Property group Downing has let the entire fourth floor at Victoria House in Liverpool city centre.
BAM Construction has taken 3,073 sq ft at the building on James Street on a short-term, flexible lease for an undisclosed rent.
The company will be based there while it is progressing works on the Mann Island development by Neptune and Countryside.
Downing will also provide BAM with 15 on-site car parking spaces and the rent includes service charge and building insurance.
Robin Ellis, senior agency surveyor at Downing, said: "This part of the city centre has seen huge changes in recent months with new businesses, restaurants and hotels locating to the area, as well as the on-going development of the Mann Island scheme. These developments are another piece in the jigsaw of city connectivity and Victoria House is right at the heart of this.
"That BAM could move in quickly on a flexible deal that gives them certainty on occupational costs other than rent, was certainly a selling point for them."
Downing said there is strong interest in the ground floor retail unit, with talks with a national operator progressing, along with its refurbished office suites at Victoria House.
Mason Owen and CBRE are joint agents on Victoria House. BAM was not represented in negotiations.