Prefabricated Housing

DISSERTATION REPORT

PREFABRICATED HOUSING

SUBMITTED BY:

GUIDED BY: PROF SOMA A MISHRA

RAHIL KHAN B. ARCH. VIII SEM. SOA IPS ACADEMY

DECLARATION

I hereby declare that the Dissertation Project – prefabricated housing submitted by me in partial fulfillment for the award of degree of Bachelor of Architecture of Rajiv Gandhi proudyogiki vishwa vidyalaya, Bhopal, India is a record of my work. The matter embodied in this project has submitted for the award of any other degree or diploma.

Rahil Khan

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CERTIFICATE

This is to certify that the above declaration of Rahil Khan is true to the best of my knowledge and that he has worked for one semester for preparing this Dissertation Project.

RECOMMENDED

PROF. B.V YADAM

ACCEPTED

AR. B. V. YADAM

Head of the Department School of Architecture, IPS Academy, Indore

Date: Place:

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INDEX

NO.

CONTENTS

COMMENTS

1.1

INTRODUCTION

1.2

HISTORY

1.3

SELECTION CRITERIA

1.4

EXPENSE / BENEFITS

1.5

BUILDING STRENGTH

1.6

ASSEMBLEY TIME

1.7

MARKET ACCEPTANCE

1.8

LIMITATION

2.1

PREFABRICATED BUILDING

2.2

TYPES OF PREFAB HOUSING

SIGN

1. MANUFACTURED HOUSING 2. MOBILE HOME 3. MODULAR BUILDING 4. MODULAR HOME 5. PORTABLE HOUSING 6. PANELIZED HOMES

3.1

INDIAN CONTRIBUTION IN PREFABRICATED HOUSING

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4.1

MATERIALS

5.1

ANALYSS

5.2

CONCLUSION

6.0

BIBLIOGRAPHY

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1.1

INTRODUCTION

Prefabrication is the practice of assembling components of a structure in a factory or other manufacturing site, and transporting complete assemblies or sub-assemblies to the construction site where the structure is to be located. The term is used to distinguish this process from the more conventional construction practice of transporting the basic materials to the construction site where all assembly is carried out. The term prefabrication also applies to the manufacturing of things other than structures at a fixed site. It is frequently used when fabrication of a section of a machine or any movable structure is shifted from the main manufacturing site to another location, and the section is supplied assembled and ready to fit. It is not generally used to refer to electrical or electronic components of a machine, or mechanical parts such as pumps, gearboxes and compressors which are usually supplied as separate items, but to sections of the body of the machine which in the past were fabricated with the whole machine. Prefabricated parts of the body of the machine may be called 'sub-assemblies' to distinguish them from the other components

THE PROCESS AND THEORY OF PREFABRICATION The conventional method of building a house is to transport bricks, timber, cement, sand, steel and construction aggregate, etc to the site, and to construct the house on site from these materials. In prefabricated construction, only the foundations are constructed in this way, while sections of walls, floors and roof are prefabricated (assembled) in a factory (possibly with window and door frames included), transported to the site, lifted into place by a crane and bolted together.

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HISTORY Prefabrication has been used since ancient times. For example, it is claimed that the world's oldest known engineered roadway, the Sweet Track constructed in England around 3800 BC, employed prefabricated timber sections brought to the site rather than assembled on-site. Ancient Sri Lanka used prefabricated in building monastic structures, where some sections were prepared separately and then fitted together. The method was widely used in the construction of prefabricated housing in the 20th century, such as in the United Kingdom to replace houses bombed during World War II. Assembling sections in factories saved time on-site and reduced cost. However the quality was low, and when such prefabricated housing was left in use for longer than its designed life, it acquired a certain stigma. The Crystal Palace, erected in London in 1851, was a highly visible example of iron and glass prefabricated construction; it was followed on a smaller scale by Oxford Rewley Road railway station.

SELECTION CRITERIA 1. it should be quick to erect and easy to install 2. it should be light in weight , adaptable and portable 3. to an extent be possible to be built up with locally available material 4. it should posses good environmental control and should be able to cope up with the weather and deal with the ground conditions 5. it should require minimum maintenance. 6. it should be resistant to earth quake, wind storm, rain, and extreme heat or cold. 7. the assembly should be simple so that it could be set up by local people and req. min labour 8. if possible it must be cost effective.

