The construction trade has a particular reputation for being a harsh environment in which brute force takes precedence over calculated thinking; however this image is far from appropriate. There is a substantial amount of work that happens behind the scenes of the demolition and construction industry which is firmly grounded in the academic arena. Furthermore, this unseen work is vital to the success of the more visible procedures.

One part of this unnoticed work is site surveying, or more specifically pre-demolition and post-demolition topographical surveying. This sort of work demands a good balance of specific technical understanding as well as experience of the industry and a genuine intuition for the complexities of the job.

Topographical Surveys

A topographical survey is a report of the physical features of a particular piece of land. The purpose of a topographical survey is to map the naturally occurring and man-made features of a particular landscape to a high degree of precision. Whilst topography itself can refer to the surface of virtually any object, it is more commonly associated with the surface of the planet.

Topographical surveys could be carried out on a very wide range of landscapes, from open countryside to urban areas and across a variety of elevations and land surfaces. Surveys can be designed to take into account a great many factors, such as ground conditions or vegetation, and as such can be used for a number of tasks. A few of the more common uses are discussed below.

Common Applications for Topographical Surveys

Perhaps the most extensively used, and most commonly recognised application for topographical surveys is cartography, or map making. Modern day include a great amount of detail about the landscape they relate to, including waterways, reliefs and ground surface, all of which will have been collected via a topographical survey.

Topographical surveys also have a major role to play in the construction industry. When people or organisations are looking to build any kind of structure they will need to carry out extensive surveys as part of the phase of the project. These surveys are often an indispensable part of any application for planning permission as well.

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

A site due for demolition work ought to go through a demolition survey for worker protection and monetary planning motives.

Types of Survey

The arena of topography covers a large number of physical features so it is beneficial to identify what type of topographical survey is appropriate for a particular scenario. A few of the more typical types of survey necessary for construction sites are discussed below.

“Lie of the land” Surveys

These types of topographical surveys are fashioned to create a summary of the physical properties of any given plot of land. Whilst the information 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 define the extent of the site and highlight any specific restraints that are determined by the geography of the site. They may also include a level survey that will plot the elevation of the land and the various 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 commonly associated with the demolition industry because it can give a detailed plan of the structure to be demolished. It may be used on other projects as well.

A building survey will almost certainly include a measured survey, which entails creating a precise plan of the external and interior proportions of a building. Depending on the requirements of the job, a measured survey could provide basic building “footprint” dimensions, or might produce a highly detailed plan of the structure. This information can be used to create internal floor plans and even roof plans.

Content of a Topographical Site Survey

A survey of a demolition site will almost definitely include the information gathered by the types of boundary and building surveys mentioned above. This information will be required so that the demolition company can plan a demolition that is both satisfactory and secure.

Surveys will often include information about the energy services that are present on a site before any demolition or construction work takes place. This is an important safety aspect because any unmonitored destruction to pipes and cables carrying water, gas and electricity might be very dangerous.

Another aspect of the site study will often be an audit of materials on the site. This type of study will be a quantity survey of the various types of materials that can be found on site, for example, tiles and masonry, concrete that can be used as hardcore or even timber. By getting an accurate audit of site materials the construction firm can more accurately determine the need to import building materials, or they can re-use the materials on a different project. These surveys could be made pre-demolition as well as post-demolition.

Project planners may discover financial benefits after topographical demolition surveys summarise supplies quantities currently on-site that can be re-used.

Importance of Site Surveys

Perhaps the most important reason to undertake a topographical site survey is to ensure the and safety of the people who will be doing work on the site. The industries that most frequently call for site surveys are risky enough as it is without having to be concerned about the integrity of the ground on which they are working.

Another important reason to get a suitable survey done is to identify any potential problems that may arise because of the physical characteristics of the region. Certain things may not be evident on the surface of the site and will only be uncovered once digging or demolition has started. By then it may be too late to deal with these problems, or at best they will be costly issues to solve.

The inventory of site materials, as previously stated, can be of great value to a demolition or construction enterprise working on a project. Not only are building materials themselves costly, but importing them to the site may be a very expensive task in itself. Any time that material can be reused on site provides an opportunity to save time and funds.

Topographical surveys can also identify other areas that will be of use to the project managers. For example, if the gradients on a site would be prohibitive to specific vehicles or machinery then a new entry route or alternative machinery will have to be found. Equally, a suitable site will need to be found for the base of control operations for the project. Good site surveying can help out in these less tangible ways.

Positioning of Survey Control

During the surveying and construction stages of a building project, the apparatus required for the physical surveying of the site and control of the survey information will often be stored on-site. This is obviously a problem when it comes to the demolition phase of a project since the equipment is both expensive and sensitive.

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 initial position on site. This will allow for effective collecting to take place for a post-demolition study, and keeps a single point of contact for anybody who needs the topographical survey information. Most surveying companies will oversee this redeployment.

Many towns and cities around our country need home demolition before development of modern housing estates can start.

Who can Perform Site Surveys?

Since topographical site surveys can play such a vital role in the success or failure of a construction or demolition venture it is critical that they are carried out carefully by the correct people. There are different divisions of site surveying and each one will have specific qualifications associated with it. Finding surveyors with these specific qualifications will certainly be advantageous.

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

Who will use the Survey Information?

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

Project Planners

Project planners will generally need access to all of the information gathered by a topographical survey, although they will particularly need to use information concerning the physical relief of a site before the design phase, and a site materials record before they can prepare the construction phase. The more information that can be made available to project planners will assist the smooth running of the venture.

Demolition Experts

Demolition companies will want to know about the internal and external characteristics of any building or structures that they are set to take down. Whilst every project will have different requirements, demolition workers will typically need to know about the fundamental framework of a building and the materials it is made out of. They will need this information before demolition can take place.

Site Engineers

Construction engineers on-site will be mainly interested in the survey statistics about the relief and topography of the terrain. It is usually the case that they will want to build on a flat surface, so they will use details about the natural lay of the land to determine what work will be required to create a steady footing for any structure.