From decoding technical drawings to understanding the requirements of each heavy construction project, blueprint reading is a key first step in construction project planning.
With effective blueprint reading skills, your team can demonstrate its expertise during the estimating and bidding process. Let’s review some key steps in how to read blueprints for civil construction estimates:
1. Search the Ingredients
Title blocks, legends, notes, and scales comprise the key components of any blueprint. And each section contains important subparts.
Usually located in the lower right corner of the blueprint, the title block may also appear in a thin band around the first page. In it, you’ll find the project name; drawing title; the name of the person or organization that created the blueprint; date; and the dimensions or scale. Near the title block, you may find a revision block detailing any changes to the blueprint, who authorized them, and related notes.
Look closely at sections labeled notes, key, or legend. Information here provides details specific to the project, including symbols, abbreviations, and other conventions used in the drawing.
The largest part of any blueprint package is its many pages of drawings or views. These include plan views, elevation views, section views, and detail views, and additional construction sheets.
2. Decode Symbols
A series of symbols and annotations on civil construction play a crucial role in conveying information to contractors, surveyors, and other professionals involved in the project. Unlike standard construction, architecture, and building symbols, civil construction blueprints will include several terms and symbols that are more technical in nature.
In civil construction, you’re likely to find topographic symbols such as contour lines, spot elevations, and related benchmark points. Geotechnical symbols, meanwhile, can note the quality and types of soil in the construction area. Along with erosion control details, that information can affect soil boring decisions.
Other symbols might include:
- Grading symbols indicating areas where the work might involve cutting into the ground (excavation) or filling (adding material).
- Slope symbols Illustrate the desired slope of the terrain.
- Road and Highway Symbols show a road’s centerline, paths, alignment, lane markings, traffic signs and signals. Utility symbols depict types and locations of water pipes, sewer lines, stormwater drainage pipes, gas lines, electrical conduits, telecommunication lines, and more.
- Surveying symbols indicate land survey points along with elevation benchmarks for reference. Alongside those, landscaping symbols may mark existing or proposed trees, shrubs, or other vegetation and may note fences, paths, or other hardscape elements.
- Structural symbols indicate locations of any bridges, culverts, and other major structures, existing or planned, or permanent structures.
3. Discover details in the drawings
Now it’s time to dive into the meat and potatoes of the blueprint package. As the largest and most comprehensive section, the stack of drawings features all the detail you need for every use of the symbols shown on the blueprint. Fortunately, these pages usually include at least one key or legend to help you navigate each of them.
One section of pages will outline the site plan, with details on the layout of the project area. Within those pages, you’ll find the grading plan, illustrating the topography, any elevation changes, and grading of the land on which the project takes place. This knowledge helps ensure proper foundational support and drainage.
Drawings of utility and roadway plans might feature the orientation of the project relative to existing or planned water lines, power lines, drainage, roads, sidewalks, traffic control signage, and the like. Some plans may also include drawings of landscape plans or erosion control plans.
Some people find the views to be the most exciting of the drawing pages. That’s where you find cross-section views from various angles, collectively illustrating the full anatomy of the project.
4. Know your construction sheets
The construction sheets are the alphabet soup of construction projects. By memorizing the corresponding letters to each category, navigating references to them throughout the blueprints will be a breeze. As a civil contractor, your focus will be on the civil plans, but there are details about the project embedded in other important sheets that may be relevant to your part of the project.
General (G): The G pages or general construction sheets typically relate to the overall project coordination. They feature important notes that might apply to various aspects of the project across each component of construction.
Survey/Mapping (V): Survey Mapping sheets include details about the collection of points to define a physical surface’s features (natural, manufactured, or both).
Geotechnical (B): Geotechnical reports provide specific information on subsurface soil, rock, and water conditions, along with the design and construction recommendations by the geotechnical engineer.
Civil (C): Civil construction sheets provide information about site grading, erosion & sediment control, stormwater management, landscaping, or other site details.
Landscape (L): The landscape construction sheets include plans, sections, and details on constructing the landscape elements of the project. These are usually coordinated between the civil and landscape engineers and contractors.
Other parts of the project that may or may not be relevant to you as a civil contractor are:
Electric (E): Electrical sheets include details about information electrical systems throughout the project. These might feature everything from equipment, grounding, and wiring diagrams to specific fixtures.
Plumbing (P): Here, you’ll find diagrams, symbols, and measurements related to plumbing systems within and surrounding the project area.
Mechanical (M): These sheets focus on the overall Mechanical systems that either feed into the project area or will be installed at the site. These might include equipment schedules and details about components such as HVAC or other systems serving the project.
Structural (S): Various sheets in the blueprint package provide detailed information about each structural component of the project. These structures might range from foundation elements to towers and beams or columns and load-bearing structures.
Architectural (A): Architectural sheets focus on the design and layout of any buildings within the project site. These include floor plans, elevations, cross-sectional views, and other design and finish elements..
5. Quantify materials & resources
In addition to understanding the technicalities of the project, blueprints include notations indicating required equipment, materials, labor, and other resources for the project.
Plan with confidence. Utilize takeoff methods to measure, quantify, and calculate the required amount of each piece of equipment or materials such as steel, concrete, and other components. TIP: TCLI’s Estimating Link® makes this easy and accurate: Through our partnerships with trusted takeoff providers, contractors who use Estimating Link® find this process intuitive. After determining takeoff quantities, simply enter measurements in a given bid item/work task, and the program completes the calculations for you.
Learning how to read blueprints also helps with identifying potential risks and uncertainties of a project. This understanding helps in developing realistic contingency plans and risk assessments, which are integral parts of the estimation process.
Blueprint reading saves time & resources
In summary, blueprints are much more than visual guides that enable accurate analysis of a project. By thoroughly understanding each part of the blueprints, you can assess complexities, identify potential challenges, and propose cost-effective solutions. Ultimately, knowing how to read blueprints with precision increases your level of accuracy and reliability during the construction estimating process.
TCLI is built on knowledge, experience, and passion for civil and heavy construction. It’s our goal to provide resources that make processes in the construction business simple and straightforward. How can we help?