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EXPENSE / BENEFIT Modular buildings are very affordable because of the factory construction of these buildings. They are a very cost effective compared to conventional construction. These units are typically constructed in an enclosed facility therefore weather is not a factor in the construction time line. Material delivery fees are also out of the equation because an ample amount of material will always be available at the facility, as opposed to being delivered in limited quantities to the job site, nearly eliminating construction delays, and theft of building materials from the site.

STRUCTURAL STRENGTH According to manufacturers, modular homes are generally designed to be initially stronger than traditional homes by, for example, replacing nails with screws and adding glue to joints. This is supposed to help the modules maintain their structural integrity as they are transported on trucks to the construction site. Despite manufacturer claims that the modular home is initially built to be stronger than a traditional home, it is difficult to predict the final building strength since it needs to endure transportation stresses that traditional homes never experience.

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ASSEMBLY TIME The modules that will combine to form the house are assembled off-site in a factory. These modules can take one to three months to be constructed but often take as little as 10 days actually to construct when they are first started. Then they are transported to the building site where a crane is brought in to assemble the modules together. The placement of the modules together generally takes several hours or days. Once assembled, modular buildings are essentially indistinguishable from typical sitebuilt homes. While mobile manufactured buildings often decrease in value over time, a well-built modular should have the same longevity as its site-built counterpart, increasing in value over time.

CONSTRUCTION SURFACES Modular buildings can be assembled on top of multiple foundation surfaces, such as a crawl space, stilts (for areas that are prone to flooding), full basements or std. slab on grade. They can also be built to multi-story heights. Motels and other multi-family structures have been built using modular construction techniques. The height that a modular structure can be built to depends on jurisdiction but a number of countries, especially in Asia, allow them to be built to 24 floors and possibly even more. Exterior wall surfaces can be finalized in the plant production process or in the case of brick/stone veneers field applications may be the builder’s choice. Roof systems also can be apart of - separate from - applied in the field after the basic installation is completed.

MARKET ACCEPTANCE Some home buyers and some lending institutions resist consideration of modular homes as equivalent in value to site-built homes. While the homes themselves may be of equivalent quality, entrenched zoning regulations and psychological marketplace factors may create hurdles for buyers or builders of modular homes and should be considered as part of the decision-making process when exploring this type of home as a living and/or investment option. In the other countries like UK & Australia modular homes have become quite accepted in regional areas however are not commonly built 10

in major cities. Some modular building manufacturers have begun to refer to modular buildings as “off-site construction” to combat the negative image of modular which is due to portables or trailer stereotypes. Recent innovations allow modular buildings to be indistinguishable from site built structures. LIMITATIONS The study will be dealing with the various forms of prefab houses, It will not cover the construction details; the report will cover its progress.

2.1

PREFABRICATED BUILDING

Prefabricated building is a type of building that consists of several factory-built components or units that are assembled on-site to complete the unit Prefabricated homes often referred to as prefab homes, are dwellings manufactured off-site in advance, usually in standard sections that can be easily shipped and assembled. Some current prefab home designs include architectural details inspired by postmodernism or futurist architecture. Prefab homes have not been particularly marketable; possible reasons for this include: 

Homes are not currently produced cost-effectively enough for current demand.



Homes are not considered a realistic housing solution by the average consumer.

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The consumer is either not familiar with the concept, or does not desire it.

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Social stigma that exists because of low quality mass produced designs used in the past.

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Difficulties obtaining finance due to stricter guidelines being used by lenders to assess prefab home loans.

Modern architects are experimenting more often with prefabrication as a means to deliver welldesigned and mass-produced modern homes. Modern architecture forgoes referential decoration and instead features clean lines and open floor plans. Because of this, many feel modern architecture is better suited to benefit from prefabrication.

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TYPES OF PREFAB HOUSING

1. Manufactured housing 2. Mobile home 3. Modular building 4. Modular home 5. Portable housing 6. Panelized homes

MANUFACTURED HOUSING Manufactured housing (also known as prefabricated housing) is a type of housing unit that is largely assembled in factories and then transported to sites of use. The original focus of this form of housing was its mobility. Units were initially marketed primarily to people whose lifestyle required mobility. However, these homes began to be marketed primarily as an inexpensive form of housing designed to be set up and left in a location for long periods of time, or even permanently installed with a masonry foundation. Previously, units had been eight feet or less in width, but in 1956, the 10foot (3.0 m) wide home was introduced. This helped solidify the line between mobile and house 12

travel trailers, since the smaller units could be moved simply with an automobile, but the larger, wider units required the services of a professional trucking company.

