So called “ Modern Methods ” of building have been put frontward as a solution for work outing the job of supplying low-cost lodging in sustainable communities for the UK.
In a study for senior directors of a major lodging development company propose and warrant modern methods of building to replace traditional building production techniques.
There is turning concern in UK that lodging is going more and more expensive. There are a figure of concerns among experts that the building industry as a whole is underachieving. This has been peculiarly emphasised in the Egan study ( Egan, 1998 ) , where it is besides mentioned that the initial chances for betterments in house edifice exists in the societal lodging sector. Another concern that is really much in the calcium hydroxide visible radiation late is sustainability issues. The European community and UK have agreed of environmental and energy marks that are really ambitious.
Houses in UK have traditionally been built in traditional stuffs such as brick and concrete. The building stuff and building techniques have non changed much in centuries, despite the high degree of building know-how that exists in UK. Most of the modern building techniques are use for high-profile prestigiousness edifices and commercial edifices. The lodging sector does non look to hold benefited from the modern methods available.
This study aims at fanning-out the assorted modern methods of building that can profit the lodging sector in many ways. Most of these modern methods are already used rather successfully in countries other than lodging. The mark will be to turn out how, by agencies of modern building techniques, low-cost and sustainable lodging can be developed.
Sustainability by and large means sustained ability. It means being able for longer. It means being able to profit from resources for longer, without jeopardizing the depletion of the resources. Sustainable building is an attack to building that makes optimum usage of resources throughout the lifetime of a edifice. This includes the resources utilised for the building of the edifice, its operation and care, and its eventual disposal. Resources here associate to beginnings of stuff, energy, infinite and money. Those are the basic demands for a edifice.
It besides makes economic sense to utilize as less resources as possible. So, accomplishing sustainability should non be excess to the client, although it may be excess ab initio to construct the edifice. A typical edifice uses many times more resources during its lifetime than during its building. So globally, it will be in the client ‘s involvement to travel for sustainable methods.
Sustainable building ( Stern and Knapp, 1993 ) could besides be distinguishable as those edifices that have minimal inauspicious impacts on the built and natural environment, in footings of the edifices themselves, their immediate milieus and the broader regional and planetary scene. The rational usage of natural resources and appropriate direction of the edifice stock will lend to salvaging scarce resources, cut downing energy ingestion ( energy preservation ) , and bettering environmental quality.
A general scheme for environmental witting design ( Boontra, 1997 ) consists of three chief stairss:
- Reduce the stuff demand– Any client, investor or governmental organic structure should thoroughly measure the demand for a new edifice activity by look intoing the possibilities of reuse and restituting bing edifices. Interior designers should plan a edifice every bit expeditiously as possible by understating the sum of resources needed. This can be done by optimizing both the floor program and building.
- Application of renewable and recycled beginnings– By application of renewable and recycled beginnings the life rhythm of edifice stuffs can be closed. Interior designers should besides let for future recycling. Planing a edifice for leveling and non for destruction is one attack.
- Choice stuffs with the lowest environmental impact– The environmental impact of stuffs is caused during a edifice ‘s complete life-time. Typical environmental issues are natural stuffs, corporal energy, emanations, hinderance, waste, recycling, fix, life-time.
Throughout the study, it will be demonstrated that the modern methods proposed will react positively to the above environmental standards.
Buildings account for the largest proportion of energy ingestion in most western societies. In UK for illustration, ( Nicholls, 2002 ) energy ingestion in edifices account for 45 % of the entire UK energy ingestion. Energy is widely produced by firing fossil fuel such as gasoline and coal. It is besides used by atomic fission of Uranium. Both procedures are really harmful to the environment.
Why are Modern Methods Important for a Major Housing Developer?
