Presentation on theme: "Let’s talk about Conventional / Traditional Construction…"— Presentation transcript:
1Let’s talk about Conventional / Traditional Construction… Knowledge Hub…We at OxyGreen believe in sharing knowledge as well learning anything and everything that is innovative & helpful to the field of Construction as well a hand to save our Mother Earth.
2Conventional / Traditional Construction Bricks and mortar is a phrase that readily springs to mind when it comes to house building - and with it connotations of a solid, secure structure. From the wooden building blocks and Lego of childhood to talk of 'investing in bricks and mortar', or 'the building blocks of life', there's something very safe and familiar about bricks.A masonry build is something that lasts, too - you only have to walk down a street in any city to see that. In fact, brick-and-block construction is the cornerstone of the self-build market, with around 70 per cent of self-builders opting for this method.You only have to look at the Egyptian pyramids or Greek temples still standing to realize the permanence and enduring beauty of masonry construction. Building with concrete is not new—this construction method has been used for residential construction throughout the world, for centuries because of its strength and durability.
3The Conventional Construction Process Traditional masonry construction refers to houses built in block and brick. Although brick is used countrywide as an outer skin or 'facing material', it is often substituted with local quarried stone or a reconstituted replica.Despite the use of the term 'traditional', masonry construction has incorporated many modern developments and has come a long way since the days of solid stone walls. Improvements in technical design, materials and accessory products have enhanced the performance of these structures significantly in terms of structural integrity, thermal efficiency and moisture protection. Progress has led to developments such as thin joint systems with Aircrete blocks."Concrete masonry construction offers many advantages in terms of termite resistance, thermal mass, sound attenuation, and fire resistance."The Conventional Construction ProcessFollowing excavation and installation of foundations, bricklayers erect cavity walls that consist of an inner and outer skin.The inner skin is the main structural element, which supports internal floors and the roof structure. It is constructed using concrete blocks laid on beds of sand and cement mortar.The outer skin is the first line of protection against the elements and provides the aesthetic element to the structure. It is constructed using brick, stone or block work, which can take a number of finishes. The two skins are connected by steel wall ties and separated by a cavity that is partially or fully filled with insulation.
4The Conventional Construction Process Contd… Internal floors can be constructed using timber joists, composite timber I beams, or one of the precast concrete systems available. The roof is usually traditional cut timber or prefabricated truss construction.Once the roof is completed and the windows and doors are fitted, the building is watertight the internal trades can get underway. The internal face of the block work can take a range of finishes including 'dot and dab' plasterboard and wet plaster.Various details are required around openings and other parts of the structure in order to maintain structural integrity and to prevent water penetration and heat loss.We'll have a look at masonry construction and the advantages and disadvantages of choosing it as the method of construction for your dwelling.
5What is brick-and-block in Conventional Construction Brick-and-block involves working entirely on site - unlike build techniques such as timber-frame. The build starts with concrete foundations and finishes with the roof. Walls consist of a block-built inner skin, a cavity, and a brick-built outer skin. The two skins are held together with wall ties to add strength, while the cavity is filled with insulation. Internal load-bearing walls are built in block. All walls are built to first-floor level at which point timber floor joists or pre-cast concrete floors are added before the build is completed to roof height. Once, watertight, internal block walls are finished using board or wet plaster.
6Conventional Construction – Advantages It is a flexible system in both design and construction.Depending on your house design and the materials specified, masonry construction can be one of the most cost effective of all the build methods.As the most common form of house construction, there are plenty of tradesmen and specialist knowledge available to complete your project.A proven track record means it is accepted and understood from designers and builders to lenders, insurers & warranty providers.Materials are readily available from local builders merchants.Materials are often manufactured and sourced locally (Traditional Housing Bureau).Easy to modify or extend.Good levels of sound insulation are achieved, which can be improved by using precast concrete floors.Masonry provides good fire protection.Masonry materials are strong, durable and long lasting, spreading their impact (Traditional Housing Bureau).
7Conventional Construction – Advantages Contd… Good thermal performance. Masonry materials have a high thermal mass, which is their ability to absorb and store heat. In the summer this keeps the building cool and in the winter the heat stored during the day is slowly released back into the house at night leading to a more constant, comfortable environment. This effect is improved if plaster is applied directly to blockwork in lieu of dot and dab plasterboard.When the building has reached the end of its useful lifespan, bricks and blocks are 100% recyclable (Traditional Housing Bureau).Resistance to hurricanes, tornadoes and other weather-related phenomena since the entire structure is tied together from the footings to the roof assembly with steel reinforcement, achieving a a natural strength of 400 pounds per running foot compared to just 80 pounds for wood framing
8Conventional Construction Disadvantages On-site construction means that progress and your program of work can be affected by adverse weather conditions.Materials need to be stored on site and protected from the weather before they are incorporated into the building structure.New work needs to be protected from the elements.On site construction is labour intensive.
