8 — Supply Depot
8 — Refinery (Gas)
10 — Barracks
16 — Supply Depot
17-18 — 3rd Factory (Depending on resources and pressure)
@100% Factory: Train 2 Vultures
Vultures have to be on the map and lowering unit count. If you lose a single vulture or they aren't roaming around the map, you will lose to a push.
As Vultures are out on the map, start walling off your choke
@100% Vultures: Add 2 Machine Shops (Factory Add-ons), Get Second Gas and start Starport
@100% Add-ons: Research Spider Mines and Siege Mode, Make 3 more Vultures
Next 200 Gas start 2 tanks
@100% Starport: add an addon
4:00 Minute Mark — Build an Engineering Bay for detection and anti-air
From here on out, you expand up to 5 factories, and then get your 2nd Command Center.