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Now your house plan blueprints have arrived.  What do you do next?


First, Understand the Steps Involved in House Construction


Before you dive into your blueprints, it is best to understand the key chronological steps behind turning a blueprint into a house. Blueprints are the way the designer communicates with the builder to construct a house.  Once you understand the steps, it will become that much easier to “read” the blueprints themselves.

In general:

•      The land needs to be cleared.

•      The house foundation needs to be dug consistent with the location on the site plan of your building lot.

•      Concrete needs to be poured.

•      Framing needs to be laid to attach the wood frames of your house to the foundation.

•      The first floor needs to be framed and plywood sheathing attached.

•      First-floor walls need to be constructed with openings framed for windows.

•      The next floor, if needed, is then constructed.

•      The roof then needs to be framed and plywood sheathing attached.

•      The exterior materials and windows need to be applied.

•      The electrical wiring, plumbing, and ductwork is placed in walls.

•      The heating and cooling systems are installed.

•      Then the cabinets, fixtures, and interior appointments are installed.

•      Also, there is the work to tie water, electrical, and sewer to your house.


Remember That House Plan Blueprints are Drawn to Scale

When looking at the print drawings, remember that they are drawn to a scale so that if any specific needed dimension is missing, the contractor can scale the drawing to determine the right measurement. The main floor plans are generally drawn to 1/4" scale, which means that every 1/4" on the plan equals 1' in actual length. Other details, such as framing layouts or built-in details, may be drawn at another scale as 1/8”. The scale of each drawing is usually detailed beneath the drawing or somewhere on the page, usually next to the title.


Reviewing the House Plan Blueprint Pages

The pages of your home design blueprints typically will be ordered by the way the house will be constructed.

Foundation Plan
The foundation plan will depend upon the design selected.
 Typically, the foundation will be a slab, crawlspace, full basement, or walk-out basement. The basement or foundation plan delineates the location of bearing walls that will support the structure. It also identifies locations of footings, steel (rebar) placement, hurricane strap placement, and other structural elements that are required to support the loads of the upper floors.

Floor Plan(s)
A floor plan layout on blueprints is basically an overhead view of each floor of the completed house. You'll see parallel lines that scale at whatever width the walls are required to be. Dimensions are usually drawn between the walls to specify room sizes and wall lengths. You'll also see on the floor plan locations of fixtures like sinks, water heaters, furnaces, etc. Among the walls and dimensions you will often find notes to specify finishes, construction methods, or even symbols for electrical or to reference cross sections. You can expect floor plans to be drawn at 1/4” scale.
Exterior Elevations
Elevations are a non-perspective view of the home. These are drawn to scale so that measurements can be taken for any aspect necessary. Plans include front, rear, and both side elevations. The elevations specify ridge heights, the positioning of the final grade of the lot, exterior finishes, roof pitches, and other details that are necessary to give the home its exterior architectural styling. You can expect elevations to be drawn at 1/4” and 1/8” scale.
Kitchen and Bath Elevations
The kitchen and bath elevations show the arrangement and size of each cabinet and any other significant fixtures in the room. These drawings give basic information that can be used to create customized layouts with a cabinet manufacturer.

Miscellaneous Details
These are included for many interior and exterior conditions that require more specific information for their construction. 

Electrical Layout
Electrical layouts are sometimes on a separate page to make reading them a little easier. The layout will show locations of light fixtures, fans, outlets, light switches, etc. There is usually a legend on the page, which explains what each symbol
 represents. There may be such legends for heating systems, door swings and sizes, or even to specify certain finishes.

Framing Drawings
The framing drawings are also drawn to scale and outline the layouts of items such as floor joists and trusses, beam locations and other structural requirements. Framing layouts don't usually get into the details of each stud location in the walls because framing contractors are required to follow certain rules and regulations to ensure that the home meets the required building code specifications. However, there are often cross sections within the plan pages that outline the general methods of wall construction or floor assembly.

Plumbing and Mechanical Systems
These systems are generally not covered extensively on the blueprints other than locations of fixtures and main service lines. If you are going to the expense of more complicated heating systems, such as
 in-floor radiant heat or even an engineered forced-air system, these drawings need to be completed by a heating or plumbing specialist.

Cross Sections and Details
Overhead views or floor plan views of the structure don't always provide enough information as to how the home is to be built. Often, cross sections or details will explain certain special conditions more appropriately. A cross section is basically a view of the home as if it were sliced down the center. This allows you to view the home from the side and understand a little better the relationships of varying floor heights, rafter lengths, and other structural elements.

These are the basics to reading a house plan. Keep in mind, however, that what is included in plans will vary according to the designer who drew them. House plans are a very important part of the homebuilding process. It is crucial to purchase a plan drawn by a home design professional because he or she has a thorough understanding of how homes are built. If there were any terms on this page that you did not understand – or you would like a more thorough description of their meaning – please visit our construction terms glossary.



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