Timber Frame Housing Construction

spirit pattern Housing Construction baseb any bat reference clay accommodate a viable alternative to masonry Construction1.1 IntroductionChapter integrity of this dissertation leave behind review relevant articles of primary and secondary data to value the hypothesis Timber Frame tress a viable alternative to masonry edifice.The main objective of this literature review is to increase the k without delayledge and understanding of the research and to critically s break word all that has been researched on tint mould construction in comparison to masonry construction.The literature review leave be categorised into the fol emiting argonasEnvironmental matchFactors effecting Construction Costs. ( time savings, prelim costsBarriers effecting lumber encloseFire resistance, acoustic, Thermal etcThe literature review comp ares the opinion of other researchers and what they have disc overed and through in relation to such aspects in tinctureland butt against construction1.2 Environmental impact of lumber frame construction in comparison to masonry construction.1.2.1 MaterialsRoaf (2004 p.13) quotes buildings are our 3rd skin. To survive we need shelter from the elements using three skins the first is provided by our own skin, the second by a layer of clothes and the third is the building. In some climates it is only with all three we arouse provide sufficient shelter to survive, in others the first skin is enough. The much than extreme the climate, the more we have to rely on the building to protect us from the elements. Just as we take off and put on clothes as the hold and the climate changes so we notify alter our buildings to adopt climate changeTherefore one must investigate which rule of construction is best desirable to ones needs taking into account costs, environmental consequences and aspects such as caloric, acoustical and wake resistance so accordingly they evoke animateness in a comfortable dwellingThere appears to a be a hu ge demand in the construction industry to improve the energy in buildings, in that locationfore to control climate change and to make this happen one must look firstly on the construction of our buildings and what manner has the best impact on the environment.The author feels there is a strong case for investigating the woodsland frame approach as it has a potential for creating sustainable al-Qaedas.Practices such as energy efficiency, recycling and the implement of sustainable materials and products need to become inherent parts of the design and construction process and in some cases, displace handed-down construction process and practices sustainable homes (2000), As Some materials purposed in construction can damage the environment they can create pollution, while others are produced in an energy intensive process. Reclaimed material and products do from recycled material are less likely to cause environmental damage. It is classical that materials should be judged o n their lifecycle and their performance once they are installed.Buchann and honey, (1994) as well suggest that there is a growing awareness that in the choice of building materials, the designer must non only consider the traditional requirements, but overly the re pedigree base and the effects on the environment of extraction, get and processing of the building material, as the list of primary energy used can have huge effects on greenhouse gas emissions.Borjesson and Gustavasson (2000) agrees with this rehearsal as he suggests that,The substitution of sustainability produced woods material for other construction materials can reduce net Co2 emissions, Quack (2001) is in support of this statement with after(prenominal) the results of his study show that the life cycle of each house is independent of the construction materials.Sustainable homes (2000) discuses that timber is possibly the only renewable resource in the construction sector.According to Timber construction (200 7) timber frame construction is the only environmentally friendly material available, as it claimed to be a degree centigrade neutral. Claiming 800 kg of carbon dioxide is deliver for every cubic meter of wood used. Stating that when comparing a 100m2 timber frame and masonry house, a total of 4 tonnes of carbon dioxide could be saved as a timber frame dwelling contains 5-6 cubic meters mores timberIPCC (1996) agrees that the manufacture of wood products normally requires less energy than that of alternative product which in results compares to the statements made above.Noren (2001) studied timber frame and traditional masonry houses over their lifecycle and claims that timber frame houses are a crack environmental change to implement as carbon dioxide is reduced on every stage of the buildings life. Sutton (2007) is in agreement with this statement, claiming timber frame emit 16.5 % less carbon dioxide over the life of the building in comparison to its counterpart masonry constr uction.But still Brunklaud and baumann (2002) suggest after having examined reports on the environmental impacts of different materials on timber frame and masonry construction that wood has the worst environmental impact in terms of embodied carbon dioxide emissions, but however over a complete lifecycle, building operational emissions is the most important factor regardless of the materials chosen, and that it is improvements to reduce operational emissions that will benefit the overall environmental impact of a building.Bjorklund and Tillman (1997) also agree as results show that timber frame has a better environmental impact at manufacture stage but however masonry can match timber frame over the life of the buildingSustainable homes (2000) indicates that buildings accounts for 50% of all co2 emission and on average a