MOBILE HOME Mobile homes or static caravans are prefabricated homes built in factories; They are usually transported by tractor-trailers over public roads to sites which are often in rural areas or high-density developments. In some countries they are used for temporary accommodation on campsites. While these houses are usually placed in one location and left there permanently, they do retain the ability to be moved as this is a requirement in many areas. Behind the cosmetic work fitted at installation to hide the base, there are strong trailer frames, axles, wheels and tow-hitches. The two major sizes are single- wides and double- wides. Single-wides are eighteen feet or less in width and 90 feet (27 m) or less in length and can be towed to their site as a single unit. Double-wides are twenty feet or more wide and are 90 feet (27 m) in length or less and are towed to their site in two separate units, which are then joined together. Triple-wides and even 13

homes with four, five, or more units are also built, although not as commonly. While site-built homes are rarely moved. Modular homes are homes that are created in sections, and then transported to the home site for construction and installation. These are typically installed and treated like a regular house, for financing, appraisal and construction purposes, and are usually the most expensive of the three. Although the sections of the house are prefabricated, the sections, or modules, are put together at the construction much like a typical home. Manufactured and mobile houses are rated as personal property and depreciate over time. - Manufactured homes refer to homes that are built onto steel beams, and are transported in complete sections to the home site, where they are assembled. - Mobile homes are, quite simply, mobile homes; that is, homes built on wheels that are able to be moved from place to place. Mobile homes and manufactured homes can be placed in mobile home parks, and manufactured homes can also be placed on private land, providing the land is appropriately zoned for manufactured homes.

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MODULAR BUILDINGS Modular buildings are sectional prefabricated buildings that are manufactured in a plant, and delivered to the customer in one or more complete modular sections. Modular buildings are considerably different from mobile homes. Modular buildings have a wide variety of uses. They will either be used for long-term temporary or permanent facilities. Such uses include construction camps, schools and classrooms, civilian and military housing needs, and industrial facilities. Modular buildings are a perfect solution in remote and rural areas where conventional construction may not be reasonable or even possible.

MODULAR HOME Modular homes are houses that are divided into multiple modules or sections which are manufactured in a remote facility and then delivered to their intended site of use. The modules are assembled into a single residential building using either a crane or trucks. Steel or wood framing are common options for building a modular ho Such dwellings are often priced lower than their site-built counterparts and are typically more cost-effective to builders and consumers. These new homes can be constructed in less time than it takes to build a home "on-site". Manufacturers cite the following reasons for the typically lower cost/price of these dwellings: 

Indoor construction. Assembly is independent of weather which increases work efficiency and avoids damaged building material.



Favorable pricing from suppliers. Large-scale manufacturers can effectively bargain with suppliers for discounts on materials.



Ability to service remote locations. Particularly in countries such as Australia there can be much higher costs to build a site-built house in a remote area or an area experiencing a construction boom such as mining towns. Modular homes can be built in major towns and sold to regional areas.



Low waste. With the same plans being constantly built, the manufacturer has records of exactly what quantities of materials are needed for a given job. While waste from a site-built dwelling may typically fill several large dumpsters, waste from a modular dwelling generates much less waste. 15

MODULAR HOMES VS. MOBILE HOMES Differences include the building codes that govern the construction, types of material used and how they are appraised by banks for lending purposes. Mobile home (manufactured homes) is generally considered lesser quality. The materials are the same as site constructed homes. Wood frame floors, walls and roof are the most typical. Some modular even included brick or stone exteriors, granite counters and steeply pitched roofs. All modular are designed to sit on a perimeter foundation or basement. Mobile homes are constructed with a steel chassis that is integral to the integrity of the floor system. Lending institutions and appraisers consider a modular home the same as they consider a site built home, with the same life expectancy and value. Mobile homes often require special lenders. Most companies have standard plans. However, all modular buildings can be custom built to a client’s specification. Today's designs include multi-story units, multi-family units and entire apartment complexes. The negative stereotype commonly associated with mobile homes and has prompted some manufacturers to start using the term Off-Site Construction.

PORTABLE BUILDING A portable building, or demountable building, is a building designed and built to be movable rather than permanently located. A common modern design is sometimes called a modular building, but portable buildings can be different in that they are more often used temporarily and taken away later. Portable buildings (e.g. yurts) have been used since prehistoric times. The most familiar modern type of portable buildings are designed so that one can be carried to or from site on a large lorry and slung on and off by a crane. The first known portable building or "knock-down" building was developed by US firm Porta-Kamp in 1955, The first portable building under the trade name Portakabin was built in 1961 in England.