Previously, sustainability was associated with environmental issues. However, in recent old ages it has been recognised that one can non continue environment at the disbursal of socio-economic advancement. Sustainability is now being redefined in many circles as a balance of:
- Economic– stable economic growing and employment
- Environment– protection of environment and prudent usage of natural resources
- Social– societal advancement for everyone
For these grounds, it is non merely of import that building is clean and energy efficient, but it is besides of import to see other factors such as the impact of the building on its immediate vicinity and the society in general. The cost of building has a direct impact on the cost of the lodging. It is of import to do lodging economically feasible and low-cost without cutting down on our border.
Legal Developments in Sustainability
There have been several recent legal developments in the country of sustainability that will hold a definite future impact on our operations on the UK lodging market. Most of these legal developments follow the 1997 Kyoto Earth Summit and are in line with the current authorities ‘s emanation and energy marks. The chief developments are:
- UK Sustainable Construction Strategy 2000
- UK Energy White Paper 2003
- Sustainable Building Task Group 2003
Some of the impacts of these legal developments are already being felt. For case, Part E and Part L of Building Regulations are already being revised and will be more demanding in footings of thermal and acoustic public presentation of edifices. There are several assessment methods being developed to mensurate quantify and rate the public presentation of a edifice in footings of how sustainable it is, and many of these step will be taken into history for be aftering permission intents. One of them is the BREEAM evaluation, developed by the Building Research Establishment. The BREEAM is an environmental appraisal for offices, industrial and retail edifices. It consists of a checklist with tonss for energy usage, conveyance, H2O usage, pollution, stuffs, land usage etc. It has four evaluations: base on balls, good, really good and first-class.
Another such appraisal method is the Eco-Homes, which is applied to lodging sector merely and hence more relevant to us. The Sustainable Building Task Group 2003 has put frontward a recommendation for a Code of Sustainable Building, which is based on the BREEAM evaluation but is simpler. The Code has the full backup of the authorities and is presently mandatory for societal lodging sector. Although it is non mandatory for our market yet, it is more than probably that it will go so in a close hereafter.
Another appraisal method that may go of import in the hereafter is the WRAP, which measures the recycle content of a edifice. As for now, any edifice must hold a lower limit of 10 % of recycle content. Most edifices will easy run into that demand, even those built by the traditional methods. However, it is the purpose of the governments to steadily increase that 10 % demand in the coming old ages and it will go progressively hard to run into by traditional physiques. WRAP is critical for be aftering permission and it is in the long term involvement of the company that we start utilizing methods that will present higher recycle contents in our lodging developments.
Health and Safety
Health and Safety is going more and more of import for the authorities and besides for private clients. The approaching CDM ordinances 2006 will hold major alterations that put a batch more duty on the clients. Consequently, it can be expected that client will be seting wellness and safety high in their docket and will take their developers and contractors with that in head.
Besides the HSE is being more and more demanding about the criterion of wellness and safety and work and cheques are done on a regular footing on sites across UK. It is hence of import to be proactive and take a holistic attack towards wellness and safety. Alternatively of merely providing more boots and helmets to site, it will be wiser to follow methods that are inherently safer.
Typically, a lodging development will either dwell of some blocks of flats with parking infinite or a series of 2 to 3 floor houses, depending on the vicinity and the client. In both instances, the building procedure is the same, although some differences in graduated table of operations may happen.
After the planning and study phases, the first measure in the building procedure is the infrastructure. The infrastructure is that portion of the edifice that is below the land degree. Its intent is to safely convey all forces to the land. Traditionally, the infrastructure will dwell of a series of pad foundations, strip termss, cellars or even hemorrhoids. Most of the old houses have cellars whereas newer houses tend to hold strip termss. Taller edifices such as flats or where the edifice is on weaker evidences, hemorrhoids may be required. All those foundations are by and large formed by delving a hole in the land and make fulling it with concrete. The form, size and deepness of the hole depend on the type of foundation being built. Foundations are labor-intensive and time-consuming work. All of the work has to be done on site, exposed to endure conditions. It besides produces important sum of noise and dust during the excavation of the land. Once the trenches or holes are filled with concrete, the site ends up with an surplus of dirt from the hole.
