In fact WCT in Delhi is VAT applicable in the case of work contracts, i.e. contracts involving material supply and activities of erection/commissioning/labour etc.
As per Delhi VAT, in the case of work contracts, tax is payable only on material portion. In case the proportion of material is not determinable, then a standard deduction for labour portion may be reduced from value of work contract and remaining amount is considered as material portion on which DVAT is payable. Like in the case of civil work contracts, there is a 20% deduction allowed for labour portion and hence DVAT is payable on 80% of the work contract value if the material value can not be identified with accuracy separately.