house produces 7.5 tonnes of co2 every year, four tonnes if create to current regulations.It is not therefore, rugged to see the benefits of increasing the in sulation capacity of the building envelope as one mechanism for cut down the quantity of fossil fuels required in running our homesThis statement above agrees to such statements from the majority of authors such as Buchann and honey, Borjesson and Gustavasson, Brunklaud and baumann, that a great deal thought should be put into materials such as the fabric, structure of your house and your insulating materials therefore reducing the need of burning fossil fuelsAlthough timber frame has a better environmental impact at manufacture stage from reports above it can be argued that masonry can achieve as a unspoiled an impact on the environment as timber frame over the life of the building.1.2.2 Waste ImpactA dictionary definition of environment fumble is that of any substance, full-blooded, liquid or gaseous for which no use can be make by the organisation or system that produces it for which a method of disposal must be devised. (RICS, 2009)However (Mnyani 2003, pg4-5) describes it as any waste that is generated during the process of construction, leftovers that are to be disposed post construction and this includes end debris.The construction industry is one of the largest industrial sectors in the UK,Construction and demolition waste represents roughly 17 per cent of total waste production in the UK, making the construction industry the largest generator of controlled waste in the farming (DETR, 1999). It is estimated that some 70 million tonnes of construction and demolition waste arise annually (Environment Agency Website, 2000).Ekanaye Ofori 2000 indicate from their study on 230 different building sites, they found that waste levels for specific materials is consistently gameer than the estimated level for all materials studied. New purchases to replace wasted materials rework to correct mistakes, delays and dealing with generated waste cause arduous financial losses to the contractor.Therefore the author feels the use of timber frame constructio n will play a good habit in reducing waste as the timber frame panels arrive on site and are erected in a matter of hours in support of this (Glynn, 2000) points out that arriver on site timber frame kit and erected in less than a week, approx 1 4 daysThis therefore cuts out on materials been shamed as a result of lying around the site, but however (Johnson, 1981p6) states that Waste occurs on site for a number of reasons, most of which can be prevented, this waste can occur form the Misinterpretation of drawing, Overestimating of quantity required, Faulty workmanship and Careless handing of materials.From this statement timber frame construction exceeds masonry as wastage on site can be reduced significantly by the maximum use of prefabricated units. As well as reducing wastage, quality control and efficiency during manufacture of standard materials in the factory means that the net amount of material required for production of the final component is minimised. Factory conditio ns make the use of off cuts more likely.Recycling and reuse of materials have long been associated with wise construction practises. Experienced contractors are now reaping the economic advantage of construction waste management. Many of the contractors that have embraced waste management have made changes to their operation and practices to take advantage of reduced waste disposal costs and revenues derived from recycle, reuse and deliver materials. Utilizing, reuse and salvage methods on site reduces materials that end up in the landfill, creates a cleaner and safer project site and improves community relations.1.3 Factors effecting costs.Mark Windsor spokesperson for picture and Materials Company suggests that costs for masonry are the same for timber frame houses http//www.designandmaterials.uk.com/materials/brick-and-block.htmlTo evaluate this statement Glynn (2000) demonstrates a construction course in the following charts.Timber Frame ProgrammeFoundations for kit are prepa red, approx 1.5 weeks.Arrival on site timber frame kit and erected in less than a week, approx 1 4 days. foreign doors and windows fitted to seal house from foreign elements, approx 1 week.During phase three the roof is erected, felted and battened and tiled, approx 1.5 weeks.External cladding ideal approx 1.5 weeks.During phase five, first concern electricity, measure and carpentry can begin, approx 2.5 weeks.Internal wiring and pipe work to be complete, approx 2 3 days.Drying out design, approx 2 4 days.Start second fix services, approx 2 3 weeks.Decoration can now begin and client takes over.This concludes timber frame programme at twelve weeks.Source (Kenneth Glynn, Prefabricated timber frame construction, 2000)Traditional masonry programmeFoundations for kit are prepared, approx 1.5 weeks.Masonry envelope can commence approx 4 5 weeks.About one week after envelope commenced, fix and glazing the doors, approx 3 weeks.During phase three, the roof is erected, felted and battened and tiled, approx 1.5 weeks. Note scaffolding will be on site for the majority of the above.During phase five, first fix electricity, bathymetry and carpentry can begin, approx 2.5 weeks.Internal wiring and pipe-work to be complete, approx 2 3 days.Start second fix services, approx 2 3 weeks.Decoration can now begin and client takes over.This concludes traditional masonry programme at near twenty weeks.Source (Kenneth Glynn, Prefabricated timber frame construction, 2000)In examination of the construction programmes, there is a large differential coefficient in time scale between inception and move in dates. It is possible to come to the conclusion based on the solid