It is very important to time the start of the construction.Start excavation and fixing of the main door in : 
 
 

Chaitra (March-April)  -will bring financial loss Vaishaka (April-May)  -very auspicious Jaistha (May-June)  -death and unhappiness Shraavana (July-Aug.) -a healthy family Bhaadrapada (Aug-Sept.) -disease in the family Ashwayuja (Sept. –Octo) - family feuds and enmity Kaarthika (Octo- Nov) -will attract wealth Maargashira(Nov –Dec) -troubles in fears in daily life Pushya(Dec-Jan)  -destructive fires and troubles Maagha (Jan-Feb)  -good family life Phaalguna(Feb –Mar)  -will gain wealth and fame

Further  Mondays,Wednesdays, Thursdays and Fridays are auscpicious