The Decision Matrix — Choosing a Façade System

A façade is the building’s outer skin: it has to keep wind, water and heat out while carrying its own weight and feeding the wind load back to the structure. The system you pick decides how fast the building closes in, how it performs in Accra’s sun and rain, how it looks, and what it costs. This guide puts the four families side by side — curtain wall, structural glazing, ventilated rainscreen and window-wall — so a buyer, architect or project manager can match the system to the building rather than to a salesperson’s preference.

Facade Ghana has engineered and installed performance façades across Ghana since 1982. The aim of this guide is a clean decision, made early, against real criteria.

The Four Systems — What Each One Is

Curtain Wall (Stick or Unitised)

A glazed, framed outer skin hung past the floor-slab edge so it reads as a continuous wall of glass and infill. It is built either stick (assembled piece by piece on the building, glazed from outside off scaffold) or unitised (storey-height panels factory-glazed and craned in). Stick is the lower-priced entry route and flexible on irregular elevations; unitised is faster on site and the standard for high-rise towers. See Stick-Built Curtain Wall and Unitised Curtain Wall.

Structural Glazing

A curtain wall where the glass is bonded to the frame with structural silicone instead of held by visible pressure caps, so the façade reads as an almost frameless glass face. It buys the flush, high-end look prime corporate buildings ask for, engineered to AAMA structural-silicone guidance. It can be built stick or unitised. See Structural Glazing.

Ventilated Rainscreen

A different principle entirely: an outer cladding panel — ACP, ceramic, terracotta, fibre-cement or stone — is hung in front of an insulated, waterproofed inner wall, with a drained, ventilated cavity between. The outer skin sheds most of the water; the cavity drains and dries the rest. It suits solid-wall buildings and re-cladding, not fully glazed elevations.

Window-Wall

Storey-height glazed units fitted between the floor slabs, slab-to-slab, rather than hung past the slab edge. Lower-priced and simpler for mid-rise residential and hotels, installed floor by floor from inside — but it shows a horizontal slab line and is less continuous than a true curtain wall.

The Comparison Table

System	How it is built	Site speed	Best height / use	Relative cost
Stick curtain wall	Glazed piece-by-piece on the building	Slower; needs external access	Low-to-mid-rise, irregular elevations	Lower-priced entry curtain wall
Unitised curtain wall	Storey-height panels factory-glazed, craned in	Fast; little external access	High-rise towers, fast programmes	Higher up-front; fabrication lead time
Structural glazing	Glass bonded to frame; frameless face	Stick or unitised pace	Prime corporate / high-end aesthetic	Higher-priced (premium look)
Ventilated rainscreen	Outer panel hung over a drained cavity	Moderate; off scaffold/access	Solid-wall buildings, re-cladding	Varies by panel substrate
Window-wall	Storey-height units between slabs, from inside	Fast per floor	Mid-rise residential / hotel	Lower-priced than curtain wall

(Relative cost and speed are directional, not a quote — every façade is priced on survey. See the Curtain Wall Cost Guide.)

How to Choose — Four Questions About the Building

The right system falls out of the building, not out of a product preference.

Height — Low-to-mid-rise gives you the freedom of stick curtain wall or window-wall; a tall tower pushes you to unitised, where little external access and factory glazing matter most.
Programme — A fast, tight programme rewards unitised panels that arrive complete; a relaxed programme or an irregular elevation can take the slower, lower-priced stick route.
Budget — Capped curtain wall and window-wall are the lower-priced glazed routes; structural glazing buys the frameless look at a premium. None of these is a low-grade option — they are different value points.
Aesthetic and wall type — A flush frameless glass face means structural glazing; a solid-wall or re-clad building means a ventilated rainscreen; a continuous glazed skin past the slab edge means a curtain wall, not a window-wall.

The Standards That Decide Engineered vs Assembled

Whichever system you choose, the same performance questions decide whether it is engineered or merely assembled. Facade Ghana specifies and tests against the real standards and never claims a class a system has not been tested to.

ASTM E283 — air leakage through the façade at a set pressure
ASTM E331 — water penetration under static pressure
ASTM E330 — structural performance under positive and negative wind load
AAMA 501 family — field water-penetration and inter-storey-drift testing of the installed wall
EN 1090 — execution of aluminium and steel structures, governing how the system is fabricated

See Façade Performance Testing.

Frequently Asked Questions

Which façade system is best for my building? There is no single best system — the right one depends on height, programme, budget, exposure and the look you want. Low-to-mid-rise on a tight budget often suits a stick curtain wall or window-wall; a tall tower on a fast programme suits unitised; a frameless look points to structural glazing; a solid-wall or re-clad building points to a ventilated rainscreen. We confirm the choice on survey against the building’s real height, access and performance requirement.

Is a curtain wall always better than a window-wall? No. A curtain wall hangs past the slab edge as a continuous skin and performs as one engineered wall; a window-wall fits between slabs and shows a slab line, but it is lower-priced and simpler for mid-rise residential and hotels installed floor by floor from inside. The right choice depends on the building type and budget, not on which sounds more premium.

Can I mix systems on one building? Yes, and it is common — a structural-glazed entrance on a curtain-walled tower, or a rainscreen base under a glazed upper. The interfaces between systems are where performance is won or lost, so they are detailed and tested as carefully as the systems themselves.

Talk to the Façade Team

The cleanest decision is made early, before fabrication, against the real building. Facade Ghana provides a free survey: we confirm height, access, exposure and the performance requirement, then recommend the system that fits — and price it honestly. Call +233 27 000 0844 to book your survey.