Quantity Surveying is usually a client-led profession where the overall role of the Quantity Surveyor is to respond to the needs and requirements of the client. The line of the QS skills development is, therefore, largely relied on the ever-changing needs and requirements of the project owners. For the QS to keep up with these continuous changes in the construction field, all licencing, regulatory and registration boards usually prescribe that an individual must adhere to a Continuing Professional Development (CPD) program in the course of their professional practice.

The main role of the Quantity Surveyor in construction projects includes estimating and cost planning, procurement advice, measurement, preparation of bills of quantities and tender documentation, construction cost control, preparation of valuations, payments, contractual claims and final accounts. However, IT advancements in the field of Building Information Modelling/Management (BIM), Building Energy Modelling (BEM) and estimating software is playing a key role in disrupting the construction industry with particular impact on the duties of the design teams, notwithstanding those of the modern quantity surveyor.

What is BIM?

The modern construction industry clients want their buildings to be safe, to look good and provide comfortable living environments for their occupants while consuming less energy in their operations. These complex client demands coupled with more strict building performance by-laws and regulations have given rise to the invention of more innovative building design and engineering approaches which include BIM implementation.

Building Information Modelling (BIM), sometimes referred to as Building Information Management (BIM), is viewed as a process for creating and managing information on a construction project across the project life cycle in a collaborative manner. BIM is a tool and a repository for handling and storing project data and all the related information that can be used throughout the project life cycle. It forms a reliable basis for making project-based decisions during the life cycle of the project.

Ideally, BIM is not software as most people view it. Instead, it should be looked at as a group of technologies that are applied to integrate people and their working processes in a way that restructures the traditional workflow that embraced passing of information to the next party to one that encourages sharing of information among the project participants.

BIM & The Quantity Surveyor

From 2D Computer Aided Drafting (CAD) to 3D CAD and BIM, all these developments have been aimed at automating the functions performed by the various professionals involved in a given construction project. Adoption of BIM by building designers make more accurate 3D models is one of the key drivers that has led to the quantity surveyors finding it necessary to embrace BIM in their work (although it has not gained widespread adoption).

Compared to other construction professionals, quantity surveyors have shown a slow uptake of BIM technologies. A survey done in the UK by the Royal Institution of Chartered Surveyors (RICS) indicated only 10% of the quantity surveyors had been involved in BIM. With most research literature indicating BIM in architects’ and designers’ practices, less literature points to the integration of BIM in the Quantity Surveying practice. The Kenyan context might be similar or slightly different.

Some quantity surveyors believe that if they accepted BIM practice most of their functions will be automated and it will lead to technological unemployment. This is just a misconception about BIM and associated technologies as no single technology can replace the human judgement required to offer professional QS services. Quantity take-off can be automated (which is an advantage to the QS), but contract management, technical and legal advice cannot be automated!

5D (fifth dimension) BIM is the level of BIM implementation that adds a dimension of cost to building models permitting the generation of cost estimates at an instant. The quantity surveyor develops a cost database that gets integrated into the shared model. Quantity take-offs, real-time cost modelling, cost planning and value engineering can, therefore, be automated. This is because BIM offers the capability to automatically generate quantity take-offs and measurements directly from a digital model of a building, a process that traditionally is very time-consuming for quantity surveyors.

Possible Changes

Most quantity surveyors have been operating with the assumption that BIM is all about 3D modelling for the architect. If construction industry stakeholders and policymakers embrace BIM through its adoption, this notion is going to change. The full potential of BIM will see quantity surveyors start participating in the process of collecting, analysing and sharing the right cost data for building 5D BIM models. This will see more quantity surveyors get involved innovatively in all the stages of a project exchanging information with other stakeholders and working on the solution for the client’s situation. This will improve the whole building process in the long-run.

The quantity surveyor’s core functions of measurement and bills of quantities preparation which involves quantity take-off will be revolutionised. There usually is extreme pressure when the QS is working on large and complex projects producing cost estimates and bills of quantities from 2D drawings. If details are missed in those drawings, assumptions made to come up with these estimates sometimes leads to costly cost overruns when detailed designs are produced and reworks and sometimes delays are encountered due to discrepancies.

The above-described situation is going to become better with model-based estimating. Quantity take-off will be automated. The QS will be working on a live model, inputting cost information directly to the shared model. Any changes in the model will be reflected directly to the quantity surveyor’s material and cost schedules reducing the need to go back to the drawing board when the design changes. Accurate cost estimates based on the documented productivity of construction workers can then be used to estimate the construction period.

It is also important to note that BIM will impact the teaching of quantity surveying in universities and colleges. The quantity surveying curriculum will need to be revised to integrate BIM in the syllabus. By taking this step, the institutions of higher learning will be playing a very key role in ensuring all quantity surveying graduates are prepared for the industry. It will be a huge effort towards improved implementation of BIM technology in quantity surveying practice.

