I conducted the study to assess the level and scope of use of construction process of prefabrication and modularization and analyses how these can impact productivity based on key performing indicators. The research was conducted by a few varying methods.
The primary method was to initially email out questionnaires to various companies and individuals with the aim to gain a vast amount of responses with a vast array of firm types, user groups and firm sizes. This was to gain a fair understanding of the usage within industry from a broader fair-minded sense (including varying sized companies and varying user groups). This posed serious issues in vast number of responders not responding within the allocated period of time. As such two other methods of collecting data were used.
The secondary method was in the creation of an online questionnaire. This ensured that receivers could quickly respond without having to hand write responses and this provided a response rate of 60%. Still with a vast amount of outstanding data (predominantly from contractors) it was important to gain this information. As such the third and final method was used.
The third method of collecting data was to ring up the outstanding responders and to ask the questions over the telephone and fill in the questionnaires whilst talking to the individual. This proved successful and as such a 98% response rate from 400 proposed responders was possible.
In order to produce a balanced questionnaire, it is important to not ask leading questions or propose leading answers. This will then in turn provide the most honest responses. The key requirements of the questionnaire/survey were to
1- Confirm their Industry business type (Consultant, Manufacturer, Contractor etc.)
2- Confirm their discipline (Engineer, Architect, Contractor, Specialist contractor)
3- Confirm the size of the business (Small, medium or large). Most individuals working for a company will understand within their industry sector, how large their business is compared to others.
4- From this, asking about key indicators such as opinion on productivity, wastage, site safety, costs were important. The questions were asked based on a, yes, no answer followed by a question asking for quantification. This was important so as to be able to easily collect the data and quantify into excel for analysis.
This survey has 392 responses. Throughout the report categories such as Architects, engineers, contractors have been stated. Responders by categories are as such;
– 24% Architects – 94
– 28% Engineers – 110
– 48% Contractors – 188
o 7% – General contractor – 29
o 5% – Construction Manager – 19
o 11% – Mechanical Contractor – 44
o 14% – Electrical Contractor – 55
o 5% – Fabricator – 19
o 6% – Design Build/Other – 22
The sample use in order to represent a population has to be varied enough and large enough to ensure a firm foundation of statistics.
Terms Used and Definitions
The process of manufacturing in which general is undertook at a specialized facility. Various materials and components are joined in order to form a component part of the final installation. Industry examples include, Structural Steel Trusses, Pre-cast concrete.
Model-driven prefabrication is describing the process of using Building Information Modelling (BIM) models to enable prefabrication and the assembly of components off the construction site as well as on it.
The remote assembly (and manufacturing process) of both interior and exterior building section (I.e., walls, floor, roof) using either one or multiple material types which could include parts of systems (such as electrical, plumbing). Industry examples are entire building modules, insulated structural panels or simply curtain walling.
Permanent Modular Construction
PMC – performed in a manufacturing facility this design and construction process produces components or modules of building s that are constructed off-site to be transported to a permanent building site (generally as units on the back of lorries). This is commonly used in new education buildings on existing education sites where access and construction time frame are limited.
This is not a manufacturing process but instead the assembly or fabrication of components as the name suggests off-site. It however can be done on site but at a different location to the point of installation and is usually undertaken by skilled specialist contractors.
Building Information Model – BIM
This is the digital representation of functional as well as physical characteristics of a building/structure via a 3D model. As a shared knowledge source for information it forms a reliable basis for any major decisions during a building/structures life-cycle. Additionally, BIM refers broadly to the creating and usage of digital models in order to provide effective collaboration processes between disciplines and companies for clash resolution and to reduce the amount of problems arising on-site.
Any part of a building structure that sits above the foundations or baseline (usually ground level). This includes the structural frame, secondary structural elements, partitions, roofs and exterior walls. Elements such as basements, cellars etc are generally part of the substructure.
This can be defined as a set of ideas and processes of continuous improvements in order to minimize costs as well as ensuring maximum value to clients in every aspect of the built and natural environment such as planning, designing, construction, activation, operation and maintenance as well as recycling.