The superstructure is the seeable portion of the edifice, built on the foundation. The construction for houses will dwell of constructing up brick walls from the land, brick by brick. Each wall will dwell of two foliages of brick with a spread in-between for insularity. The internal floors are by and large made of heavy lumber joists back uping secondary lumber members and eventually a board topping, all nailed together and supported off the brick walls. The brick wall building will go on until the roof degree is reached. At the roof degree, a lumber roof is built in a manner similar to the floor.
Recently, concrete columns and beams have been used along with the brick walls. Floors and roofs in newer building tend to be on concrete, cast in-situ on formwork, supported off the concrete frame members. These methods are really time-consuming and labour intensifier and about all the work has to be done on site.
Partitions and Coatings
The internal dividers are either timber frames with ply-wood on each side, or single-leaf brick walls built in the same manner as the external walls. Stairss are by and large of wood.
The infinite warming, electricity, air-conditioning and airing are all built to accommodate the edifice in topographic point.
Modern Approach to Construction
As opposed to the traditional method where each measure of the building is done independent of each other, the modern methods of building differ right from the attack to the building procedure. The thought procedure behind the site works is done good in progress, to let much better coordination between the assorted trades involved. The planning phase will believe of the proposed and future utilizations of the edifice. The design phase is the most of import phase of building as determinations taken at the design phase have the highest impact of public presentation, economic system and many other factors.
The attack to modern building is one that takes sustainability and life-cycle cost of a edifice right from the oncoming of the design phase. Many factors can be influenced if thought is given at design phase. The undermentioned chapters will now present modern techniques used in building that will ensue in more economic and sustainable building in the lodging sector.
Steel Framed Buildings
The usage of steel is non new in building. It has been used for over a century now. However, its full potency has merely late been understood. Steel has the possible to radically alter the edifice and running cost of a edifice every bit good as holding a major impact on issues such as sustainability, material demand, wellness and safety and so much more. Developments made over the past decennary in steel building have made it the most exciting stuff for building.
Steel ‘s Role in Sustainable Development
Steel is a wholly different stuff from concrete and masonry. It is first of all homogenous as opposed to a mix and is much stronger. The UK steel building industry in a really efficient industry and steel can be used to our advantage as a modern building stuff for several grounds that will be unveiled below ( SCI, 2004 ) .
More sustainable Design
Good design is cardinal to sustainable building ( SCI, 2004 ) . Decisions made at the initial design phase have the greatest consequence on the overall sustainability impact of undertakings. Steel ‘s high strength-to-weight ratio is exploited in light constructions which have low overall environmental impact and frequently necessitate fewer and lighter foundations than alternate methods of building. Its long-span capablenesss create flexible infinites that facilitate alterations in usage during the life of the edifice, maximizing allowing possible and reducing refit costs.
The energy associated with the business of edifices ( operations energy ) dominates that used in their industry and building ( corporal energy ) typically by a factor of between 4 and 10 over a 60 twelvemonth design life. Reducing operational energy ingestion reduces environment impact every bit good as salvaging money. Steel frames and associated composite or other type of floor slab achieve high degrees of fabric energy storage, which can significantly cut down the energy measure for chilling. Steel-based cladding systems for industrial edifices and light steel-framed residential building provide well-insulated and air-tight solutions.
More sustainable industry and hard-on
Construction can hold important societal and environmental impacts such as noise, dust, land and surface H2O pollution and traffic congestions ( SCI, 2004 ) .
Steel provides the chance to maximize off-site building techniques. Working in a mill under controlled conditions will decidedly ensue in more accurate merchandises and less waste. It besides provides a safer and better working environment for the workers.
Computer-sided design and industry can be put to best usage in steel building to extinguish defects and reworks and to understate waste. Any steel waste is by and large recovered and recycled. Cost, and hence clip, remain cardinal drivers in building. Steel building allows us to construct fast and faithfully, with minimum clip spent on site. The little sum of clip spent on site has many impacts such as lower noise, less clip for the workers to work every bit height, less noise and dust, less traffic and the whole community benefits. Less clip spent on site besides has the advantage of fewer breaks due to endure, which is a really of import factor in the UK, because our conditions is universe celebrated!
