Task 1 – Superstructure Design and Materials UsedDescribe, images expected, and justify the selection of 2 MMC that could be used for the following types of structure:i. A detached 2-story residential house. Panellised Construction SystemsOne potential modern method of construction that would be advantageous to use for a small scale residential build would be panellised construction systems; Essentially this consists of panellised units that are manufactured in a factory and assembled on site to make up a three-dimensional structure. These panels are designed and built to take the form of either floor, walls, and roofs which can all be assembled on site to create a complete structural shell. They are often used in conjunction with other modern methods of construction and can also be used in existing structures to create new space and alter room layouts. There are two main types of panel’s – open wall and closed wall. Open wall panels arrive on site uncompleted, requiring additional fittings to be applied on site such as windows, doors, and insulation. Closed wall panels are much the same but are delivered to the site finished and ready to install. They can often come with all the internal wall finish complete so when they are installed they create a livable structure. There are many different materials used in the construction of the panels and depending upon the purpose of the panel within the building, this will change the materials generally used. Any load bearing panels are normally made from light gauge pre-galvanised steel and can be used for any component of the building. Structural panels, on the other hand, are generally made from concrete or composite materials such as oriented strand board which generally serve as the walls and roofs for buildings. Panellised construction is ideal for the construction of many buildings particularly those such as this one as it is suited to buildings with a varied wall, floor and roof sizes. There is a lot of saved using this MMC and can be framed quickly saving time and money. It also offers up a huge variety of readily available materials and faces for a client to choose from. Panels are usually made in controlled environments with precise specifications and often better quality materials that consequently provides a stronger more sturdy structure. There is also very little onsite waste as every panel is built to size off the site. Construction Techniques Hybrid Construction The hybrid method is essentially an integration of volumetric units and panellised systems and is often referred to as semi volumetric construction. This is ideal for residential properties and if done correctly reap the benefits of both methods of construction, but great care must be taken in ensuring the compatibility between the volumetric and panellised elements of the structure, particularly when using different contractors. Generally, when constructing a building using the hybrid method certain areas of the house that have a high number of services such as kitchens and bathrooms will be constructed as volumetric units, with the rest of the dwelling constructed with panels. This allows for the best of both worlds as volumetric will allow high value-added materials and fittings to be factory fitted whilst panellised construction will allow for greater flexibility in design. With this mix of construction methods work can be continued on-site whilst pods are being made off-site thus speeding the process up.An effective hybrid solution depends on the structures ability to make the most of each materials characteristics. Steel and timber are notably two very different building materials, by combining them, you can take advantage of the very best of each material, steel tensile strength and timbers strength to weight ratio, and overcome their limitations.ii. 5 ‘3 story office buildings’ each containing the capacity for 60 offices. Volumetric Construction Because of the repetitive nature of this build and its scale, volumetric construction would also be a very good option. Volumetric construction comprises of three-dimensional modular units constructed in controlled factory environments with quality control procedures in place, prior to transport to site. The units brought to the site can range in completeness, from the outer skeleton of the building to fully decked out units. The units are placed on top of the foundations using a verity of different techniques such as using a crane or landing platforms dependant on their size. These units can be stacked on top of each other to create different floors of the building dependant on the structural elements of the building. Volumetric units are usually constructed from lightweight materials which allow them to be transported easily. They are usually made from a combination of materials such as light gauge steel, timber, and concrete which can be of composite construction. Timber frame can often be the basis for the volumetric units as they can be constructed easily and installed on site with little in the way of foundation work. The external cladding of volumetric units can be done off-site with specialist sealing required on site. This type of construction is most effective when creating large-scale housing projects with multiple identical units required which is perfect for the proposed project. As a lot of the cladding work can be done off-site it leads the construction of an airtight building with much of the insulation installed in the factory which can lead to a high thermal performance unit.These units usually become economically viable when over one hundred units are required.Factory finished bathrooms and kitchens within an independent structure Pods were introduced into the construction market for hotels and student accommodation, although their use in apartments and housing is increasing. Pods are usually non-structural and are normally used within a loadbearing structure. The enclosure can be of a steel frame, timber frame, concrete or composite constructions. Substantial repetition is required to ensure pods are competitively costed with conventional methods. Left and right-handed versions of the same design constitute two different types of pod. Sub-assemblies and componentsDescribeSub-assemblies are large building components that are factory built and come in large variety of different forms to serve different purposes throughout the building, usual structural. Each component is built individually and when put together form the structural casing of the building. They can be used in conjunction with other sub-assemblies in modern structures or individually in pre-existing conventionally built structures. These can consist of pre-fabricated foundations were ground beams and other key components can be constructed off-site and assembled on site to form foundations.Roof cassettes: pre-fabricated panels designed specifically for pitched roofs. The panels are very stiff and are designed to leave the loft free of struts and props, allowing easy production of ‘room in the roof’ construction. Using roof cassettes allows the building to become watertight more quickly than with conventional trussed rafter or cut roof constructions. Pre-assembled roof structure: roofs assembled at ground level before constructing the shell of a dwelling. The roof can be craned into place as soon as the rest of the superstructure is in place, creating a weathertight structure more quickly than assembling the roof in situ. There are also health and safety benefits resulting from the workforce not undertaking all the work at height. Pre-fabricated dormers: factory made dormers can speed up the process of making the roof watertight.Roof cassettes are another form of subassembly and form parts of the roof. They are extremely ridged and are made so that the roof space is clear of all struts and props. They are pre-assembled sections of roof that already contain cladding and underside finishing. Pre-assembled roof structures are roofs that are constructed at ground level and craned into position. This method allows the building to come wind and watertight faster than constructing the roof on site.and is aimed at producing affordable social homes in the current economic climate. b) Evaluate the environmental performance of MMC and the methods used to construct the structures mentioned above. (350 words) • Limited pollution on site and to the surrounding area i.e. dust, noise, traffic• Less noise pollution• Pollution in the atmosphere Because modular sub-assemblies are completed in a factory, the construction site will require considerably fewer personnel than a traditional site would. Without the need for building material deliveries, noisy on-site machinery or large numbers of staff, noise pollution is reduced dramatically. Besides the environmental benefit, this also means sites are less likely to receive complaints and can be built both quicker and more harmoniously with the surrounding community – both of which are vital in busy urban areas.