Plans provide a graphic representation of a building or object, together with basic information on dimensions, components and structural details.

We've looked briefly at the graphic elements in the previous lesson, so now let's turn to the other items of information shown on a plan.

Title block

The title block is generally at the bottom of the page on the right hand side.

It contains the title of the drawing, name of the client, name of the architect, builder or contracting company who drew it, date it was drawn, scale and version number.

The architect or builder may also add other information, such as their company logo, spaces for people's signatures and copyright details.

Scale

The scale of the drawing refers to the ratio used to reduce the size of the real-life building or object down to a size that can be drawn conveniently on a piece of paper.

Most building plans are printed onto A3 paper, so a scale of 1:100 is generally used for floor plans.

This means that every 1 mm on the plan represents 100 mm on the full-sized object.

However, other scales are typically used for different types of drawings.                                                                    
Below are the most common scales used for A3 plans.

You'll find more information on the metric system in the unit: Making measurements.

Dimensions

All dimensions in building plans are shown in millimetres (mm).

Dimension lines are used to show the starting and finishing points of a particular dimension.

It is normal practice to put overall measurements on the outside dimension line and more detailed internal measurements on the inside lines.

Legend

Plans use lots of abbreviations and symbols to indicate particular features.

Obvious features - such as windows, doors, wardrobes and bathroom fixtures - are shown using standardised symbols, which generally don't need any explanation in a legend.

However, industrial plans and complex buildings often have specialised or unusual inclusions.

To avoid cluttering up the drawing with terms or phrases written out in full, the symbols and abbreviations used are explained in a legend to one side of the drawing.

Below are some of the more common abbreviations that might appear in a legend.

Finishing Schedule

In commercial projects, it's common for rooms to have similar layouts and products installed, but with different finishes or colours.

In these cases, a 'Finishing schedule' will let you know which colour goes where.

Drawing number

The drawing number is a reference number used by the architect or builder to distinguish the project and working drawing being shown.

Sometimes the version control is built into the drawing number, such as '.1' on the end of the number to indicate Version 1.

However, it's more common to have a separate version control number or date in a separate box in the title block.

Always make sure you're referring to the most recent version of a plan unless you've been instructed otherwise.

Sometimes clients change their mind about certain details, or discover that particular materials are not available or the council has imposed new conditions on the project.

You don't want to end up completing an installation only to find out that the specifications had changed before you started and you weren't aware of it!