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Building defect is one of the major components of building problems that significantly needed attention. When a building fails to function as it should, we must immediately seek for the determination. Is the problem taking place as the result of the worker's failure to assemble it properly? Is it involving the nature of it? Is the proper maintenance of the building not been performed as it should have been? The answers often depend upon a number of factors: the age of the affected building components, the exact nature of the problem, the presence or absence of human error, or some combination of all those three. This paper will review and discuss some of the major building defects happen throughout the world. It contains some of the main concepts and the definition of the terminological terms used. In addition, the causes, symptoms and remedial work of defect also been discussed in this paper.

Lime is among the binding agents used in binding masonry units, such as brick, in many historical buildings around the world. Its physical strength, mechanical strength, and durability properties, as well as its raw material composition, can play substantial roles in the structural behavior of historic buildings. The production technologies may also differ according to their specific use in the structural layout. Hence, the characteristics of lime mortars are of interest in the assessment of the structural characteristics of historic buildings. In addition, the determination of characteristics of lime mortars is also important for the production of intervention mortars to be used in the restoration of historic buildings. This research focused on the effects of egg white on lime mortar's physical and mechanical properties. Five mixes were prepared by maintaining a constant lime-sand-water ratio of 1:2:0.035. As the binder material, the control mixture comprised only lime putty, while various percentages of egg white in the range of 2-10% were used to prepare the remaining mixtures. An experiment was then performed with different percentages of egg white to examine the lime mortar's axial compressive and flexural strength, as well as the water absorption. The results indicated that the compressive and flexural strength of the lime mortar increased with the increasing percentage of egg white added into lime mortar until the mixture reached 6% egg white. The addition of 8% and 10% egg white made the compressive and flexural strength start to decrease. Lime mortar that contains 6% egg white had the highest compressive and flexural strength compared to the other mix design groups. The axial compressive strength and bending strength of lime mortar can also be influenced by the air pores.

Nowadays, the utilization of Oil Palm Shell (OPS) as lightweight aggregate in concrete especially in the structure application has become prevalent. As an industrial waste product, Oil Palm Shell (OPS) possibly will be the alternative material to be employed in the construction industry. With its advantage as heat resistant material, this study will focus on the potential of OPS as lightweight aggregate with regard to the optimum content of OPS for thermal insulating material. A total of 15 mixes were prepared and tested with 3 different cement/sand ratios (1.7, 1.8, 1.9) and 5 different cement contents (300, 350, 400, 450, 500 kg/m³). The result of this study show that the highest sand used will produced good workability but increased thermal conductivity of mix value. The test result indicates that the thermal conductivity and insulation criterion is substantially improved with the volume use of OPS and strong relationship between thermal conductivity and unit weight is obtained. The measured thermal conductivity value range from 0.54W/mC to 1.1 W/mC. The ideal value for semi structure insulation material establish by RILEM only  achieve for mix that used cement content 400 kg/m³ and below, which thermal conductivity is 0.75 W/mC below.

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This paper presents the effects of agricultural wastes on the mechanical properties of lightweight foamed concrete, LFC. The agricultural wastes utilized in this research are banana skin powder (BSP) and palm oil fuel ash (POFA) as cement and sand replacement, respectively. Physical and chemical tests were conducted to determine the chemical composition and particle size of both BSP and POFA. These chemical and physical properties of the raw materials are important in understanding the effects they have on the mechanical properties of lightweight foamed concrete incorporating BSP and POFA, which is designated as LFC-BSP-POFA. Cube, cylindrical, and prism specimens of LFC-BSP-POFA with density of 1800kg/m³ were cast and tested to determine its compressive strength, tensile strength, modulus of elasticity and flexural strength. Twelve (12) LFC-BSP-POFA mixtures were prepared with content of BSP as cement replacement of 0%, 0.2%, 0.4%, 0.6%, 0.8% and 1% by weight. For each mixture, the content of POFA as sand replacement are 0% and 15%. It was found that BSP and POFA each contain 55.98% and 51.83% silicon dioxide, and 2.71% and 2.32% aluminum oxide, respectively. The particle size for these two materials as obtained from PSA test showed that both materials are considered as fine particles, which is within 0.1µm to 250 µm. These chemical composition and particle size of BSP and POFA contribute to the pozzolanic reaction in LFC. This is proven by the results obtained from the mechanical properties tests which show that the incorporation of both BSP and POFA as cement and sand replacement have some significant effects on the mechanical properties of LFC. The increase percentage of BSP and POFA incorporated in LFC had shown slight increment in its mechanical properties.

This paper presents an investigation on lightweight foamed concrete (LFC) with different type of additives. LFC with 600, 1000 and 1400 kg/m3 density were cast and tested. Fly ash, lime and polypropylene fibre were used on each density with different percentages. All the additives effects were compared with normal LFC as control mix. Mechanical properties of LFC were evaluated with several tests up to 180 days. The results show that the drying shrinkage, compressive strength and flexural strength are affected by the hydration process of each additive in the harden LFC. Fly ash as pozzolanic material helps to strengthen the LFC, though it needs longer curing period to achieve ultimate strength. Lime gives slight contribution to strength as detail investigation on microstructure formation will give clear answer on how the mechanical properties were affected. The addition of polypropylene contributes to flexural strength and shrinkage of LFC. Polypropylene fibre only contributes to compressive strength at low LFC density.