PANELIZED HOMES Sometimes referred to as a prefab home. Panelized construction involves the building of individual walls, or wall sections in a factory. Panelized home producers are the biggest and most diverse segment of the factory-built housing industry. Panelized homes are different compared to modular homes and manufactured homes. There are some similarities, but panelized homes utilize “Components” or “wall units” that are pre-built in a controlled environment, (factory). The main advantage of panelized homes over stick-built homes is - shorter build time with lower labor costs 16

Panelized Kit Homes are an open panel system where wall panels are assembled in a factory environment, using state of the art equipment. Essentially what is included in our kit homes is the "shell" of the house. The window and door openings are pre-framed, and the exterior sheathing is already applied. For complete details and materials specifications of our kit homes , visit our What's Included page. There are many benefits of our panelized kit homes vs. conventional construction: 

Cost Savings on Materials & Labor

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High Quality Materials

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Simplified Building Process

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100% financing

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True owner builder program

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Less waste and a cleaner job site When you are comparing various alternative construction methods, there's one important thing to keep in mind:

Panelized Kit Homes are viewed as stick built homes by building inspectors, appraisers, and lenders. Once your home is complete, no one will ever be able to tell that it was a kit house! 17

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PREFABRICATED BUILDING MANUFACTURERS Hindustan Prefab Limited (A Government of India Enterprise) an ISO 9001: 2000 certified a company was incorporated in 1953. In the 50 years of its existence, HPL has built a wide spectrum of civil engineering structures using both conventional in-situ as well as prefab techniques and has also supplied components for the building industry & the national railways. It pioneered the production of pre-stressed concrete railway sleepers, which replaced wooden sleepers in Indian Railways. Hindustan Prefab Limited is functioning under Ministry of Housing and Urban Poverty Alleviation. As a construction company, HPL propagates the use of various techniques in housing as mentioned below. 1) Large panel fully prefab system. 2) Composite roofing system using precast beams and other eliments. 3) Partial prefab system using cast-in-site walls and precast roofs. 4) Totally cast-in-situ system using small precast elements. Prefabricated Building Manufacturers make and supply modular structures. Lots of them have manufacturing facilities at one or more locations and supply their products worldwide, while some cater only to their local area. Prefabricated Building Manufacturers can specialize in the type of buildings they make. For instance, they might be providing their buildings only for residential use, or industrial purposes. Some manufacturers fabricate just steel buildings, while other might supply wood and fiberglass also. On the other hand, some of them would be experts in solar geothermal homes or floor-to-ceiling glass buildings. By and large, all Prefabricated Building Manufacturers would require your specifications before giving a quote. Some might offer ready-made, predesigned buildings also, if they are close to your requirements. Mostly they undertake shipping and installation of the Prefabricated Buildings. If some assistance in design is required, they might charge separately for it. Or you might get in touch with Prefabricated Building consultants for a professional opinion.

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In this era of high competition, it is essential to get hold of the right manufacturer who would give quality materials and good service at a reasonable cost. Check out the warranty details and installation support that they are committing. Even the building material specifications should meet the local area’s building code. Do refer to their existing customers to find out the level of satisfaction. A reputable name might be a little costlier but should prove to be more reliable. On the other hand, if you need the Prefabricated Building only for some short and temporary purpose, you can go in for a local supplier as well.

3.1

INDIAN CONTRIBUTION IN PREFABRICATED HOUSING

If two decades ago someone had told you that one day it would be possible to have instant houses like instant coffee or instant noodles you would have thought that person was crazy. The best we could think in terms of portable homes or instant homes was of tents or caravans or trailer homes. But now in this world we also have instant homes.

The portable houses can vary in size according to your requirement ranging from 8x8 feet, 8x12 feet, 12x16 feet and 16x32 feet. And they are really catching on in Delhi as people can extend their houses without having to go through the hassle of getting permission from the authorities concerned as they are not permanent structures and can be installed and dismantled easily at the site. The dimensions of walls, roof, door and window can be altered easily according to design specifications. They have a variety of designs suitable for different climatic conditions, wind speeds and seismic zones in India.