• Eco-friendly building materialsMany modular construction companies are adopting an environmental approach throughout all of their processes. This means incorporating eco-friendly building materials is now an innate part of the modular building process, lowering the environmental impact of prefabricated builds and reducing their overall waste consumption.The drastic reduction in wasted materials is primarily down to the fact that modular units are built in a highly controlled environment, instead of on-site at a traditional project location. Obsolete waste materials that would normally be sent to a landfill off-site can instead be recycled in other projects and for different purposes. Not only that, but the materials themselves are often eco-friendly from the get-go, with materials like FSC-approved timber and sustainably sourced steel regularly found in modular construction projects.• ReusabilityWith a recent surge of interest in building reusability and recyclability, modular builds can provide the flexible solution the buildings of the future need. Prefabricated sections are far easier to disassemble and relocate to different sites, thanks to their pre-assembled parts. If a building has become obsolete or disused, modular parts can be saved so that they don’t go to waste.If modular construction techniques became the norm, the requirement for fresh, raw materials for every new project would be substantially reduced. Where homes have become disused, whole rooms or even entire floors could be lifted out for use in other projects. In the UK, where we need to build an estimated 300,000 homes each year to help solve the housing crisis, this could be a huge asset. The innate flexibility of prefabricated homes could go a long way to support construction companies in their efforts to meet government targets, while also dramatically reducing the industry’s burden on the environment.• Precision• Factory conditions quality control • Time savings due to less production techniques, Reduced energy consumptionBecause modular construction companies operate in a controlled environment, the energy poured into the assembly process is only a fraction of that which would be used on-site. The majority of parts built in this way are built in a system similar to an assembly line, which reduces the time spent on building individual parts and removes the need to assemble individual materials on-site.This efficiency is part of the reason modular manufacturing requires substantially less energy than other traditional assembly techniques. In modular builds, everything from the bathroom wall tiles to the drainage systems are integrated from the start – reducing assembly time, minimising wasted material and providing a consistent quality level throughout.• QualityThis has not only increased the speed of on-sight erection for the completed units but has also resulted in improved performance, This is due to the fact that a high level of quality control can be maintained in workshop conditions before the completed components are taken to site for assembly. Using prefabricated components improves the quality of the finished product and also speeds up work on site. However, the success of prefabrication within the construction process depends on the followingThe quality achievable with factory prefabrication is generally higher than can be achieved on site. This particularly applies to welding and hot trades such as pipework and mechanical services. Back-to-back toilet and basin units mounted on steel framework are commonplace. Even mini plant rooms lend themselves to prefabrication. This can save a lot of complex site work in confined spaces.• Reduction in on-site production• Ability to construct superstructure in factory while the substructure work is completed on siteOff-site fabrication, a recent development by UK manufactures, is, for example, where a timber-framed house can be assembled off-site, delivered by lorries and then site assembled using a crane. The only additional elements needed are the cladding external finish, which can be in a brick skin or a timber cladded prouctm and rhte roof tiles. This type of constructon is very thermally efficient, saves time and energy, uses renewable timber products and has relatively low carbon emissions in maunfactre. Off site fabrication of structural elements of commercial and domestic construction is the new approach to the production of houses and offices. Modules that simply bolt together are fast and efficient methods of producing a structure that is factory produced with minimal resulting wastage. This method is very efficientEnergy efficient and air tightness Task 2 (Infrastructure) 300 wordsBriefly describe the types of infrastructure needed to support the structures in Task 1 On of the main benefits of modern methods of construction is the lack of infrastructure needed in the construction process. Unlike traditional methods, there is little storage needed to harbor materials as once construction of the superstructure commences it’s a very short time before it finishes. Total construction plant required is also vastly reduced however considerations must be made into the accessibility to the site for vehicles and plant. Cranes, for example, require a minimum amount of height and so cables and pylons should be mapped and noted. Vehicles used to trapthe modular components usually take up a large amount of space on the road and mmc may not be practical in areas in the countryside with small lanes, temporary roads may also need to be incorporated into the site and made wider to compensate for the size.Scaffolding must be erected by a qualified and competent individual and should not be temprered with by any unqualified individual. All the appropriate hand tools to secure the superstructures to the foundations plus attach fittings to any incomplete unit. General health and safety regulations as always must be introduced and enforced such as the correct application of PPE and regularly adapted risk assessments for all the equipment and activities taking place on the site. All potential safety hazards should be made known via clearly visible signs placed around the site. Health and welfare is another important form of infrastructure which will be needed for the above substructures, as good facilities can positively benefit health and well-being of workers on site. Construction workers need adequate toilet and washing facilities, a place to warm up and eat their food and somewhere to store clothing. Efforts should be made to add basic security to the site when inactive, such as security lights and metal fencing. This is done to prevent intruders from taking the power tools and other equipment. It is also done to prevent residents of the building from injuring themselves on the building site.