Topographical Demolition Site Surveys

The demolition industry has a particular character for being a harsh atmosphere in which brute force takes priority over calculated thinking; however this image is far from appropriate. There is a huge amount of work that happens behind the scenes of the demolition and construction sector which is firmly grounded in the academic world.

One branch of this unnoticed work is site surveying, or more specifically pre-demolition and post-demolition topographical surveying. This kind of work calls for a great balance of specific technical knowledge as well as experience of the industry and a genuine intuition for the complexities of the job. This article explores the ins and outs of this work.

Topographical Surveys

A topographical survey is a study of the physical features of a particular plot of land. The purpose of a topographical survey is to chart the naturally occurring and man-made features of a specific landscape to a high degree of precision.

Topographical surveys could be carried out on a very wide range of environments, from open countryside to urban developments and across a variety of elevations and land surfaces. Surveys can be designed to take into account a great number of factors, such as ground conditions or vegetation, and as such can be used for a number 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 amount of information about the landscape they relate to, including waterways, elevations and ground surface, all of which will have been gathered via a topographical survey.

Topographical surveys also have a major role to play in the construction industry. When individuals or companies are looking to build any kind of structure they will need to undertake extensive surveys as part of the design phase of the project. These surveys are often an important part of any application for planning permission too.

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

A location due for demolition tasks should undergo a demolition survey for worker safety and financial planning reasons.

Types of Survey

The arena of topography addresses a large number of physical features so it is important to determine what form of topographical survey is suitable for a particular scenario. A few of the more common types of survey required for construction sites are reviewed below.

“Lie of the land” Surveys

These types of topographical surveys are designed to create a summary of the physical properties of any given plot of land. Although the data collected by the survey will be extremely accurate, and may be very extensive, the purpose of these surveys is to provide a site summary.

These surveys will usually incorporate a boundary survey that sets out to determine 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 numerous gradients that exist.

Building Surveys

Building surveys are more typically concerned with man-made constructions on a site, including the surveying of special equipment and even infrastructure features. This type of survey is more regularly associated with the demolition sector since it can give a detailed plan of the building to be demolished. It can 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 interior proportions of a building. Depending on the requirements of the project, a measured survey could provide simple building “footprint” dimensions, or might produce a very detailed plan of the structure.

Content of a Topographical Site Survey

A survey of a demolition site will almost always include the details gathered by the types of boundary and building surveys mentioned above. This information will be needed so that 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 takes place. This is an important safety aspect because any unmonitored damage to pipes and cables carrying water, gas and electricity might be very dangerous.

Another aspect of the site survey will often be an audit of materials on the site. This type of survey 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 taking an accurate audit of site materials the construction firm can more accurately gauge the need to import building resources, or they can re-use the materials on a different job. These surveys can be made pre-demolition and post-demolition.

Project managers may discover financial savings once topographical demolition surveys summarise supplies levels currently on-site that may be re-used.

Importance of Site Surveys

Possibly 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 dangerous enough as it is without having to be concerned about the condition of the ground on which they are working.

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

The inventory of site materials, as previously mentioned, can be of great value to a demolition or construction enterprise working on a project. Not only are construction materials themselves costly, but transporting them to the site could be a very expensive task in itself. Any time that material can be reused 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 managers. For example, if the gradients on a site would be prohibitive to specific vehicles or machinery then a new entry route or alternative equipment 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 phases of a construction project, the equipment required for the physical surveying of the site and control of the survey data will often be kept on-site. This is obviously a problem when it comes to the demolition phase of a project since the machinery is both costly and sensitive. It is therefore wise 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 initial position on site. This will allow for efficient data collecting to take place for a post-demolition survey, and keeps a single point of contact for anybody who requires the topographical survey information.

Las Vegas is the setting for much commercial demolition since old resorts require flattening so that newer ones can be created in their place.

Who can Perform Site Surveys?

Since topographical site surveys can play such a crucial role in the success or failure of a construction or demolition project it is vital that they are carried out thoroughly by the correct people. There are different branches of site surveying and each one will have unique certificates associated with it.

When selecting a company to undertake the surveying work required for your project it will be sensible to choose a company with a good reputation and a proven track record. Ask to see reviews of their previous work and try to get feedback about their performance on past projects. It may also be worth considering how a company can deliver the survey data, i.e. in 3-D models or CAD ready formats, for ease of integration with other members of the project team.

Who will use the Survey Information?

When an adequate level of details has been accumulated by a site survey it needs to be passed 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. There will be much less need for materials information midway through construction for example.

Project Planners

Project planners will usually require access to all of the information collected by a topographical survey, though they will particularly need to use information regarding the physical relief of a site before the design phase, and a site materials inventory before they can plan the construction phase.

Demolition Experts

Demolition companies will want to know about the internal and external properties of any building or structures that they are set to take down. Whilst every job will have different requirements, demolition experts will generally need to know about the fundamental structure 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 site. It is normally 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 determine what work will be required to create a steady footing for any structure. They will want this information before and during the construction stage of a job.