9Quality Issues in Conventional Methods & Materials Conventional designs that compromise beams, columns, brick/block infills & plastering have inherent inefficiencies during construction. Brick/block wall infills are labour- intensive & cement-sand plastering, a wet process, is often messy & requires more preparatory work. There are also constraints in concealing & routing M&E services. Apart from using more intensive manpower & longer construction duration, there are some inherent difficulties in achieving high quality. Please find given below, information on the challenges posed by such conventional design & materials.Consequences in choice if internal finishes - Choice of methods & material affect workmanship quality
10Traditional formwork system: More joints & poor surface finish Traditional formwork system has more connections & joints & it requires more manpower to erect, maintain & dismantle. During erection, close monitoring & supervision is needed to achieve the desired workmanship quality of the finished concrete. If the formwork is not erected properly, the end product would not be satisfactory. Often this means another layer of thick plaster is required to cover the uneven concrete surface.Traditional formwork system: More housekeeping.Poor concrete surfaces: Thicker plaster is required
11Restricted M & E services run Many services in a building e.g. electrical, ACMV & sanitary plumbing, etc are concealed under slabs or covered by false ceiling. If there are too many beams, especially non-shallow beams, it may be difficult to locate such services under floor slabs. This may restrict the height of false ceilings or the floor storey height may need to be increased to accommodate such services.More columns & beams: Limit M&E services run Internal beams restrict height of false ceiling
12More turns & cornersThe width of RC column may be different from the width of the brick wall laid against it, especially in internal partitions, e.g. a 200mm wide column & 100mm thick brick wall. In such situations, an offset of 100mm will appear wherever an RC column adjoins brickwork resulting in a non-flush surface with many corners & returns. There will be greater difficulty in completing the architectural finishing works like plastering, skirting, architraves, etc.The offset of RC & brickwork creates more turns & corners More precise work required for turns & corners
13Additional treatment to joint between two different materials At the joint interface between different materials e.g. RC & brickwork, special treatment like metal lathing is required to ensure there is proper bond and to prevent cracking of plaster wall at the joint. The additional number of joints increase the time and cost of construction.Providing metal lath on each RC & brick jointConsequences in choice of external finishesBrick and RC Joints need additional treatment Bulged RC surface requires thick plasterScaffolding: More housekeeping & longer construction period Thick plaster: Possible waviness
14Common issues in conventional methods Scaffolding tieback holesTo carry out plastering, scaffolding is necessary. The tie back holes used for securing scaffolding can be patched and re-painted only after the scaffold is dismantled. This is to be carried out via gondolas. Due to the different stages of operation, patchiness or uneven finishing on the surface is inevitable on the external wall surfaces.Scaffolding tie-back holes on façade plasteringPossible cracks & hollow plasteringDepending on the background substrate, plastering operations are usually 2 or 3 coats work & may compromise a spatter-dash, base or scratch coat & final skim-coat. Proper curing is also required between coats. This affects the overall progress. Besides, if the plaster thickness exceeds the allowable thickness, there is possibility of defects like cracks & hollowness appearing on the surface due to shrinkage of mortar.Surface cracks & hollowness appear when plaster is too thick
15More housekeeping is required for scaffolding & wet trades. Additional waterproofing treatment on jointsFor external surface at RC & brick joints, besides laying metal lath, a layer of waterproofing treatment is required to ensure water tightness. Failure to execute these measures properly may result in defects such as cracks & seepages. All these measures are needed to ensure quality in construction & will add to construction time & cost.External joints require waterproofing treatment Potential water seepage if joints are not treated properlyHousekeeping & longer construction periodScaffolding & wet trades like brickwork & plastering evidently require more housekeeping effort. More time is required to erect & dismantle scaffolding. This may hinder other concurrent activities & lead to longer construction period.More housekeeping is required for scaffolding & wet trades.Although adopting conventional methods and materials may lead to lower construction costs in some cases, the majority of wet trades pose inherent difficulties in achieving quality construction compared to buildable dry construction. In its place, good buildable design systems that facilitate ease of construction, depend less on-site labour, improve productivity & quality should be considered.