Integrated Design Process
All disciplines actively participating in all stages of design, construction and at certain times the operation and maintenance of the building. An integrated design team will generally be built up of the owner’s representative(s), Lead architect, Lead mechanical, electrical and structural engineer as well as a construction manager and or general manager (project manager). In certain projects it can potentially include future building occupants/tenants, facilities management/ maintenance staff as well as building product manufacturers and subcontractors.
Integrated Product Delivery
The construction project delivery according to a contract which asks for an integrated design process and also clarifies the responsibilities and risks born by all members of the project team (legal responsibilities).
The construction of a building (and design) to UKGBC (UK Green Building Council) regulations and requirements/standards or additionally/ alternatively a building that includes various green building elements such as energy, water and resource efficiency, potentially improved air flow and improved indoor air quality. Any project in which only contain a couple or minor amount of green building elements are not included by the definition.
This is the ratio of resources used to produce an output in comparison to the output itself. Such resources used include, labor costs, energy costs, material costs, potential fines etc.
This is usually determined by the client/ project owner and is the amount of money available to construct the project. Projects are usually put out to tender in which companies bid in stating how much in cost and time they can deliver the work. It is then the project teams responsibility to deliver the project, finished and ensuring maximum project value within a budget to the owners content.
The timeline for the events in which directly relate to the planning and construction of the project. A construction schedule and Gannt chart will outline the resources required and tasks and objectives as well as outlining the dependencies of the tasks to one another.
Centuries old-construction processes and have reborn with BIM, Modern manufacturing methods as-well as sustainability goals and recognized productivity. Over the past century these methods of construction and processes involved have gained a stereotype/stigma of cheapness and poor-quality. This now with the aid of modern techniques and changed to being a key component in improving construction productivity.
It is well known throughout the industry that prefab and modular building techniques are not new processes, 68% of those that are using these processes have done for the past 5 or more years and unsurprisingly (as its not new) 90% of players within industry are using the processes on some projects (90% of engineers, 84% contractors and additionally 74% architects).
It is anticipated that by 2020 nearly all players, 99% expect to be doing some form of prefab/modular construction projects. Currently it is known that amongst users, just over a third (40%) use it on a high level (more than 60% of projects), it is however anticipated that over the next 2-3 years usage on projects will grow moderately from 40% to 50% usage. Amongst all users surveyed, fabricators, mechanical contractors and design-builders are the highest level of current and future usage. Amongst those surveyed, the primary reason companies are not using pre-fab and modular on some or all projects is due to the architect not designing into the project. With this architect stated refusal of usage from owner/client as the biggest reason for not adopting these methods (42% for users and 57% for non-users).
Areas of Usage
There is a wide variety of commercial building-projects in which prefab and modular is being used on. Respondents are currently using it on
– Healthcare Facilities (58%)
– College/Education Buildings + Accommodation (47%)
– Manufacturing Buildings (42%)
These respondents view future opportunity and growth within Hotels, Health Care Facilities, Education and other commercial buildings such as prisons, power plants, data centres. These do vary between player type, mechanical contractors see more opportunity within power plants and hotels for example.
Within any building, prefab and modular can only be used in certain parts of the construction. From the responses it is noted most often these areas are building superstructure (35%), exterior walls 24% and MEP systems 28%.
As well as this from users, they stated that there are 3 major factors in deciding to, or not to use prefab and modular methods. These were site accessibility (62%), size and height of building (58%) and finally type of building/ building usage (54%)
User Usage Factors
When asked, responders stated productivity (87%) as the most important driver to modular/prefab construction. This was mostly important to contractors with 92% stating this as well as 75% of all responders stating they see themselves as more competitive within tenders and the marketplace by using this rejuvenated construction technique.
The beliefs of Contractors, Architects and engineers is that the factors and drivers relating to future usage will be the improvements that using prefab and modular methods can provide to cost, quality, productivity and project schedule as well as safety.
