In case of a construction sector the rule for Service Tax
applies as follows:
1) If its a commercial complex - Service Tax is applicable
2) If its a Residential complex - Service Tax will not be
applicable (provided there should not be more than 8 flats)
The calculation should be as follows:

1/3 of the work value alone is taxable @ 12.36 %

If the work value is 12.00 lacs - 4.00 lacs is turnover for
service tax.

Important note: Since 1/3 alone chargeable for tax no input
credit is allowed.

If the major materials viz., steel/cement is supplied by the
client the work value has to be derived after deducting the
above costs

service tax is applicable in both conditions

Service tax is aplicabel only on commercial construction 
but the residentel constrction was exempted from 29th 
jan.2009 vid circular no.108/02/2009-st issued by central 
board of excise and customs. and the Service tax Rate now 
is 10.3%