Surveying plays a crucial role in construction, laying a strong foundation for accurate and durable worksite development. Construction surveying requires a different level of expertise involving mapping and measuring the site and surrounding of the upcoming residential or commercial infrastructure. Constructing surveyors perform horizontal and vertical surveying to make sure that an infrastructure is aligned with the approved plans and specifications.
Without proper and timely surveying, the project is likely to have significant errors in many aspects including mason line, resulting in costly rework. The survey team collects and reviews essential data required for proper planning, drafting and execution.
For an individual or a professional investor, it is important to understand the nuances and aspects of surveying as well as roles and responsibilities of surveyors. The survey team must have expertise and experience in their niche to prevent mistakes and ensure error-free outcomes.
In this article, we will focus on different aspects of construction surveying including types of surveys, their features and challenges along with the best practices to get the job done right.
Table of Contents
Types of Construction Surveying
At many worksites, surveyors are usually assigned with the responsibilities of breaking ground. However, their roles don’t start with that phase; rather they get involved in the project right from the beginning with their accurate assessment of functionality of the site for the rest of the infrastructure.
In the next section, we will explore a few types of construction surveys and highlight some aspects of the job.
Control Survey
Project control is one of the most vital roles that surveyors play on the worksite. Before the construction starts, surveyors figure out a coordinate that will function as the horizontal control point and establish a Benchmark as the vertical control point. All other markings or points are measured in respect to these two places, ensuring accuracy of the build.
Topographic Survey
It is also referred to as “Topo”. The study explores a detailed map of the contours and features of the land earmarked for the project. Both natural and man-made elements are considered for comprehensive surveying. Usually, a topo is done even before the project takes off, to determine feasibility of the worksite.
Design Plan Survey
These surveys gather details about the existing worksite conditions with the objective of cross-checking drafts and drawings as well as primary surveys for accuracy verification. This survey is aimed at identifying discrepancies and correcting them before the project starts.
Layout and Staking Survey
After a set a drawing is confirmed accurate to the specified worksite, surveyors mark the location of the intended structure, highlighting its functionalities and features. These serve as a guideline for crew members where the build will come up.
Monitoring and Adjustment
Comprehensive surveying always involves monitoring throughout the project, which helps the team recommend adjustments and/or reworking as needed.
As-Built Surveys
After the build is complete, surveyors document the actual locations of the constructed features. This is done to make sure that the construction is aligned with the design. The documented surveys are handed over to project stakeholders as a reference for future expansions, renovations and maintenance.
Challenges of Surveying
An incorrectly placed or built structure often poses risks to workers, residents and pedestrians. These structures often collapse, partly or completely. And when this happens, the constructors and surveyors are equally blamed for their irresponsibility though many times, mistakes happen due to miscommunication between different parties involved in the project.
However, this is not to whitewash the failure of surveyors and/or constructors to conform to standards for quality control.
Surveyors often come across different challenges regarding construction designs, control points and busts. Let us explain each of them.
Construction Design Errors
A common error during construction surveying is overlooking inconsistencies in alignment and elevation. To a surveyor, one of the first and key steps is to check for errors in designs. After they visit the construction site, it’s important to ensure the plans are up-to-date and precise, projecting the topography of the site in question.
Even a minor mistake can lead to major and irreversible/expensive structural issues, it is surveyors’ responsibility to verify their onsite plans and measurements.
Control Point Maintenance
Due to the dynamic nature of construction sites, it’s not easy to maintain horizontal and vertical control points. Surveyors often face different challenges from environmental conditions to human interferences, both of which are unwelcome and detrimental to timely and precise execution of the projects.
For example, a heavy wind or devastating flood can cause a deficit in raw materials. People in the neighbourhoods may also oppose construction, claiming that it would cause environmental damage or encroach on their privacy. In either of the cases, this may delay the project for months or years and even stop it from coming into fruition.
Control points surveying usually needs a clear line of sight while using total stations and laser tools. Using GPS or GNSS for surveying, however, does not require a clear line of site. With progression in construction, new materials or structures can block the lines of sight partially or completely, causing difficulties using the existing control panels.
Sometimes, a surveyor may have to evaluate and establish new points of control throughout the project to keep pace with evolving demands.
Busts
A bust refers to an error in elevation or alignment. It is often caused due to a high-stress work environment. Even an inch of error (referred to as busting in this context) can lead to incorrect heights for major structures and adversely affect the structural integrity of the intended building.
Bust also happens due to incorrect measures when placing important tie-ins for functionalities, causing delays and costly rework.
Best Practices for Construction Surveying
A surveyor does a meticulous job. He may need several checks to prevent errors. There are several ways to help a team manage their survey process and complete the steps in time.
Timely and accurate surveying requires:
Ø Focusing on details
Ø Preparing documents
Ø Frequent collaboration
Wrapping Up
Surveying is indispensable to any type of construction. It provides the most basic data that can guide project supervisors and workers to complete the work in time and without errors. Construction surveying involves a blend of theoretical knowledge, practical skills, experience, excellent communication skills and attention to detail and, requiring involvement of certified professionals for the work.