Project schedules are a key indicator in productivity. 72% of respondents indicated that prefab and modular construction process have a positive impact on the project schedules, with over 40% of those responding hinting and indicating it can reduce schedule time by four weeks or more with improved positive impacts on project schedules by using these processes.
8% of respondents believe that the processes reduce site safety whereas the majority of 55% believe prefab and modularization increase safety. The remaining 38% responded stating it was safety neutral.
It was believed that green building/waste reduction was not a major driver when the study was started. Once responders were asked about their views on green elements including wastage on site and material usage a different picture was painted. It emerged that 80% of respondents believe that these construction processes reduce site waste (40% believe with reduction of 10% or more) as well as 70% of respondents stating it reduces materials usage and 30% of those indicating reductions of 7% or more.
Cost and Budget
One of the key productivity metrics is project cost which is measured by project budget. 69% of users responded indicating that the use of prefabrication and modularization has positive impacts of the budgets as well as 60% of those stating reduced projects budgets of 5% or more.
The findings of the study have vast and different impacts for different user groups.
It is important that manufacturers producing prefabricated and modular building elements promote their green, waste efficient benefits that using their products has on waste reduction for construction project and sites.
As well as this they need/should create 3D BIM (Building Information Modelling) objects such that engineers and draughtman/architects can use in their 3D models. This in turn promotes THEIR products as well as increasing productivity in saving the modelers time. Time savings then equate to budget savings and productivity increases.
Due to being the main driver, as well as their primary responsibility in ensuring the structural integrity of construction projects, it is essential they evaluate the quality and also availability of using prefabrication and modularization processes/building elements within the design.
These could be from full modular construction, to simply using prefabricated panels, columns and beams for the superstructure. Additionally they can evaluate the benefits of when using such elements in an effective manner, this can in turn provide a bespoke design for the client as opposed to an of the shelf full modular “Lego block” design (Clients valuing modularization and prefabrication process as cheap options is a key restriction in using the processes).
As the initial connection with the client, the architect will have the most influence during the proposal meetings/ project set up and can influence key decisions through expert knowledge.
It is important that architects understand the key benefits in which using these processes offer (Prefabrication and modularization). Improved project schedule, reduced costs, reduced waste, increased site safety, improved installation quality). Once this is clearly understood it is important that they then educate clients in the same manner, wherever and whenever possible, potentially through email updates or workshops. They should also persuade the use of these processes to reduce costs and increase project productivity.
Clients and Building Owners:
As stated in the study, owner demand is the main driver I which dictated if architects will or will not use these process in their designs, and as thus clients/owners need to appreciate that the prefabrication and modularization construction process are not “cheap” but are instead now cost efficient in offering significant productivity gains within the project. Obviously only certain types of projects can use these processes (office space wouldn’t benefit true complete prefabrication/modularisation as future usage may need alterations to the interior and this isn’t easily modifiable in modular build due to load bearing structural walls. Instead clients need to be educate and wherever possible keep up to date on current techniques and appreciate their benefits as well as negatives on the required project deliverables.
General Contractors and Construction Managers:
Research has shown that prefabrication and modularization will reduce costs and usage of materials and installation as well as compressing the project schedule. These can therefore reduce budgets allowing contractors to be more competitive
For key specialist trades such as mechanical and electrical contracting in which modularization and prefabrication has become an integral part of their processes/business requirements. Because of this and the increased efficiencies, productivity gains and the projection forecasts showing increased usage of process on construction projects, it is important that these specialist contracts acquire the necessary experience and expert knowledge to stay ahead of the game and remain extremely competitive.
Market Activity and Opportunity – Sectors with Opportunity
There are many types of projects in which prefabrication and modularization are used and demonstrated especially in non-residential construction. There are 5 main sectors in which these processes are used;
– Higher Education
– Low-Rise Office
– Public Sector
These above sectors are additionally presenting strong opportunities within construction industries which indicated increased future usage in the future market.
