You need completely separate home and business - including land allocation.
If the business part is value $1.400,000 (assuming the selling price allocated to the personal home is $100,000) - that amount should be considered as the price for new property.
100% of the proceeds from the sale of the investment property must be reinvested into a property of like-kind or greater value.
If the cost of the replacement property - let's say $1,000,000 - that means $1.000,000/$1.400,000*100%= 71.42% of the gain would be deferred, and 38,58% of the gain will be taxable.
You need to complete form 8824 - http://www.irs.gov/pub/irs-pdf/f8824.pdf - you would enter all information regarding the exchange and determine if any amounts should be transferred to Schedule D or Form 4797.
section 1031 lists following properties as not qualified - http://www4.law.cornell.edu/uscode/html/uscode26/usc_sec_26_00001031----000-.html
(A) stock in trade or other property held primarily for sale,
(B) stocks, bonds, or notes,
(C) other securities or evidences of indebtedness or interest,
(D) interests in a partnership,
(E) certificates of trust or beneficial interests, or
(F) choses in action.
In additional you should concern that replacement properties would be "like-kind" - see some discussion here - http://www.us1031.com/qualifiedproperties.htm
I would suggest to start with finding a Qualified Intermediary to facilitate the 1031 Exchange Transaction.