings and the internal and external spaces, forms and shapes created. The internal elevation information is usually indicative or secondary in a section and is shown in more detail in a drawing dedicated to the internal elevation, which we will get to shortly.

If we have multiple sections cutting through our capsicum or structure, would name each of them with letters – Section A-A, Section B-B etc.

If we put the removed half of the building or capsicum back again, what we would see is an external elevation.

Architectural Elevations

An elevation is a vertical view of an object projected onto a picture plane.

A capsicum has a front, back and two side views or elevations depending on how we position ourselves relating to the object. Similarly, a building or architectural structure will normally have four elevations if it uses square or rectangular geometry. Elevations will be labeled Elevations 1,2,3 and 4, starting at the top and working clockwise. More commonly they will be labeled North, South, East or West Elevation based on the direction the elevation is facing – not the direction you are looking.

A more complex shaped plan with angles or curves may end of with multiple elevations, but that is beyond what we are discussing here.

It is important to note that a building elevation is always drawn as if you are standing back away from the structure. The ground plane is always cut through in section because the ground plane is continuous and you can never see it in elevation.

Internal elevations are usually drawn of individual rooms. The begin from inside the line of the section cut to show the internal materials, objects and finishes on a wall or vertical surface.

Drawing A Plan, Section And Elevation

If we were to draw a set of plans, sections and elevations of the capsicum, we would be drawing an existing object. As an architect, we might be drawing an existing building or structure. However, more likely we are drawing something that does not exist, and so are using these drawings as a way to help us design.

When we draw plans, sections and elevations we are drawing the object or structure in true, real proportions of height, length and width measurements. We must be very exact and measure everything carefully or our drawings will look distorted. We must also be sure that our drawing does not have perspective and is representing flat planes only.

We normally start our orthographic drawings with a floor plan so we can place our horizontal points in space. We can then work from the plan to project the sections and elevations in the vertical.

Learn more in the article titled “How To Draw A Plan Section And Elevation In Architecture.”

Things To Remember…

Hopefully, that gives you a very basic understanding of plan, section and elevation in architecture. In summary, here are a few key things to remember.

  • Plans are horizontal views. Sections and elevations are vertical views.
  • Plans and sections focus on the “cut.” Elevations focus on the vertical planes.
  • Elevations are labelled with numbers or compass directions North, South, East and West based on the direction they are facing, not the direction you are looking at them. Sections are labelled with letters.
  • Sections and elevations are always drawn with the ground plane cut through in section.
  • Elements cut in plan and section (ie. wall type and thickness, doors, windows) should be drawn the same way, as they are representing the same thing.
  • Internal elevation information is secondary in sections and should generally be indicative.
  • Plans, sections and elevations should be accurate, proportional and show the same measurements and points in space throughout each drawing.

Until next time…

Liz at ArchiMash