Education/ Student Accommodation:
Similarly, to healthcare projects, school projects are extremely suited to prefabrication and modularization. Classroom requirements of set floor area as well as education accommodation of standard rooms and set requirements allow for modular design, prefabrication on existing sites and as such benefit from faster/ sped up construction schedules. Currently within the UK, education projects have received large sums of investment from the governments and are one of the largest construction sectors having received an investment of over £23bn in 2015 and an additional £320m in the spring budget 2017. (pbctoday, 2018)
(AMA RESEARCH, 2017)
Healthcare is especially suited to the modularization and prefabrication techniques. This is because the interior layouts allow for careful and efficient design of modularization. It is a sector that is very responsive to a high level to a shorter construction/project schedule (a benefit that prefabrication brings). The (AMA RESEARCH, 2017) “Healthcare Construction Market Report – UK 2017-2021” indicates that there is “around £5.7Bn worth of capital projects in the healthcare sector between now and 20202. And beyond. This includes nearly 600 individual health projects under almost 100 schemes”
(UK Construction Online, 2017)
Britain’s Great Exhibition – 1851. The Building called Crystal Palace. This is an early example of prefabrication.
During the industrial evolution Henry Cole (inventor of the Christmas card) convinced Prince Albert that an enterprise of showcase innovative inventions would be educational and inspirational to the masses whilst showing off the countries achievements. The Royal Commission was the appointed to make the exhibition a possibility but a problem arose, where would such a grand and extravagant event be had? A competition was launched (after no suitable place was found) to design a suitable venue. After 200 rejected designs were proposed, Joseph Paxton who was head gardener at Chatsworth House (Duke of Devonshire) and had already designed fountains, model village and built a conservatory, proposed a prefabricated solution. The solution was a structure of cast iron and glass that could be assembled in time for the grand opening.
The building structure called “Crystal Palace”, due to the use of 300,000 sheets of glass in a structure spanning the area of 3 football pitches and being 30 meters in height, was manufactured in the midlands and the prefabricated parts were then hoisted into position using cranes. The invention of the telegraph ensured constant communication between site and factories. So, with the aid of modern techniques, what would have taken substantially longer with ancient techniques, was constructed in just 22 weeks. Post exhibition the Crystal Palace structure was disassembled and re-erected in Sydenham, where it was able to stand until a fateful fire in 1936.
During and post World War 2, Prefabricated housing was extremely popular due to the need to provide mass accommodation for military personnel as well as the need to replace housing due to bombing and provided a cheap and speedy option.
The proliferation of the prefabricated housing came as a result of the “Housing (Temporary Accommodation) Act 194 and the Ministry of Works EFM (emergency factor made housing programme). This allowed a specification for housing types to be made, and allow private manufacturing and construction companies to Tender for the work.
Recent modern innovations within the past few decades have ensured that prefabrication and modular construction industry have been able to develop more process and materials to build more complex projects.
The Queen Mary 2 cruise liner – one of the largest and most expensive in the world – is an example of how well modular units are now accepted within industry. The ship owners chose to use modular passenger cabins to ensure build quality was identical and high standards were kept throughout (even the VIP suites utilize modular build techniques).
Prefabrication and modularization (although now becoming more recognized and resource-efficient) has not has the steady increase in usage over time that one would expect. It has fluctuated due to drastic need in war and economic booms as a solution to need for quick build housing and buildings in desperate times.
However, with the innovation of computer, BIM, modern quality materials, better production/ manufacturing facilities and checking standards, it has increased the capability and build quality in which prefabrication and modularization can achieve, and now offer productivity gains never seen before.
With the shortage of qualified experience site labor, designers and manufactures striving for leaner construction and process, this could possibly be another historical time for the use of prefabrication and modular construction, and the widespread adoption of these processes may begin. Only time will tell.
Case Study 1
London, Granada Travelodge
The hotel is a five Storey, 64 Bedroom building with integrated undercroft parking and using a Steel Frame modular construction technique known as “Prospex” which al
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