Programming and planning a building
A programme (or brief) is the written list of what a building must do. It answers four questions.
- Who will use it: a family, children, patients, shoppers?
- What will they do: sleep, learn, treat, sell? Each job needs a room.
- How much: floor area for each room and the money available.
- Which rules: building codes, fire exits, height limits.
Two numbers help to check a plot. Building coverage ratio = footprint ÷ plot area × 100. Floor area ratio (FAR) = total floor area of all floors ÷ plot area.
Detached houses
A detached house is one home on its own plot, with open space on all sides.
- Good: privacy, light and air on every side, a garden, freedom to extend later.
- Not so good: needs a lot of land, long pipes and roads per family, costs more per home.
Planning points: put living rooms to catch daylight, keep the kitchen near the entrance and the service area, place bedrooms in a quiet corner, and keep space for parking and a garden within the allowed coverage.
Apartment buildings
An apartment building (block of flats) puts many homes in one building. Walls, floors, stairs, lifts and pipes are shared.
- Good: less land per family, shared lifts and security, lower cost per home.
- Not so good: less privacy, noise through walls, fewer chances to change your home.
Flats are reached by a corridor (many homes per floor) or a stair core (few homes around one stair). Every flat needs daylight, a safe fire escape, and a lift in taller blocks. Because floors are stacked, FAR is high.
Various building types
Every building type has its own special needs.
- School: bright classrooms (windows with soft daylight), safe wide exits, playground, separate toilets.
- Hospital: wide corridors for beds, clean and dirty flows kept apart, quiet wards, easy ambulance entry.
- Shop: visible front, easy entry, a back room for stock, safe exits.
- Office: flexible open floors, meeting rooms, lifts and good lighting.
Good planners place rooms by how they connect: which rooms must be close, and which must be far apart.
Barrier-free and universal design
A barrier is anything that stops someone from using a place: a step for a wheelchair, a sign for a blind person, a heavy door for a child. Barrier-free design removes barriers for people with disabilities. Universal design goes further: it makes places easy for everyone from the start.
- Ramp: slope not steeper than about 1:12 (about 8.3 %), with a handrail and a flat landing after each run.
- Doors: clear width about 0.8 to 0.9 m or more; no high doorstep.
- Lifts with large buttons and sound or Braille.
- Tactile paving (bumpy tiles) to guide blind walkers, clear signs and good light.
Guidelines differ a little between countries, so always check the local code. Run of a ramp = 12 × rise.
Try it: measure a ramp at home or school
Try it. Find a ramp. Measure how high it climbs (rise) and how long it is along the ground (run). Divide rise by run and multiply by 100. Is it 8.3 % or gentler? Then use the 3D slider and match your numbers.
Key formulas and definitions
- Coverage ratio = footprint ÷ plot area × 100 %
- FAR = total floor area ÷ plot area
- Ramp slope = rise ÷ run (1:12 ≈ 8.3 %)
- Ramp run ≥ 12 × rise
- Units: area in m², length in m
Worked examples
1. A plot of 200 m² has a house footprint of 90 m² and 3 floors. Find the coverage ratio and FAR.
Coverage = 90 / 200 × 100 = 45 %. Total floor area = 3 × 90 = 270 m². FAR = 270 / 200 = 1.35.
2. A doorstep is 0.15 m high. How long a 1:12 ramp does it need?
Run = 12 × 0.15 = 1.8 m.
3. A school plot allows FAR 1.5 on 2000 m². How much total floor area can be built?
Total floor area = FAR × plot = 1.5 × 2000 = 3000 m².
Common mistakes
- Thinking coverage ratio and FAR are the same: coverage uses one floor's footprint, FAR uses all floors.
- Making a ramp as short as the stairs: it needs about 12 times its height in length.
- Adding access for disabled people at the back door only. Good design gives one main entrance for everyone.
- Planning rooms first and asking about users later. Start with the programme.