facts that the programmes portray to us that the development of the timber frame house is by far the most efficient in terms of speed in completion. The residue in weeks is quite substantial with the programme of development comprising of the timber frame method of construction far more efficient with an overall saving of about eight to nine weeks. A timber house is usually watertight by week five of the build by contrast a traditional masonry house is not watertight for nine or ten weeks. Traditional construction methods are extremely vulnerable to inclement weather conditions. Such inclement weather conditions will cause delay to the overall completion of the project, this is not a factor for timber frame construction as all privileged works can began at week five, despite any external weather conditions.By Glynn 2000 contrasting these two construction programmes it shows that the timber frame programme would offer a rapid development construction to meet market demand thus providing a return on your development nigh of warm effect.In support of Glynn an article in built it magazine states When comparing timber frame to masonry, masonry is generally the slower of the two.However this article indicates one must factor in time it takes to get a timber frame onto site from the dat e it is ordered, which can take up to 16 weeks ( Build It magazine, make May 2008.)However from examining Glynn 2000 construction programme there are direct costs saving advantages such as reduced construction time, overheads and less waste. former(a) factors that should be considered when carrying out a cost benefit analysis are the preliminaries costs as early off-hire of cranes and scaffolding due to reduced construction clock and also reduced on site labour which saves money. With brick and block, build costs are spread over a longer period of time. However one must consider the overall programme cost reductions by timber frame construction.Timber Frame is touted to have the following advantagesThat it is a faster method of construction with the ability to halve the total on-site construction durationThat it requires less on-site labourThat large number of units can be constructed indoors a short timeThat the faster construction and reduced on-site work brings financial benef its to the developer in terms of shorter period of financing the project and completed buildings being put up for sale much faster.Factory-produced homes are usually erected on site in a matter of days. Once up, the internal finishes can be started right away, which can produce further time savings. However, there may be lengthy delays involved in getting the frame built. to a fault bear in headway that thin-joint masonry promises many of the speed advantages of timber frame. The NHBC estimates up to a three-month time saving by choosing timber.On PriceFor many age, timber frame used to be thought of as a little more expensive, but advocates claimed that you could claw back any extra expense by shortening the length of the job overall, thus reducing overhead and finance costs. However, more recently the picture has become confused. Blocklayers became very expensive, eroding the cost differential while timber frame factories became very busy, lengthening the time taken to process t he orders, and thus losing much of the speed advantage. The fact is that there really isnt that much cost difference. As a rule, masonry sits better (and cheaper) behind a brick or stone skin, whilst timber frame comes into its own behind a lightweight external skin such as timber.Representatives of both timber frame and brick and block would agree that there is relatively not much of a difference in the cost between the two constructions techniques. If timber frame is chosen for its quick build time,One believes that overall the cost benefits of timber frame houses offer better value as the proposed development would include rapid construction to meet market demand thus providing a return on your development almost of immediate effect. . The speedy construction of timber framed houses enables the contractor to construct a large number of houses in a relatively short period of time. A timber frame house owner would also have the added benefit of a more energy efficient home1.4 Perce ption of timber frame and its barriersThe use of timber frame construction of houses has faced many challenges in recent years as other materials such as sandcrete blocks, cover blocks and brick replaced timber as main building construction materials due to many barriers such as psychological barriers mainly form general public.The public experience of timber frame construction in comparison to the traditional masonry construction. B.k. Baiden, E. Badu, F.S Menz (2004) is as followsTimber can consumed by set down if used in building construction, force is relatively poorstructural abilityThe lack of understanding and cynical views expressed by the public on the fire resistance, durability and structural properties of timber frame structures initially made Timber frame construction to received negative comments throughout the last hardly a(prenominal) decades and has came under scrutiny which has influenced the negative erudition the general public have adoptedThe timber frame i ndustry was effectively killed off overnight in the early 1980s, after the world in action programme raised a number of doubts about the standards of construction Barrys (2002)Timber frame construction has received negative comments throughout the last few decades and has come under scrutiny which has influenced the negative perception the general public have adopted. Some members of the public associate timber with been a fuel for fire and therefore timber frame structures are more liable to ignite. The author feels