Hello Paul,
I looked up some reports (based on research) that demonstrate an increase in productivity when employees are allowed to work from home. This one makes an interesting conclusion:
” We report the results of a WFH experiment at Ctrip, a 16,000-employee, NASDAQ-listed Chinese travel agency. Call center employees who volunteered to WFH were randomly assigned either to work from home or in the office for nine months. Home working led to a 13% performance increase, of which 9% was from working more minutes per shift (fewer breaks and sick days) and 4% from more calls per minute (attributed to a quieter and more convenient working environment). "
Source: http://qje.oxfordjournals.org/content/130/1/165.short