As an illustration of what can be done ( SCI, 2004 ) , the 1600 metric tons of steelwork in the TNT Fastract distribution Centre was erected in merely 21 yearss!
Sustainability in Use
Planing a edifice for long life maximises the payback over the initial investing and is besides a cardinal facet of sustainable building. In that regard, renovation of a edifice to widen its life is really of import. The versatility and flexibleness of steel licenses the proprietor of the edifice to easy modify and accommodate to altering clip without holding to pulverize and reconstruct, therefore widening the life of the edifice and acquiring the most value out of it.
Steel is a stable merchandise and if protected from the environment with pigment, will necessitate small care and will non deteriorate at all with clip. Cladding systems associated with steel building are besides easy modified and allow easy entree for care.
With altering times, the demands of a edifice alteration and therefore alterations may be necessary. Steel is easy to modify and to widen to suite new demands.
Sustainability at end-of-life
A concrete constructing merely has a market value as a built-entity. The stuff itself can barely be reused because it is cast-in. and can non be dismantled. The best usage of dismantled concrete is land-fill. However, steel edifices have a stuff value even after building. Because steel edifices consist of independently prepared members joined together by bolts, these members can be dismantled and re-used if the edifice is no longer required. For illustration, when the assorted Paris market halls built by Baltard in 1854 could no longer fulfill the demands of the metropolis ( ECCS, 2002 ) , their map was transferred to Rungis, and the edifices replaced by the Centre Pompidou and the Forum. Recognizing the demand to continue of import architectural illustrations from the past one of the market halls was demounted and transferred to Nogent-sur-Marne, where it was merely reconstructed. It now accommodates cultural activities.
The fact that a steel edifice can be demolished and rebuilt utilizing the same structural members has far-reaching advantages. The immediate advantage that comes to mind is the market value of the edifice. Of class, a edifice has a value when it is in usage. But with the usage of steel, the edifice will hold a value even after its life-span. The steel members can be sold as separate entities or the whole edifice can be sold to be built on a different site. This contributes tremendously to the cost of renovation and therefore can be used to cut down the cost of lodging.
Looking at the bigger image, re-using the same stuff for a new edifice implies that the natural resources that would hold been required for the new edifice have been spared. Finally, even if the steel is non re-used straight as a building stuff, it can ever be recycled for new steel members. Steel is 100 % reclaimable stuff.
Energy in Buildings
In edifices, energy is required for:
- Space warming
- Domestic hot H2O warming
- Mechanical airing
- Air conditioning
- General electrical services such as lifts and escalators
The measures of each of the above required vary from topographic point to topographic point and from constructing to edifice.
In UK as in the remainder of Europe, infinite warming is traditionally achieved by gas-powered or electric powered hot H2O boilers that distribute the hot H2O to radiators. The envelope of the edifice is designed to retain as much of that heat as possible to salvage on energy. However, there are several advanced techniques now available that are really efficient.
New Glazing Technology
There are new types of glazing that allow the solar heat to travel into the edifice, but non out. Double glazing systems have been used for many old ages, but now the double-glazing makes usage of particular spectacless. The spread mediate the spectacless can be filled with particular gases that promote the nursery consequence. In some instances, merely evacuating the air from the spread works wonderfully in moving as a smart glazing system. There are spectacless that can be switched from clear to opaque by the action of current, heat, or of course similar dark glassess. New cladding stuffs used on the walls are semitransparent. They transmit light and solar energy but act as insulating materials.
Synergistic Windowss and shadowing system are computer-controlled to alter the degree of shadowing and airing at different times of the twenty-four hours to optimize energy usage.
Direct sunshine is used to warm edifices. But solar energy can be used indirectly every bit good. Solar H2O warmers are really popular in the Southern Hemisphere. In Europe and particularly in Western Europe, people have the misconception that because of the cold clime, solar H2O warmers will non be effectual. In fact, solar H2O warmers are really efficient even in cold parts. It is besides really inexpensive to construct or purchase one. It can be used on big graduated table for schools and infirmaries with big roof programs. So alternatively of boiling H2O in a gas or electric boiler, solar H2O warmers can be used. Even if in winter the solar H2O warmer can non bring forth sufficiently hot H2O, it can still be used to preheat the H2O supplied to the boilers.
