AS companies scramble to pre-commit to newly constructed office space coming online in the next few years, the reality of the commercial office market is forcing many to take a somewhat piecemeal approach to securing tenancies. Rio Tinto Iron Ore and its subsidiaries are currently spread over at least six sites in Perth’s CBD. Rio’s most recent acquisition is three floors of a newly refurbished building at 110 William Street, which has been occupied by subsidiary Pilbara Iron. The company has secured 934 square metres of space, but was unable to occupy the full five floors of the building due to pre-existing office tenants. The site is opposite the new Wesley Centre at 95 William Street, where Rio has signed on to take the full 13,000sqm of space, due to be completed later this year. At present, the company is occupying offices in Central Park and other William St sites, and has spread across to two locations on Mill St. About 6,200sqm are occupied at 1 Mill St, while further down at number 5, Rio has a smaller parcel of 1,800sqm. It also has 1,970sqm at 40 The Esplanade. WA Business News understands Rio is in the process of signing several new sites, although agreements are yet to be finalised. In addition to the Wesley Centre, the only other substantial site Rio has committed to is a two hectare area at Perth Airport, which the company announced in December. Rio plans to build a remote operations centre on the land, which it has leased for 10 years. The centre, which will accommodate more than 320 staff, will include a purpose-built operational control room and an office block. While Rio is exploring its options at sites throughout the CBD, BHP Billiton is consolidating its presence, having committed to 40,000sqm at the planned City Square office tower. However, the opportunity for Rio to secure a similar sized area is limited, with much of the new supply due to come online in the next few years already pre-committed.