Blueprints provide a map for building a home. The symbols on the blueprints tell carpenters, plumbers and electricians all they need to know about the home's design and building materials. Plumbing blueprints detail everything from the type and size of sinks to the location of gas lines, drains and vents. Plumbers may take extensive courses to learn to read all the details of a plumbing blueprint. As a homeowner, familiarity with the symbols of plumbing blueprints may help you in troubleshooting and making repairs.
Obtain a guide to the plumbing symbols on a blueprint. You will find legends online, or you may obtain books from the library that list the hundreds of symbols that might be used in a plumbing blueprint.
Spread the blueprint on a table, counter or other flat surface that will allow you to read the entire page at once. Familiarize yourself with the general layout of the house, focusing on the kitchen, bathrooms and laundry rooms, where plumbing is concentrated.
Read the schedules that accompany the blueprints. A schedule is a guide to the various symbols used in the blueprints. The schedule will specify the type of materials to be used in the particular job.
Identify the symbols for major plumbing fixtures such as sinks, showers, bathtubs and toilets. From these symbols, trace the drain lines and vents. Consult the plumbing symbol guide if you're unsure of the meaning of any symbols.
Look for other symbols for gas lines, sewer connections or water piping for radiant heating. Plumbers handle these aspects of home building, too, and they are included in plumber's blueprints.