Multi-building industrial parks need a builder who can phase site work, shells and tenant finish so that the first building is handed over while the last is still in foundations. That is the sequencing problem on the I-25 and E-470 side of Thornton, and we plan it as one logistics exercise: shared detention, shared utilities, one haul road and a delivery order that keeps the first tenant's occupancy date intact.
Recent park announcements show the scale. A trade report describes Crossroads 25 as a 76-acre, 1.1 million square foot, six-building industrial park at the northeast corner of I-25 and E-470 in Thornton, with phase one of 828,000 square feet scheduled for delivery in Q3 2027. A separate listing describes Rockefeller Group buying 35.6 acres at East 152nd Avenue and Washington Street in September 2023 for 25 Commerce Park, a three-building, 453,550 square foot project. We treat both as evidence of building types in demand, not as our own work.
For ecommerce fulfillment tenants the same corridor has already proven multi-level box construction. Amazon announced in June 2017 an 855,000 square foot, three-level fulfillment center (2.4 million square feet of floor area) near I-25 and 144th Avenue in Thornton with 1,500 full-time positions. Multi-level shells bring structural slabs, vertical conveyors and heavier fire-protection design, and we carry those scopes in preconstruction long before the structure is bid.
How we phase a park
We start with the master site plan and decide which infrastructure is built once and which is built per building. The detention basin, the main utility trunk lines, the internal truck loop and the grading for all buildings usually go in first, followed by the first building's foundations. Later buildings are released as tenants sign, and the common infrastructure is sized for the full build-out so that nothing needs to be dug up again.
Within each building, we control the slab pour order, panel erection and roof dry-in so that dock equipment, fire-protection and the tenant's racking can be installed while neighbors are still under construction. Our warehouse shell construction process puts the interior-finish contractors on a separate access gate and a dated release list.
Interstate and commuter-rail access
Interstate 25 passes through Thornton twice, E-470 runs through northern Thornton, and the E-470 interchange at Quebec Street in Thornton opened November 24, 2014. Those routes decide which tenant uses which parcel, and we use them to set haul plans for concrete trucks, steel and precast. We confirm the temporary traffic plan with the city before a building permit is issued.
RTD N Line commuter rail opened September 21, 2020 with three Thornton stations (Original Thornton/88th, Thornton Crossroads/104th, and Eastlake/124th, the northern terminus). The line matters to industrial owners because it affects the workforce commute to flex and light-industrial buildings, and it matters to us because transit corridors can add coordination with the railroad or the transit agency when work approaches the right-of-way.
Long-lead items on a speculative park
On a speculative building the schedule is driven by the long-lead list: transformers, switchgear, dock levelers, overhead doors, rooftop units and the fire pump. We keep a long-lead procurement register from the day of award and tie each item to a release date and an installation date.
If a tenant signs mid-construction and changes the clear height, the dock count or the power requirement, change control puts the cost and schedule effect in front of the owner before the modification is built. That prevents rework and makes the tenant's requirements visible.
What changes the price between parks
The cost drivers in a park are shared infrastructure, the building spec and the tenant improvements that follow. Shared infrastructure is priced once and allocated across buildings. The building spec is priced for the clear height, column spacing, dock ratio and the fire-protection design. Tenant improvements are priced as a separate scope that a tenant can adjust, so the owner is not carrying unknowns in the shell price.
We provide an industrial tenant improvement unit-price sheet when it helps, covering office buildouts, additional docks, extra power and mezzanines, so a leasing team can quote costs to a tenant quickly.
Aprons, courts and site concrete
Between buildings, the paving decides whether a park runs. We build dock aprons and loading zones in reinforced concrete sized for the landing-gear loads of parked trailers, with joints laid out away from the dolly pads, and truck courts sized for the turning radius of the internal loop. The subgrade is proof-rolled and tested before any concrete is placed.
The same crews handle curb and gutter, ADA ramps, sidewalks and the fire-lane paving that the fire marshal inspects. An owner with sites in both Thornton and Northglenn gets the same submittal format and quality plan on each project, while we confirm each city's adopted edition separately.
Code basis and permit reviews
As of January 20, 2026, the Home Builders Association of Metro Denver tracker lists Thornton as enforcing the 2024 IBC, IRC and IFC with the 2023 NEC, implemented July 6, 2025. That tracker is not an official source, so we confirm the edition and any local amendment with the city's building department before a permit set is finalized.
For tilt-up work, we pay particular attention to the structural review of panel connections and to fire-protection design for high-piled storage, where the rack configuration controls the sprinkler design. We reference the tilt-wall building design criteria in the first design meeting.
Share the master plan and the tenant list
Send the master plan, the tenant requirements and the delivery date you must hit. We will return a phasing plan with the shared infrastructure, the long-lead list and the code basis. Owners also look at Brighton for similar parcels.
Common Questions
Can you deliver the first building while the others are still under construction?
Yes, if the site infrastructure is sequenced for it. The first building needs its own access, utilities and fire lane that are separated from the construction zone. We plan that separation in preconstruction and have the city inspect the first building's site independently.
What does a multi-level fulfillment building add to the scope?
Structural slabs on the upper levels, vertical conveyance, a heavier structural frame, and a fire-protection design that handles stored commodities on multiple floors. We bring structural, fire protection and the operator's equipment vendor to the same table in preconstruction.
How should a tenant evaluate a spec building?
Check clear height, column spacing, dock ratio, power and the fire-protection design against your racking and throughput plan, and ask what can be changed before the shell is complete. We prepare a checklist for tenants that reflects those points.
Does commuter rail affect construction?
It can if your site is next to the right-of-way. Work near the line may require approvals, flagging and clearance, and the transit agency's requirements come into the schedule. We check the site's relationship to the corridor before the schedule is promised.