Gate 3 — Design Options

Gate 3 generates three distinct architectural concept options based on the confirmed programme and site context. Each option represents a different strategic approach to organising the building — different massing strategies, circulation typologies, and spatial hierarchies.

What Gate 3 does

1. Generates three options — each with a distinct organisational strategy and spatial narrative
2. Produces massing diagrams — 2D block plan and section sketch per option
3. Scores each option — against the brief criteria, site constraints, and programme efficiency
4. Writes a rationale — explains the design thinking behind each option in plain language
5. Identifies trade-offs — for each option, what it does well and what it sacrifices

The three options

Options are generated to be genuinely different — not three similar solutions with minor variations. Typical contrasts include:

Axis	Option A example	Option B example	Option C example
Massing	Perimeter block	Point tower + podium	Linear slab
Circulation	Central atrium	Dual-stair cores	External gallery access
Ground floor	Retail activation	Residential gardens	Mixed active / residential
Orientation	South-facing courts	Split E/W aspects	North-south finger plan

Option summary card

Each option shows:

• Name — e.g. "Option A — Perimeter Courtyard"
• Massing diagram — schematic block plan (north-oriented SVG)
• Section sketch — indicative section showing heights and levels
• Key statistics: GIA, NIA efficiency, units per floor, car parking implication, approximate height
• Score — overall rating against the brief (Quality / Cost / Regulatory / Technical)
• Strengths — what the option does well
• Trade-offs — what the option sacrifices or makes harder

Selecting an option

Review all three options and:

1. Click Select on your preferred option
2. Optionally, add a note explaining why: "Option B preferred — client wants visible landmark tower and ground activation"
3. Optionally, request a hybrid: "Combine Option A's courtyard with Option B's ground floor retail strategy"

The selected option (or hybrid) is locked in and Gate 4 begins.

Requesting a hybrid

If you want elements from more than one option:

Use Option A's perimeter courtyard massing but add Option B's ground
floor retail activation on the south frontage

Purple8 generates a Hybrid Option and presents it for your approval before proceeding.

What if none of the options work?

If all three options miss the mark:

None of these work — the brief requires basement car parking which none of the
options have addressed. Please regenerate with basement parking as a fixed constraint.

Gate 3 re-runs with the additional constraint. You can provide as many corrections as needed — Gate 3 will regenerate until you have an option you want to take forward.