Low Cost Housing Concept

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Low Cost Housing Concept Or Economic Building ConceptDr K M SoniChief Engineer, WZ-I, CPWD, Mumbai

DefinitionIt is considered a concept of reduction in the cost of construction without sacrificing the strength required for the performance of the building.2

Conceptit is said that it is a misconception that low cost housing is based on inferior specifications, low quality and produces sub standard work. It is said that it is a misconception that low cost housing is only for the poor.3

Low cost housingFor low height structures ?For low income group ?For publicEven for government housingFor simple structures ?For rural housing?Or For all type of structures?4

Value EngineeringValue engineering also adopts methods of adopting design, materials and labour just suitable for the structure and achieving economy in overall construction.5

Acceptance of low cost housing conceptlow housing concept has still not been accepted by majority of architects and engineers.Possible reasons:Simple (architectural features make it costly)Low specifications (rich specifications make it costly)Low acceptability among middle income group and high income group people

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Discussion on low cost housingDeliberated only during financial recession.Budget is the main constraintBudget, a constraint to whom? 7

ExamplesWhen mass housing is required and financial resources are limited like Indira Awas Yojana or similar other schemes.When mass housing schemes are required after natural disasters, particularly due to limited time and funds available for construction.When recession is there and lower middle class finds difficult to purchase the flats due to their financial constraints.

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Commonalitiescommon in all above situations is financial constraintfor poor or lower middle class people.(may not be acceptable to many engineers who are believers of low cost housing but is a reality.)Why dont we talk about low cost Metro, low cost flyovers, low cost bridges, low cost airports etc. 9

InferenceLow cost housing reflects that it is the housing of low cost and though it may have nothing to do for whom the housing is made but general concept is that low cost housing is for poor and it is very difficult to change the existing concept. Some of the engineers and administrators have started calling it as affordable housing which is again for them who cannot afford a good house at a higher cost.10

So, one way is let us accept it that low cost housing is for the poor masses and develop design and specifications accordingly and for general housing deliberate on economic housing.Or go on calling low cost housing as a misconcept that it is for poor masses only. 11

Common methods adopted in low cost housing as per available literature12

Reduce the type and depth of foundationDepth anywhere from 50 to 60 cms for isolated footingsProvide isolated footings in place of raft foundationProvide raft foundation in place of pile foundationHighly non technical ideasPlease do not try without proper evaluation13

Reduce the wall thickness From 230 mm to 150 mmAdopted in unauthorised and non engineered construction for load bearing constructionAdopted by some private builders in framed construction for all internal and external wallsNon technical ideaCan not be adopted due to technical, maintenance, comfort considerations14

Reduce the plinth heightIn few years the road level comes at par with plinth level and plinth disappears. Non technical ideaHas many functional problems 15

Use of mud/soil stabilised blocksMay have @ 5% cementCan be used after the economy is established16

Use of some other materialsMudThatchStoneFrameless doorsMud plasterLow cost housing in such case will need to be divided further in rural and urban low cost housing17

Use of hollow cement concrete blocksSubstitute of clay bricksEconomics depend upon local availabilityIf the economy is established, they can be used18

Use of wood substitutesDepends upon availability and type of wood and substituted materialsWood substitutes are now largely adopted in all type of construction19

Use of pre cast slabs/jack arch roofingNot suggested for earthquake prone areasEconomy depends on local availability of materials and labour20

Use of single stack system, reduction of traps, low width shafts etc.Not advisable considering maintainability.Maintenance difficult.

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Use precast lintels or brick arch lintelsPlease do not try in earthquake regionSaves cost if bricks are locally/economically available while cement/concrete are not available locally and are costly22

Plinth area of building Reduce the area of the unit or its components23

Use of locally available materialsBest way of economy in terms of materials, labour, transport and even management.24

Statement of Laurie Baker (1975)All the building materials should be found within five miles of the site.Low cost techniques should not be considered only for the poorour aim should be to design simplest of buildings for all 25

SpecificationsSpecifications play an important role in deciding the cost of housing. Interior and finishing works may have a large variation in cost depending upon the specifications adopted. For example if in Chennai, sand stone cladding, marble flooring, are provided and in Delhi, granite flooring and textured coating are provided. Some of the occupants tend to alter specifications even before they occupy the house on their own and some after looking to their neighbours.26

Reduction in costReduction in cost is possible by sacrificing something.AestheticUniquenessDurabilityFunctionmaintainability 27

Architectural features and designArchitectural features added in a building may not be required from any other consideration but will add to the cost and may not fit to low cost housing conceptDesign of various components may not be optimum as per the requirements

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Design Economic designFuture considerations29

Life cycle costsIt is a mistake to define a low cost house based on initial cost of construction without giving any consideration of maintenance or life cycle of the structure. 30

Factors to be considered for economic housing31

Use of locally available materials Base price is lowTransportation cost is lowLocal workers know their use and fixing/ installation hence economicSaves the time

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Make use of traditional methodsTraditional methods are time testedTraditional methods are economicTraditional methods are based on local materials Local workers have the knowledge of using Traditional methods 33

Use of free natural resourcesAirLightTo minimize cost of initial construction and thereafter maintenance cost34

Reduction in labour cost Through use of local materialsThrough use of local techniquesThrough use of more skilled labourThrough use of small toolsThrough mechanization 35

Reduction in time of construction Better planningThrough use of small toolsThrough mechanizationQuality constructionBetter managementReduction in wastage36

Reduction in transport, handling and storage costUse of local materialsBy following Just in time approach forMaterialsAvoid storage, multiple handling, storage, wastage, theft, dead stock Close co-ordinationUse of prefabricated/precast members 37

Reduction in wastageAdoption of Total Quality Management policyBetter planningBetter executionBetter management of resources by following just in time approach38

Plan for reduction in maintenance costReduce life cycle costsPlan for natural lightingPlan for use of other natural benefits 39

Management of men, materials, machinery and moneyManagement of money, machinery and materialsManagement of workersManagement of managers40

Basis of economicsUse of economies of scaleReduce fixed costsConvert some of the Fixed costs to semi variable costs Horizontal expansion of the associated activities with marketing strategies

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Low quality conceptcost of low quality of work and low quality architects, structural designers, and contractors including skilled workers will also lead to cost reduction. In fact, these cost reductions are misconcepts of economy particularly to the house considering its life cycle, to the society and the nation but adopted widely.

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Fair wayEconomy in construction can be achieved by management of men, materials, money and machinery and adopting locally available materials and techniques with the concepts of economics and total quality management. 43

ConclusionsLow cost housing is considered housing constructed with low budget. The definition should have been the housing with minimum cost even if budget is available. Thus concept should then be valid for small or big, single or multistoried and EWS or bungalow construction and all type of construction.

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