International Journal of Engineering & Technology IJET-IJENS Vol:14 No:01 108 147801-6565-IJET-IJENS © February 2014 IJENS I J E N S Appraisal of Timber as Structural Members for Residential Buildings in Nigeria Anthony Nkem Ede (PhD) and Joshua Omoruyi Okundaye Department of Civil Engineering, College of Science and Technology, Covenant University, Canaan Land, KM 10, Idiroko Road, P.M.B. 1023 Ota, Ogun state, Nigeria Phone +234-8060-164-058 anthony.ede@covenantuniversity.edu.ng Abstract - Concrete and sand crate blocks are the most common construction materials adopted for residential buildings in Nigeria. They are used in the form of reinforced concrete frames and sand crate block walls. These heavy weight materials are mostly assembled on site by bricklayers or masons. The high demand for these construction materials and the intensive labour required for site placement have led to high cost of these materials and consequently to general high cost of construction in Nigeria. These facts contribute to making the access to good housing by common man very difficult. It therefore becomes very obvious that alternative means of construction should be explored and implemented in order for the average and below average Nigerian citizen to have a decent roof over their heads. Based on the rapid advances in the construction materials technology over the recent years, civil engineers have been enabled to produce new solutions of built structures to serve the common needs of society. In that line, this research work seeks to provide an alternative solution in timber as a load bearing member for affordable residential buildings in Nigeria. A case study of 5-bedroom duplex is presented. A concrete design with Orion R16 software and a manual timber design are produced for the building with the corresponding bill of quantities. The comparative studies show that the application of timber as a structural members will help to drive down the cost of residential buildings in Nigeria and make them affordable to common man. Index Term- Timber, Concrete, Structural Elements, Affordable Homes. 1. INTRODUCTION The technological advancement of every age has a lot to do with the quality of materials available for that age. As the world has transited through the primitive age to the Stone Age, through industrial age into the current information/knowledge worker age, so have the dominant construction materials changed through the ages from earth to wood, to stone to concrete, to steel to FRP composites etc. Although the traditional materials continue to be in use over successive ages, the technological advancement made in every new age depends most on how these materials are combined to the advantage of the society in terms of safety, economy and functionality of built structures. In the last 200 years, rapid advances in construction materials technology have enabled civil engineers to achieve impressive gains in the safety, economy, and functionality of structures built to serve the common needs of society. Through such gains, the health and standard of living of the members of the society have greatly improved. Generally, the provision of affordable housing for low income workers in developing countries has become a cause for concern for Governments. This problem is very acute in the urban areas with the continuous drift of the masses from the rural areas to the urbanized areas in search of greener pasture. Nigeria has the largest population and is the second largest economy in Africa [1]. With an estimated population of about 170 million, population growth rate of about 2.55%, GDP growth of 6.81% and annual urbanization rate of change of 3.5%, the nation is in dare need of affordable homes for the teaming population. As one of the fastest growing economies in the world, it is saddled with so many on-going projects, both technological and infrastructural, executed by Governments and by the private sector, in the form of small scale and large scale projects, all competing to meet up with the high demand created by the nation’s large population and the high rate of rural-urban migration. Not minding all the efforts that have been put in place and the massive urbanization taking place, the ultimate goal of making affordable houses available for the masses remain mirage due to high cost of building materials. This high cost of building materials have been severally confirmed by many researchers as the leading cause of sharp practices that have been responsible for the frequent building collapse that occurs in Nigeria [2], [3]. It must be known that over 95% cases of collapsed building structures verified in Nigeria over the years involved concrete and sand crate block structures. This must not be unconnected to the limited ductile behaviour of sand crate blocks which very often are exposed to absorbing excessive loads. The vast variation of the properties of concrete is another great problem to contend with. Every proportion of the components of concrete including the aggregate size has an enormous effect on the quality such that the general compressive strength is very easily compromised [4]. Faced with the escalating cost of conventional building materials, most often imported into the country with hard earned foreign exchange, there is urgent need to explore new idea that seeks to encourage the adoption locally available building materials which will lead to cheaper rural and urban structures accessible to the masses. The good news is that the nation is highly blessed with abundant timber which has not been maximally utilized to the nation’s advantage. Nigeria is highly enriched with a surplus supply of timber, with various species of trees that are suitable for construction. The locally- grown timber for building construction can be easily obtained from the available sawmills. This method of construction also