See
http://www.irs.gov/Businesses/Small-Businesses-&-Self-Employed/Home-Office-Deduction and links therein for more details, but this might be applicable:
If you are an employee and you use a part of your home for business, you may qualify for a deduction for its business use. You must meet the tests discussed above plus:
Your business use must be for the convenience of your employer, and
You must not rent any part of your home to your employer and use the rented portion to perform services as an employee for that employer.
If the use of the home office is merely appropriate and helpful, you cannot deduct expenses for the business use of your home.
