The construction industry has a particular reputation for being a tough environment in which brute force takes priority over calculated thinking; however this image is far from appropriate. There is a huge amount of work that goes on behind the scenes of the demolition and construction industry which is firmly rooted in the academic world.

One part of this unnoticed work is site surveying, or more precisely pre-demolition and post-demolition topographical surveying. This kind of work calls for a good balance of specific technical know-how as well as experience of the industry and a natural intuition for the intricacies of the job.

Topographical Surveys

A topographical survey is a report of the actual features of a particular plot of land. The aim of a topographical survey is to map the naturally occurring and man-made traits of a particular landscape to a high degree of precision.

Topographical surveys can be carried out on a very broad range of environments, from open countryside to urban developments and across a variety of elevations and land surfaces. Surveys can be developed to take into account a great many factors, such as ground conditions or vegetation, and as such can be used for a multitude of tasks.

Common Applications for Topographical Surveys

Probably the most widely used, and most generally recognised application for topographical surveys is cartography, or map making. Modern day maps include a great deal of detail about the terrain they relate to, including waterways, elevations and ground surface, all of which will have been gathered via a topographical survey. This information is also being made available online.

Topographical surveys also have a major role to play in the construction business. When individuals or companies are looking to build any kind of structure they will need to undertake extensive surveys as part of the design stage of the project.

Surveys also play a key safety role in primary industries like mining, or in other industrial sectors that interact with the terrain, such as demolition and infrastructure. Organisations in these industries will use surveys to plan their projects, but also to be sure that they can guarantee the safety of their workforce on site. As a result, topographical surveys are often a legal requirement for these types of projects.

Many construction and demolition businesses within this country perform demolition surveys for jobs they are working on.

Types of Survey

The arena of topography covers a large number of physical features so it is important to identify what form of topographical survey is appropriate for a particular situation. A few of the more common types of survey required for construction sites are discussed below.

“Lie of the land” Surveys

These types of topographical surveys are fashioned to create an overview of the physical characteristics of any given plot of land. Although the data gathered by the survey will be very accurate, and can be very extensive, the objective of these surveys is to provide a site summary.

These surveys will generally include a boundary survey that sets out to determine the extent of the site and spotlight any specific restraints that are determined by the geography of the site. They may also include a level survey that will measure the elevation of the terrain and the numerous gradients that exist.

Building Surveys

Building surveys are more typically concerned with man-made structures on a site, including the surveying of special machines and even infrastructure features. This type of survey is more regularly associated with the demolition industry because it can give a detailed plan of the building to be demolished. It may be used for other projects as well.

A building survey will probably include a measured survey, which entails creating a comprehensive plan of the exterior and internal proportions of a structure. Depending on the requirements of the job, a measured survey could provide simple building “footprint” measurements, or might produce a very detailed plan of the structure.

Content of a Topographical Site Survey

A survey of a demolition site will almost definitely include the details gathered by the types of boundary and building surveys described above. This information will be needed so the demolition firm can plan a demolition that is both adequate and secure.

Surveys will often contain information about the utility services that are present on a site before any demolition or construction work happens. This is an important safety factor because any unmonitored damage to pipes and cables carrying water, gas and electricity could be very dangerous. The information could also be used to plan new structures, based upon the existing availability of these utilities.

Another aspect of the site study will often be an inventory of materials on the site. This type of study will be a quantity survey of the various types of materials that can be located on site, for example, tiles and masonry, concrete that can be utilised as hardcore or even timber. By getting an accurate audit of site materials the construction firm can more precisely determine the need to import building resources, or they can re-use the materials on a different project.

Nearly all construction sites require topographical demolition surveys now laws and safety have become critical requirements.

Importance of Site Surveys

Perhaps the most significant reason to undertake a topographical site survey is to ensure the health and safety of the people who will be working on the site. The industrial sectors that most frequently call for site surveys are risky enough as it is without having to be concerned about the condition of the ground on which they are working. Taking a detailed topographical survey can help to eliminate safety risks of this nature.

Another critical reason to get a proper survey done is to highlight any potential difficulties that may arise because of the physical characteristics of the region. Certain things will not be evident on the surface of the site and will only be discovered once digging or demolition has begun.

The inventory of site materials, as previously stated, can be of great value to a demolition or construction organisation working on a project. Not only are building materials themselves costly, but importing them to the site could be a very expensive task in itself. Any time that material can be recycled on site provides an opportunity to save development time and money. Only by taking an exact audit of these materials can a company properly plan its imported material requirements.

Topographical surveys can also highlight other areas that will be of use to the project planners. For example, if the gradients on a site would be prohibitive to certain vehicles or machinery then a new access route or alternative machinery will have to be found.

Positioning of Survey Control

During the surveying and construction stages of a construction project, the apparatus required for the physical surveying of the site and control of the survey information will often be kept on-site. This is clearly a problem when it comes to the demolition stage of a project since the machinery is both expensive and sensitive. It is therefore sensible to move this equipment off-site during demolition.

Once the demolition has occurred and the site has been deemed safe for staff to return to it, the surveying equipment can be restored to its original position on site. This will allow for efficient data gathering to take place for a post-demolition survey, and retains a single point of contact for anybody who needs the topographical survey information. Most surveying firms will oversee this redeployment.

One of the more specialist areas of industrial demolition concerns the removal of dangerous substances that may be damaging to the environment.

Who can Perform Site Surveys?

Since topographical site surveys can play such a vital role in the success or failure of a building or demolition project it is vital that they are undertaken carefully by the right people. There are different branches of site surveying and each one will have specific qualifications associated with it.

When choosing a company to undertake the surveying work necessary for your project it will be sensible to choose a company with a good reputation and a proven track record. Ask to see examples of their previous work and try to get feedback about their performance on past projects.

Who will use the Survey Information?

Once an adequate level of information has been accumulated by a site survey it needs to be handed out to the appropriate people on-site. Who gets which pieces of information will largely depend on the job roles being executed, but can also rely on the stage that a project is at.

Project Planners

Project planners will generally require access to all of the information gathered by a topographical survey, although they will particularly need to use information about the physical relief of a site before the design phase, and a site materials record before they can prepare the construction phase.

Demolition Experts

Demolition businesses will want to know about the internal and external characteristics of any building or structures that they are arranged to take down. Whilst every job will have individual requirements, demolition workers will generally need to know about the fundamental structure of a building and the materials it is made out of.

Site Engineers

Construction engineers on-site will be mainly interested in the survey information about the relief and topography of the terrain. It is usually the case that they will want to assemble on a flat surface, so they will use information about the natural lay of the land to calculate what work will be required to create a stable foundation for any building.