The roof and walls of these cabins are insulated using thermocole /-mineral wool. They are fully insulated externally and air-conditioned internally (optional). these pre-fabricated structures are insulated, the cost of heating and cooling them is almost 70 per cent lower compared to conventional buildings. They require minimal maintenance and repair. Their costs are reasonable and the best is that they are environment-friendly. They have the ability to withstand harsh weather conditions. They can also be designed according to your specifications in next to no time. You can have an entire home that is prefabricated.

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PREFABRICATED WOOD HOUSES IN INDIA Lockwood International, a leading New Zealand-based wood construction company, has launched its first prefabricated wood houses in India aimed at the luxury realty segment in the country. The company showcased its first model house at the Classic Golf Resort in Gurgaon, on the outskirts of the national capital, on Tuesday. MacDonald Sarin, a realty asset management company in Gurgaon, will market the houses in India. "Just like modular kitchens and bathrooms, prefabricated wood houses are made by fixing predesigned wooden building blocks," The houses cost between Rs 6,000 and Rs 7,000 per sq ft. "The wooden building blocks are fixed by a special lock-wood technology without use of nails or cement or steel in just two months. So people do not have to wait for a year or two to enjoy their dream house," These houses are very popular in European countries. The Indian Forest Research Institute has tested pinewood for its suitability in Indian conditions, adding these structures are also resistant to earthquakes and termite attacks. New Zealand's Agriculture, Forestry and Fisheries Minister Jim Anderton launched a prototype of the house. He is in India to offer sustainable timber resources to the booming Indian housing and construction industry. "As India is now protecting its native forest and needs to import the timber to meet growing demand for construction and other industry. "The New Zealand wood industry currently generates $3.1 billion in exports to India. We are the fifth largest export market for wood products."

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INDIAN CONTRIBUTION IN MAKING COST-EFFECTIVE BUILDING MATERIALS The in-house research and development (R&D) unit of the Hyderabad Industries Limited (HIL) has developed an innovative prefabricated building material, called the `Aerocon Sandwich Panel', using fly ash in combination with cement and vermiculite, a mica-like material that imparts fire-resistant properties to the material. The new prefab product from HIL is the latest in a line of products manufactured by the company, and used in building and construction activity, such as plywood, gypsum board, cement-bonded particle board, resin-bonded particle board, and so on. The light-weight, fire-resistant Aerocon panel is made up of two fiber-reinforced cement sheets, on either side of a light concrete core composed of Portland cement, binders, silica and other materials in certain proportions. It has an interlocking sandwich design, with a tongue and groove joining system, to make it compact and sound. The prefab blocks are designed for utility in offices, penthouses, partition walls in commercial establishments, and for cabins and booths. Because of their low weight and flexibility, the aerocon panels can be transported easily and utilized in the cons truction of temporary shelters in cyclone- or earthquake-affected areas, or even by the armed forces in remote areas.

TILES FROM FLY ASH In another development initiative, a Mumbai-based company, H&R Johnson's research group has fabricated prototype tiles using the waste fly ash generated from a thermal power plant. The researchers obtained the waste material from the Tata Electric Company, Trombay, from which they made briquettes. They found that the composition of the fly ash was a virtual replica of clay which, in turn, is ideally suited to the manufacture of tile. In the manufacture of fly ash-based tiles, this means two advantages. First, the use of fly ash can cut the requirement of natural quartz in the body of the wall-tiles. And second, since the fly ash is freely available, the overall cost of the final product is less. 22

MATERIALS

BAMBOO SHUTTERING, BAMBOO FILM FACED PLYWOOD, BAMBOO PLYWOOD - BAMBOO SHUTTERING bamboo plywood, bamboo shuttering, bamboo film faced plywood; ; [bamboo plywood, bamboo shuttering, bamboo film faced plywood.

STEEL SPACE FRAME - SF

CXIC is the leading company for space frame structure in China. The Grade A enterprise of steel structure and space frame works-the qualification Certificate has been awarded by China [space frame, steel structure, pre engineered structure]

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POLYCARBONATE (PC) SOFTLITE SHEET - PC SOFTLITE SHEET

Polycarbonate corrugate sheet features a high combination of unique qualities ? high impact strength, light transmission, flexibility, light weight and excellent performance under wide temperature range. [Polycarbonate Hollow profile sheet, Polycarbonate sheet, Polycarbonate Solid sheet, Polycarbonate corrugated sheet, PC Soft lite, PC sheet

PARTITIONS AND FALSE CEILING partitions & false ceiling by using UPVC multi-cavity 50 x 50 2.5mm frame suitably reinforced and welded in corners and paneled by 20mm x 116mm x 1.2mm panels with EPDM Gasket & Glass bead with provision of door shutter partition glass, windows (turn/Sliding) and roofing of 20 x 116 x 1.2mm panels with truces, supports, etc.

