The leasing footprint of San Diego life sciences companies grew by nearly 1.1 million net square feet in 2016, according to a year-end report from brokerage firm JLL.

That increase topped those recorded in 2015 and in 2014, when the space occupied by companies in that market sector rose by nearly 947,000 and about 877,500, respectively.

JLL reported 65 transactions for about 1.5 million square feet of gross leasing activity during 2016 in San Diego, a 16 percent increase compared with the region’s five-year average.

Compared with 2015, when 1.7 million was leased through 62 transactions, gross leasing activity in San Diego was down nearly 10 percent, but the number of leases signed rose about 5 percent, JLL said.

Of the lease transactions, 77 percent were completed by companies that were moving or expanding; 23 percent were renewals, the firm said.

More than a fifth of gross leasing activity in San Diego in 2016 was by medtech giant Illumina Inc., which signed a lease for 316,000 square feet to accommodate growth. The lease pushed its portfolio of local real estate to more than one million square feet, according to JLL.

To take advantage of companies’ growth, the local inventory of life science buildings has grown, rising by 10 percent since 2014 with the addition of 1.4 million square feet of new space, the firm reported.

However, that only juiced the availability rate by 1.7 in 2016, compared with 2014, according to JLL.

Availability is likely to remain limited in 2017, especially for “Class A” campuses, which generally offer amenities as well as new office space, the firm said.