Allowable Wastage of Construction Materials

Construction wastes are usually encountered in construction works. There are many things that bring about the wastage of materials in construction sites. These may include:

i. Frequent design and client’s changes;

ii. Rework due to worker’s mistakes;

iii.  Poor contract documents;

iv. Wrong and lack of storage of materials;

v. Poor strategy for waste minimization;

vi. Shortage and lack of skilled workers;

vii. Poor site conditions;

viii. Damage during transportation;

ix. Theft and vandalism;

x. Mistakes in quantity surveying and allowances.

Wastes in construction industries affect the economy of a nation and have adverse environmental impacts. Efforts should be made to minimize waste. Since wastes are inevitable, certain percentage allowances are made for wastes for different construction materials. Table 1 shows common construction materials and pre-contract waste allowances for the Nigerian construction industry. Those engaged in quantity estimation would find it useful.

Table 1:Allowable Wastage of Construction Materials