17How is it beneficial?The environment friendly building materials are composed of renewable, rather than non-renewable resources. These materials are environmentally viable as their impacts are considered over the life of the material. Use of these materials provides the following benefits.Resource Efficiency - benefits like high recycled content, naturally available, efficient manufacturing processes, locally available, high salvage potential, reusable and highly durable.2. Indoor Air Quality - Selection of the materials with benefits like low/ non-toxic, minimum emissions, low VOC content, moisture resistant and healthfully maintained.3. Energy Efficiency - Selection of the materials with benefits like reduction in energy consumption in buildings and facilities etc. Further elaborated in Energy related EBGH.4. Water conservation - Selection of materials with benefits like reduction in water use in buildings and conserve water in landscape areas. Further elaborated in Water related EBGH.5. Affordability - Is considered to compare the eco-friendly building materials to conventional materials within a defined percentage of the overall budget of the building.Apart from the above benefits, using these materials have the following advantages Have similar or low price compared to conventional building materials when total life cycle cost is assessed Do not exhaust the existing supplies of finite materials Save energy and reduce harmful emissions Helps in reducing environmental degradation Encouraged by building promotion council, so planning/ building permissions are easy to get Since they are less harmful to occupants, they make healthier and safer buildings
18Sustainable material options for conventional Building Materials Sr.NoConventional MaterialSustainable Alternative Material01Cement / ConcreteFly ash lightweight aerated concrete blocksPre-cast hollow concrete blocksPre-cast concrete blocksPrecise aerated cellular concrete walling blocks & roofing slabs02MetalsSteel with verified recycled contentAluminum with verified recycled contentScrap / salvaged steel & aluminum sectionsAntique iron & brass fixtures03Masonry UnitsFly ash lime gypsum products (bricks, aerated concrete blocks, stabilized mud blocks)Pre-cast materials (stone blocks, concrete blocks, hollow concrete blocks, cellular concrete units)Stabilized compressed earth blocks04Mortar & plastersLime, pozzolanic materials, rice husk ash to replace part of cement inn cement based mortarsFly ash (replacing 25% of cement)05WoodMedium density fiber boardsParticle boardsRice husk boardsCement bounded composite panels06PlasticsRecycled plastic panels
19Sustainable material options for conventional Building Materials Contd… 07GlassRecycled content glass (fiber glass, glass wool)High performance glazing08Finishes (Walls & ceilings)Gypsum plaster boardsCeramic tiles09Finishes (Flooring)Terrazzo (crushed stone, glass, flinters, etc)10Finishes (Paints)Water based paints & acrylics (Low VOC)11Finishes (Sealants & adhesives)Sealants: Acrylics / Silicones / Siliconized acrylicsAdhesives: Acrylics / phenol resins12Finishes (Furnishings)Recycled content materials (steel, glass, solid wood)Powder coated finishes for metalsWater based finishes like EOC varnishes for wooden components13Doors & WindowsNatural fiber reinforced polymer composite panelsUPVC / PVC panels
20Advantages of Sustainable building materials used in various construction phases Sr.NoAlternative MaterialAdvantagesStructural Materials01Pozzolanic materialsUpto 35% of flyash can directly be substituted for cement as blending materialSaves energy upto 20%Superior microstructure leading to lower permeabilityHigher electrical resistance leading to lesser chances of reinforcement corrosion02Flyash for concrete & mortarSubstitutes stone chips in concrete reducing dead weightPromotes fuel efficiency & carbon in ash provides sufficient heatPossess 28-day comprehensive strengths of the order of 40 MN/m2 & densities 1100 to 1800 kg/m3Better thermal & acoustic insulation & high fire resistance03Ferro cement & precast componentsAre 85% recyclable & energy efficientNo plastering required on inner side & no curing requiredSaves reinforcement & stronger than cast-in-citu structuresHigh fire resistance & better insulation04Precast RCC & Ferro cement framesAre 1/3rd in cost compared to 2nd grade timberHigher strength to weight ration than RCC20% saving on material costSuitable for precasting, flexible in cutting, drilling & jointing05Recycled steel sectionsCan be made entirely of recycled scrap ironHigh strength & non combustibleAvailable forms permit efficient & uniform applicationResistant to weathering, erosion & termite infestation06Ready Mix concreteWater reducer & workability enhancerHigh strength, resistance to thermal cracking & durableQuantities & ratios of mix managed betterLittle wastage & less man power required