this is a harsh and unjust assessment, which has restricted the growth of timber frame housing during the 1980s and the early 1990s when it could have gained a valuable foot hold in the housing market during this period. However in recent years the only slight concerns remain in the public domain and this has helped timber frame housing to gain a 30% share in the house servant housing market. Many professionals in the timber frame industry believed that consumers no lon ger had doubts regarding fire, which will be illustrated later in the questionnaire conducted by the author.Government reports indicate that There are some residual reservations about timber frame among architects, engineers, builders, administrative bodies, financial institutions and insurance companies as well as with end users. perceive problems with timber frame construction in the housing market from both the end users and local authorities would include a perceived greater stake of fire, issues of croak attenuation in a timber structure and the impact such a structure might have on the security of the end user.however Narty 1971 states that Timber constructed houses can be built to last for a period of 40-100 years, this suggests that timber frame construction is every bit as good as the traditional masonry method.Most people perceive a brick block house to be more solid than timber framehttp//www.buildstore.co.uk/mykindofhome/events/different-building-systems-weekend-in-d etail.htmlTraditional masonry colliery walls, most commonly brick with an inner structural leaf of concrete block, have dominated house building in the UK for the past eighty years, but there are a number of other systems that are gradually making inroads, including timber frame,http//www.cyprus-property-buyers.com/files/constructionmethods.pdfOne question that perpetually raises its head is which is cheapest of the two most commonplace systems timber frame or brick and block?The author will look in great detail at the properties in timber frame buildings to evaluate the perception in the industry towards timber frame and why they think masonry is the better construction overall.1.4.1 Fire resistanceBarry (1998) states that although timber is a combustible material, it can function as a structural member for a longer period than an unprotected metal member provided it is of adequate sectionWhite (1999) agrees with this statement sayingThe relatively good structural behaviour of t imber in fire is due to the fact that it has uniform strength through the mass. The load posture capacity is therefore reduced in proportion to the loss of the cross section, the unburned section, however, retains a full high strengthForest products research institute (1988) also agrees with this as the results from a study showed that timber of sufficient size is difficult to burn because of cross sections decompose relatively slowly due to its low thermal conductivity and the formation of charcoal on the outer sectionsSustainable houses (2000) agrees with the above as it states that timber frame homes tested to BS476 demonstrate that they exceed these requirementsBRE structural appraise (2002) indicates that in the TF 2000 BRE project no evidence to suggest that timber frame construction suffers disproportionally form problems of poor workmanship or that it is exposed to higher risks of fire spread than traditional masonry counterpart.In support of this TRADA and BRE fire safety research concluded that Timber frame performs as well as other construction in fire and life safety is at no greater risk.1.4.2 ThermalSustainable (2000) suggests that one of the most commonly identified advantages of timber frame systems in relation to thermal performance, The most important factor by far being the structural envelope.The most basic timber frame home will exceed current building regulations requirementsIn support of this statement Doran (2008) BRE states timber frame insulation solutions lend themselves to going significantly beyond the stripped-down thermal performance requirementsTimber frame can easily meet current regulations by increasing stud size therefore increasing the amount of insulation, giving a better U-value.With the governments publication of new regulations in 2006 part L relating to energy conservation and ventilation in new homesTimber frame uk suggests that with the introduction of these new part L regulations for new built homes timber frame housing has increased because of its suitability for modern building and it can fall out with the new regulations so easily and cost effectivelyWith timber being a poor conductor of heat Barry (1993), the thermal conductivity is very low making it a natural insulator which is two to four times of common insulating materials Simpson (1999)However Doran 2008 indicates that to achieve the expected thermal performance in timber frame dwellings requires good workmanship1.4.3 AcousticSound is a form of energy which can be transmitted over a distance from its source through a medium, such as air or a solid element of construction e.g. a wall or a floor.A construction based website Homebuilding.Co.uk indicates that heavyweight building techniques have a clear advantage here. But in detached housing, the chief area of concern is stochasticity between floors and most masonry homes actually have timber intermediate floors, so in this respect there is little differencehttp//www.homebuilding.co .uk/feature/construction-systems-masonry-vs-timberSustainable (2000) indicates that timber frame masonry outperforms masonry society walls by some marginIn support of this Trada (2000) agrees with this statement indicating lightweight timber frame companionship walls between semi-detached or terraced houses and flats and company floors between flats