I have a field that represents the date that we will start (ProjectedInstallDate) work on a project. I have another text field with data brought over from a legacy program, call 'Install Time Required" the text in this feild is "1 Day", "2 Days", "3 Days", "4 Days", "5 Days", "6 Days"  etc...This data represent the estimated number of days it will take us to do the work.  I thought I could do a really simple formula like I pasted below to calculate the estimated finish date.... but I forgot that we don't work weekends.  What can I add to my formula to make the number of days only land on a weekday.

Data TypeFormula  
IF( xProject_InstallationTimeReq__c = "1 Days",xProject_ProjectedInstallDate__c + 1,
IF( xProject_InstallationTimeReq__c = "2 Days",xProject_ProjectedInstallDate__c + 2,
IF( xProject_InstallationTimeReq__c = "3 Days",xProject_ProjectedInstallDate__c + 3,
IF( xProject_InstallationTimeReq__c = "4 Days",xProject_ProjectedInstallDate__c + 4,
IF( xProject_InstallationTimeReq__c = "5 Days",xProject_ProjectedInstallDate__c + 5,
IF( xProject_InstallationTimeReq__c = "6 Days",xProject_ProjectedInstallDate__c + 6,
IF( xProject_InstallationTimeReq__c = "7 Days",xProject_ProjectedInstallDate__c + 7,
IF( xProject_InstallationTimeReq__c = "8 Days",xProject_ProjectedInstallDate__c + 8,
IF( xProject_InstallationTimeReq__c = "9 Days",xProject_ProjectedInstallDate__c + 9,
IF( xProject_InstallationTimeReq__c = "10 Days",xProject_ProjectedInstallDate__c + 10,
IF( xProject_InstallationTimeReq__c = "11 Days",xProject_ProjectedInstallDate__c + 11,
IF( xProject_InstallationTimeReq__c = "12 Days",xProject_ProjectedInstallDate__c + 12,
Null))))))))))))