21Advantages of Sustainable building materials used in various construction phases Contd… Sr.NoAlternative MaterialAdvantagesBricks & Blocks01Flyash sand-lime bricks / blocksAvailable in several load bearing gradesSaves in mortar plasteringLow water absorption, only sprinkling of water sufficient20-30% less thermal conductivity than concrete blocksHigh compressive strength than clay bricks02Flyash lime gypsum bricksGive highest strength among various bricksMost suitable for mechanized operationsFine finish & energy efficientLower requirement of mortar in construction03Aerated light weight concrete blocksReduces dead loads on super structureRaw material contains 70% recycled power plant wasteGood thermal insulation (upto 26% power savings)Requires very less water in constructionManufacturing process is 100% recyclable04Flyash cellular lightweight concrete blocksSubstitutes stone chips in concrete, reduces dead weightHas a density of app. 1/5th of concreteAre substitutes for conventional bricks & concrete blocks with densities from 800 kg/m3 to 1800 kg/m305Building blocks from mine & industrial wasteUtilizes waste from mining (iron ore) industriesReduces air, water & land pollutionIs energy efficient & cost effective06Stabilized compressed earth blocksHighly suitable for speedy & mortar less constructionCan be used for all application of burnt clay bricksAre sun dried & use cement for gaining required strength
22Advantages of Sustainable building materials used in various construction phases Contd… Sr.NoAlternative MaterialAdvantagesPlasters01Fibre reinforced clay plasterReduce plastic shrinkage & permeabilityPlant fibres act as reinforcement & controls crackingProvide increased impact & abrasion resistance02Phospho gypsum plasterWaste utilization prevents water & soil pollutionIs energy efficient & cost effectiveHas a very high setting time & comprehensive strength03Calcium silicate plasterAre economic, produces less wasteSmart finish & less energy consumingNon-emission of VOC & other toxic fumesNo skilled manpower required, durable & less water consumptionRoofingMicro concrete roofing tilesHighly cost effective, durable & lighter than other tilesValidated & certified by BMTPC (Building Materials & Technology Promotion council0Easily installed, colored to interest & reduce heat gainClay tilesUniform in size & more durableCost effective, fire resistant & energy efficientLow self weight, reduces loading on super structureBamboo matt corrugated sheetsResistant to water, fire, decay, termites etcLight, possess high resilience & better thermal comfortBearing strength comparable with GI sheet, ACCS etc.
23Advantages of Sustainable building materials used in various construction phases Contd… Sr.NoAlternative MaterialAdvantagesFlooring01Terrazzo / Marble mosaic flooringMade using waste & recycled materialForms a good waterproofing layer on exposed surfacesIs very cost effective02Phospho gypsum tilesManufactured from waste gypsumLight, fire resistant & good acoustic effects03Bamboo board flooringGood alternative to wooden flooringIs tough, easy to install & water resistantCost effectiveWood SubstitutesSalvaged woodUse of waste / recyclable timberCan be reused by converting into chips / particles for particle boardsRecycled laminated boardsUse of recycled waste (toothpaste containers)Sound proof, termite resistant & expansion resistantBamboo matt boards & veneer compositesEconomical compared to bamboo matt board for thickness more than 6mmHigher strength than veneer plywoodSuperior physical, mechanical properties compared to bamboo matt board04Fibre reinforced polymer boardsMade from plastic components, low installed & maintenance costsLight in weight, high strengthGood resistance to weathering & fire05Flyash jute polymer compositesCost effective as compared to conventional materialsStronger, more durable & resistant to corrosionDeveloped using Flyash as filler & jute cloth as reinforcement
24Advantages of Sustainable building materials used in various construction phases Contd… Sr.NoAlternative MaterialAdvantagesBoards & Panels01Calcinated Phospho gypsum wall panelsDurable, cost effective, water & pest resistantSmooth, easy installation & no need of plasteringAbility to take add-on’s like wall paper, decorative laminates, painting etc…Take paint directly, is fire resistant & easy laying of electrical conduits02Fibre Flyash cement boardsMade of recyclable materials like Flyash, agro waste etcAre stronger & more cost effectiveUsed for roofing, partitions & panels03Gypsum Plaster boardsLight weight, fire resistant & good thermal & sound propertiesUsed as lightweight partition panels, false ceiling lining, decoration paneling, boxing, cladding etc…04Composite door shuttersLow water absorption value (6-7%)Density nearly 50% of timber shuttersEasy installation & maintenanceCan be painted, polished or laminatedPaintsCement PaintsHas very low VOC (Volatile Organic Compounds)Easy to apply & highly economicHas good water resistant propertiesHas good covering capacity, easy mixing character, better resistance to crazing & microbial growthWater based compoundsHave same performance and durability as conventional solvent based paintsHas very low VOCHave no cost variations compared to conventional onesSealants & AdhesivesWaste based compoundsEpoxy resinsAre eco-friendly, consume lower energies during their life cyclesEasily disposable or recyclableLower occupational hazards & emission levelsInitial cost high but justified by overall life cycle performance