Topographical Demolition Site Surveys

The construction industry has a certain character for being a tough atmosphere in which brute force takes priority over calculated thought; however this impression is far from appropriate. There is a substantial amount of work that goes on behind the scenes of the demolition and construction sector which is firmly rooted in the academic arena.

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

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 chart the naturally occurring and man-made traits of a specific landscape to a high degree of precision. Whilst topography itself may refer to the surface of any object, it is more commonly associated with the surface of the planet.

Topographical surveys can be carried out on a very wide range of landscapes, from open countryside to urban areas and across a variety of reliefs and land surfaces. Surveys can be developed to take into account a great number of factors, such as ground variables 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 amount of detail about the landscape they relate to, including waterways, elevations and ground surface, all of which will have been obtained via a topographical survey.

Topographical surveys also have a key role to play in the construction business. When people or organisations are looking to construct any kind of structure they will need to perform extensive surveys as part of the design stage of the project.

Surveys definitely play a key safety part in primary industries like mining, or in other industrial sectors that interact with the land, such as demolition and infrastructure. Organisations in these industries will use surveys to plan their projects, but also to ensure that they can ensure the safety of their workforce on site.

Most construction and demolition companies within the UK perform demolition surveys for projects they are working on.

Types of Survey

The arena of topography addresses 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 reviewed below.

“Lie of the land” Surveys

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

These surveys will usually include a boundary survey that sets out to determine the extent of the site and highlight any particular 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 equipment and even infrastructure characteristics. This type of survey is more commonly associated with the demolition sector because it can give a detailed plan of the structure to be demolished. It may be used for other projects as well.

A building survey will probably include a measured survey, which involves creating a comprehensive plan of the external and interior dimensions of a building. Depending on the requirements of the project, a measured survey could provide simple building “footprint” measurements, or might produce a highly detailed plan of the structure.

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 the demolition firm can plan a demolition that is both adequate and secure. Often these surveys will also be legally required.

Surveys will often include information about the power services that are present on a site before any demolition or construction work takes place. This is an essential safety aspect since 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 inventory of resources on the site. This type of survey will be a quantity survey of the various kinds of materials that can be located on site, for example, tiles and masonry, concrete that can be utilised as hardcore or even wood. By taking an accurate audit of site materials the construction company can more precisely determine the need to import building materials, or they can re-use the materials on a different job.

Performing a rigorous and comprehensive house demolition survey ensures the protection of residents in the immediate vicinity of the work site.

Importance of Site Surveys

Maybe the most important reason to perform a topographical site survey is to ensure the health and safety of the individuals who will be working on the site. The industries that most commonly call for site surveys are risky enough as it is without having to worry 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 identify any potential problems 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 uncovered once digging or demolition has started. By then it may be too late to resolve these problems, or at best they will be costly problems to solve.

The inventory of site supplies, as previously stated, can be of great benefit to a demolition or construction enterprise working on a project. Not only are building materials themselves expensive, but transporting them to the site may be a very expensive task in itself. Any time that material can be recycled on site offers an opportunity to save development time and funds. Only by taking an accurate audit of these materials can a company properly plan its imported material needs.

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

Positioning of Survey Control

During the surveying and construction stages of a building project, the equipment required for the physical surveying of the site and control of the survey information will often be stored on-site. This is clearly a problem when it comes to the demolition stage of a project since the machinery is both costly 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 data collecting to take place for a post-demolition survey, and maintains a single point of contact for anybody who requires the topographical survey information.

The types of companies which require plant demolition have usually worked alongside demolition firms on jobs in the past.

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 venture it is critical that they are undertaken thoroughly by the correct people. There are different branches of site surveying and each one will have unique certificates associated with it.

When choosing a company to undertake the surveying work necessary for your project it will be wise to choose a business 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 previous projects. It may also be worth considering how a company can deliver the survey information, i.e. in 3-D models or CAD ready formats, for ease of integration with other members of the project staff.

Who will use the Survey Information?

When an adequate level of information has been gathered by a site survey it needs to 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. There will be less need for materials information half way through construction for example.

Project Planners

Project planners will usually need 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 record before they can plan the construction phase. The more information that can be made available to project planners will aid the smooth running of the venture.

Demolition Experts

Demolition organisations will want to know about the interior and external properties of any building or structures that they are arranged to take down. Whilst every project will have different requirements, demolition experts will generally need to know about the fundamental framework 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 normally the case that they will need to assemble on a flat surface, so they will use details about the natural lay of the land to determine what work will be needed to create a steady footing for any structure. They will want this information prior to and in the course of the construction stage of a project.