In many states, infinite warming is required at dark more than during the twenty-four hours. In such instances, the mass of the edifice can be made to heat up during the twenty-four hours by the solar energy methods described supra. This mass will absorb this energy during the twenty-four hours but will merely get down dispersing it after several hours. Concrete floors for illustration will hold a typical clip slowdown of nine hours. Proper usage of this thermic mass can take to really important economy in energy. The orientation of the edifice can play a important portion as good. For illustration, if the south face is the 1 that is most open to direct sunshine, holding more monolithic walls on the South will better on the usage of thermic mass.
Domestic Water Heating
Domestic hot H2O is used in about all edifices. Solar H2O warmers as described antecedently are by and large really effectual for domestic hot H2O. Other methods can besides been used, depending on the location. If a small town is situated non really far from a vent, they can normally delve deep boreholes and pump the H2O to the underside of the hole where the Earth temperature is rather high. They can pump back the H2O and utilize it as domestic hot H2O. The construct is non a new one. Thermal watering place and natural hot H2O baths have been used for centuries.
The orientation of a edifice can be really of import to do usage of every bit much natural visible radiation as possible. Smart glazing systems discussed earlier are besides really utile and are used more and more now. Lightwells and atria are besides more and more used both for its aid in natural lighting and airing, but besides for its aesthetic parts. When unreal lighting is required, particular low-energy bulbs can be used that give the same sum of visible radiation but consume smaller sum of energy.
Natural airing has ever been used in houses by merely opening and shutting Windowss as required. Commercial edifices have nevertheless opted for more hi-tech methods such as fans. These can be replaced by careful planning of the gaps, of the manner the floors are compartmented, and by the usage of characteristics such as atria. Besides, computer-controlled gaps are the hi-tech version of manually opening and shutting Windowss as required.
Cooling is ever more expensive than heating. Not merely does air conditioning devour a batch of energy ; it besides releases CFC ‘s, which are harmful to the ozone bed. The usage of these can be minimised every bit good. The usage of airing can be used to better the comfort degree of residents. The usage of the thermic mass construct can besides be used in the same manner. The floors are cooled at dark utilizing natural airing, and during the twenty-four hours, they are used to chill the air inside the edifice.
The purpose of the study was to suggest and warrant modern methods of building. The study has exposed the necessity to switch to modern methods of building. It is non merely an option worth sing. It will shortly be the lone option and unless we as a company get down the displacement now, we will free a competitory advantage.
Among the modern methods mentioned, steel building comes out to be the flagship of modern, economic and sustainable building methods. Added to that, other agencies such as utilizing thermic mass, natural airing and natural warming and chilling can be used in combination to fantastic consequence.
However, the most of import point to retrieve is non the stuff or any peculiar technique. It is the attack and the thought procedure required to run into the economic demands of the company, satisfy demands from the authorities and other governments and yet be able to bring forth low-cost and high quality and high public presentation lodging for the hereafter.
Egan, Sir John,Rethinking Construction, Department of Trade and Industry, 1998
David Stern and Daniel Knapp, Reuse,Recycling, Refuse and the Local Economy: A Case Study of the Berkeley Serial MRF( documented by Urban Ore, Inc. , and The Centre for Neighbourhood Technology: October, 1993 ) .
Boontra Chiel,Sun at Work in Europe, Vol. 12, No.1, March 1997, p3.
Nicholls, Richard,Low Energy Design,Interface Publishing, 2002
European Commission for Constructional Steelwork,Merits of Steel, 2002 hypertext transfer protocol: //www.szs.ch/merits/vorwort_e.html
Achieving Sustainable Construction: Guidance for clients and their professional Advisers, Steel Construction Institute, 2004