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PLASTIC AIR REGISTER Features: 1)

For floor use and heating and cooling applications 2) Solid ABS construction 3) Integral

multi-shutter damper with easy-to-use damper handle 4) Brown color 5) Any color available (2 weeks more) 6) Available in 2 x 10, 4 x 10

SANDWICH PANEL LINE Features: It can take the EPS cores and thickness is 50 - 250mm 2) It is automatic machine

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HANDSCRAPED OAK DARK FLOORING Features:

1) Tree origin: northern China, Russia 2) Color: pale yellow 3) Tough texture, fine structure 4) High strength, good resistance to abrasion and corrosion 5) Exceptional stability, good anti-shocking performance 6) Flooring.

GRANITE KITCHEN TOPS Features: 1) Types: countertops, kitchen tops, bar tops, half island and island in different designs, colors, and sizes are available, such as 96 x 26 , 110 x 26 , 100 x 36.5 , 84 x 36 , 72 x 48

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CLEAR TEMPERED GLASS (FLAT) The quantity, size, thickness, color, processing requirements, such as drilling holes, edging (such as flat edge polished, not polished, C-edge polished, minimum edge), corner processing, silk screen print.

ALUMINUM COMPOSITE PANELS Features:

1) Weather resistance 2) Fireproof 3) Even coating 4) Easy maintenance 5) Excellent torsion strength Specifications: 1) Standard size: 1,220 x 2,440mm 2) Max. Width: 1,600mm 3) Max. Length: 6,000mm 4) Surface: PVDF, polyester. 27

MESH FILM FACED PLYWOOD Specifications: 1) Size: 1250 x 2500mm, 4 x 8' 2) Thickness: 18, 21mm

FIBERGLASS WIRE NETTING Vinyl coated fiberglass yarn insect screen (fiberglass screen) Coated yarn insect screen is made of fiberglass under the process of plastic-coating, plain weaving and high temperature-fixing. Vinyl coated fiberglass insect screen is well ventilate.

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MDF BOARD (MEDIUM DENSITY FIBER BOARDS) Features: 1) Dimensions: 4 x 8' (1,220 x 2,440mm) 2) Thickness: 2.5 - 3mm, 3.5 - 4.6mm, 9mm, 12mm, 15mm, 16mm, 17mm, 18mm, 25mm

ALUMINUM LATH CEILING Features: 1) Standard width: 50mm, 75mm, 100mm, 150mm, 175mm, 200mm and 250mm 2) Materials: a) Surface: improved PET, which has more advantages than common PET, including bacterium resistance. This surface make our ceilings very ideal for living...

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5.2

ANALYSIS

ADVANTAGES OF PREFABRICATION Self-supporting ready-made components are used, so the need for formwork, shuttering and scaffolding is greatly reduced. 1. Construction time is reduced and buildings are completed sooner, allowing an earlier return of 2. the capital invested. 3. On-site construction and congestion is minimized. 4. Quality control can be easier in a factory assembly line setting than a construction site setting. 5.

Prefabrication can be located where skilled labour is more readily available and costs of labour, power, materials, space and overheads are lower.

6. Time spent in bad weather or hazardous environments at the construction site is minimized. 7. Less waste may be generated and in a factory setting it may be easier to recycle it back into the manufacturing process, for instance it is less costly to recycle scrap metal generated in a metal fabrication shop than on the construction site. 8. Molds can be used several times.

DISADVANTAGES OF PREFABRICATION 1. Careful handling of prefabricated components such as concrete panels or steel and glass panels is required. 2. Attention has to be paid to the strength and corrosion-resistance of the joining of prefabricated sections to avoid failure of the joint. 3. Similarly, leaks can form at joints in prefabricated components. 4. Transportation costs may be higher for voluminous prefabricated sections than for the materials of which they are made, which can often be packed more efficiently. 5. Large prefabricated sections require heavy-duty cranes and precision measurement and handling to place in position. 30

6.

BIBLIOGRAPHY

e-BOOKS – Prefab: Bryan Burkhart, Allison Arieff:

The Modular Home: Andrew Gianino:

Inside outside

INTERNET – www.citehr.com www.google.com www.msn.com www.wikipedia.com www.indiahousing.com www.kellysearch.co.in www.new-building-system.com

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