I-10 East Houston The I-10 East market contains approximately 130 office buildings in the submarket, comprising a total of 1,310,600 rentable square feet. With the vacancy traditionally around 12%, this is a good market for office building investors. Quoted rents are trending at $16 per square foot and are likely to increase over the coming years. I-10 East runs through Jacinto City and across the San Jacinto River. The I-10 East market has a very heavy industrial market.