5D BIM adoption is going to cause changes in the way quantity surveyors operated before. Some of the responsibilities they hold will start to shift with BIM’s cost management functions allowing the QS to delve into other aspects of cost management that they wouldn’t have been involved before due to their complexity. Quantity surveying firms will have to choose BIM-based estimating tools depending on their workflow, available software and pricing databases used in their practice to be part of a BIM-based project and to benefit from the advantages of its implementation.

Opportunities & Threats

There have been ongoing discussions on the fate of the quantity surveying profession with the advent of BIM that produces construction quantities in an automated process. It is important to point out that BIM presents huge opportunities for the QS in the area of cost estimating and quantity take-offs.

In particular, 5D cost estimating allows early design models to be linked to a software (e.g. CostX) that enables the QS to extract quantities at the initial stages of a construction project. Using his developed cost database, the QS links the quantities to obtain a very accurate cost estimate. The speed and accuracy of this process enable the cost managers to access to the right information for comparing alternative design solutions for determining a better value for the clients. Several designs can be compared at this stage in a shorter period compared to the traditional practice of tedious manual take-offs.

Also, we have seen that the production of cost estimates will be speedy due to the reduction in the time taken in performing take-offs. This will leave the project QS with more time to be dedicated to providing knowledge and expertise to the project teams making the QS role more valuable to the project.

Further, BIM is likely to enhance a broader range of QS functions in the future including automated measurement and quantification, environmental and sustainability analysis, facilities management, legal services, investment advice and quality management. There exists an opportunity for the QS who will be proficient in working in 5D BIM as their excellent skills will place them at a better position to get jobs requiring an understanding of the BIM workflow and functionality.

However, BIM integration in the quantity surveying practice threatens the survival of those who are resistant and not ready to embrace change.  Quantity surveying firms will now compete for clients based on the provision of specialised services in a timely and more productive approach. Those who will be left behind will be less competitive compared to their counterparts and might experience a reduction in the number of projects they handle as the clients will be more willing to hire the BIM oriented QS, who will offer more customised services and spent less time in the production of estimates and cost plans.

Also, hasty and a not-well-thought of BIM implementation strategy might hurt a project. It should be done after a rigorous evaluation of the requirements that the client has in mind. If any of the project parties propose to use BIM and the team misses on its appropriate implementation, it may prove costly to both parties (increasing the cost of the project and other associated risks). It is, therefore, good practice to first establish the requirements of the client and agree on a BIM execution plan that solves the client’s problems early before any implementation has started.

Key Challenges

With the appreciation that the integration of BIM in the quantity surveying practice is going to open up more opportunities by enabling the QS to perform a broader range of services as earlier indicated, its implementation is wanting. The quantity surveyors have not shown widespread reliance on BIM in their practice due to the following challenges:

Data Exchange Issues in BIM Tools: 5D BIM estimating software and modelling software produce and accept data input in different formats which put at risk the accuracy and consistency of project data exchanged. If the quality of data reaching the QS is compromised, the quality of advice offered in reliance to it will end up being compromised.

Standardization Challenges: It is worth noting that BIM as both a workflow and a process is underpinned by software. Quantity surveying and estimating software that supports BIM workflow exist in the market (e.g. CostX by Exactal and BIM 360 by Autodesk, among others).

However, quantities extracted from BIM models are generated per the parameters set by the vendors of the BIM software used. Most of these software vendors do not follow a recognised standard method of measurement. Where the QS is required to follow a certain standard method of measurement, there is a need to convert and tailor the BIM extracts to suit the required presentation, data coding and building systems classifications. This lack of consistency in BIM modelling standards adopted by various estimating software vendors leads to the QS having to conform to several standards which result in inconsistencies and inaccuracies in estimates.

Substandard Quality of BIM Models: The practice of cost management by the QS depends on proper detailing of the project data by the architects and designers for the production of accurate cost estimates. However, architects and other design consultants are unwilling to provide full details of their BIM model due to the potential liability of the designers. This makes the models devoid of the required information to assist with model-based measurement and quantity take-offs. Quantity surveyors will, therefore, experience difficulties in managing and searching for the required design details to enable the production of accurate estimates.

Cost of Training & Education: BIM is a highly advanced and very sophisticated information technology. It is indeed a complex workflow that will require quantity surveying firms to commit both time and monetary resources to the training of the employees, purchase and installation of BIM oriented estimating software. Some firms may not be financially able to fund the introduction of BIM due to their small sizes. As most quantity surveying syllabuses have not incorporated BIM in their programmes, much remains to be done for BIM to gain widespread adoption and implementation in the quantity surveying practice.


The global construction industry is moving towards widespread implementation of the BIM technique. With industry players in Kenya beginning to hold more talks and seminars about BIM, it is time for the quantity surveyors to respond accordingly. The QS needs to start appreciating BIM, understanding its potential, developing and employing effective processes and tools to integrate BIM into their current and future professional practices.

Quantity surveyors are in charge of costs and work to ensure value for money to clients. With the BIM’s promise of helping them manage costs better and more accurately, our construction industry will reap huge benefits in terms of value addition from the quantity surveyors move to implement BIM in their workplaces.