meet the current requirements of the building regulations for reasoned insulation. However many authors argue this (.) stating that building mass is the only way to provide high sound insulation.An article by Clive Fewins, published in home building and Renovating magazine agrees with the above statement with regards to the public perception, where the public perception of masonry built is strong and invariableA masonry structure gives a house a feeling of solidity, as the density of the blocks provides a high level of acoustic massTrada state Its raise that even our standard 140mm timber frame walls are 20 per cent more thermally e fficient than current building regulations demand. Sound insulation is more efficient too with a timber frame, compared with other methods of construction.This public perception of the acoustic performance of timber frame has also played a role in hindering the growth of timber frame housing but these unsubstantiated views have been contradicted by a number of independent assessments within the industry.However BRE are in favour of timber frame building stating, If all dwellings had sound insulation as good as that measured in party walls of timber frame homes, the problems of noise from neighbours would be greatly reduced.Just like any other new homes, when built with good standards of workmanship, timber frame homes will meet all current Building Regulations and Standards on sound insulation and acoustic performance. It is commonly assumed that only solid walls that are found in traditional masonry houses can guarantee you peace and quiet. In 2003 tests were carried out by (BRE) t he Building Research establishment on Robust Details that can be used by any designer and house builder, this research proved that timber frame houses performed best out of any construction method. This research was also reviewed on the UKs largest database of test cases on sound performance going back over 17 years, by Dr Sean Smith of Napier University who also stated the superior sound performance of timber frame houses.A statement from Dr Sean smith in a recent website article on timber frame construction shows after researching on acoustical performance how he personally feels timber frame can easily outperform current regulations Our research shows that timber frame party walls are the best performing in the industry for current and future regulations.The (Irish timber frame association) suggest the importance of mass has always been perceived as been vital to achieve good sound insulation, however reliance on mass alone would be impractical and a largely unpopular method of improving sound performance. In recent years other characteristics have became more important such as isolation, stiffness, absorbency and air tightness. Isolation makes it more difficult for sound to propagate through the building by introducing physical breaks, this is an important for good sound insulation, and the cavity walls in both house types perform this function. ineptitude of structural members, gives greater resistance to structure borne vibration caused by sound. Absorbency in voids helps dampen sound and finally by ensuring the separating structures are totally sealed, sound leakage through gaps is avoided. It is widely accepted that timber frame construction is exploiting these characteristics and is well ahead of other methods when the regulations change in the future.Noise nuisance within homes is beseeming a more widespread concern in modern times as ownership televisions, stereos and game consoles are at an all time high and this is causing conflict among neighb ours. The findings of BRE have contradicted the public perception that mass is essential to gain high-quality acoustic performance.Durability Narty (1971) argues that The Durability of timber is often discussed with reference to fungi, or insect attack. In absence of these, timber is remarkably resistant and will survive for long periods of time the author has found such evidence as the Egyptian tombs which are over 200 years old.BRE (1996) conducted two large scale independent surveys and found no instances of rot caused by water ingress. And all timber exposed areas (Cavity) that are preservative treated shall cause little troubleIn support of this Simpson (1999) agrees with this statement suggesting that timber kept constantly change does not decay and a large proportion timber used is kept dry and can last for very long periods1.5 Advantages of timber frame over masonryTimber frame offers a number of advantages compared to most other forms of constructionThe previously stated t he u turn for the rise in popularity for timber frame methods of construction has not been unfounded, with large benefits to the client and contractor been identified as the basis for this success. Many of the countrys contractors in the housing are now sternly considering this technique because it,provides high quality houses, quickly and cost effectivelySource (Prefabrication-solution to an overstretched industry, Nov 2001, The Irish construction Industry Magazine) The greater use of well-designed timber frame houses will help ease the pressures on traditional construction trades, it also has the benefit of helping to speed up projects and help ensure cleaner and safer sitesSource (Webb, M., The construction magazine, Prefabrication Report)On SpeedFactory-produced homes are usually erected on site in a matter of days. Once up, the internal finishes can be started right away, which can produce further time savings. However, there may be lengthy delays involved in getting the fram e built. Also bear in mind that thin-joint masonry promises many of the speed advantages of timber frame. The NHBC estimates up to a three-month time saving by choosing timber.