Façade systems for commercial buildings

Stick, unitised, structural glazing or steel: how the four ways to build a façade compare, and what testing, fire and energy rules ask of each.

Façades
4 min read
October 2026

Installers guiding a storey-high glazed panel into place high above a city at sunset — Concept visualisation · a unitised panel set from the slab

A façade is the first thing a city sees and the last thing a building forgets¹. On a commercial building it also carries the weather, the fire strategy and much of the energy performance. This is how the main systems compare, and what the rules ask of them.

What a façade has to do

Keep out air and water, resist the wind, hold the glass safely, limit heat loss and solar gain, and meet the fire rules for the building’s height and use. Curtain walling kits are covered by the harmonised European standard EN 13830, which addresses weather resistance, safety in use, and energy economy and heat retention^{2, 1}.

We design, engineer, test and install a façade as one system¹, in aluminium for lightness and precision or in steel for the slimmest sightlines and the longest spans¹.

Four ways to build one

The four façade systems we specify, engineer and install, as compared on our Façade page.
System	Best for	Installation	Fire rating	Typical height
Stick curtain wall	Low and mid-rise, complex geometry	Mullions and transoms assembled on site	EI 15 to EI 60 variants	Up to about 50 m
Unitised curtain wall	Towers and repetitive elevations	Factory-glazed panels set from the slab	By design, per project	Any height
Structural glazing	Flush, all-glass looks	Bonded or toggle-fixed glass, on site or in panels	Limited; for low-risk zones	Any height, in panels
Steel façade	Large spans, fire lines, lobbies	Welded or bolted steel frames on site	Up to EI 90	Lobbies and halls, any span

Stick systems are assembled on site and suit low-rise buildings, complex geometry and smaller contracts. Unitised panels are glazed in the factory and set from the slab, which wins on towers, on speed and on tight sites. When the choice is open, we price both¹.

Tested before site

Before a single panel is made, a full-size mock-up is tested for air, water and wind¹. Curtain walls carry the CE mark to the European product standard, with air permeability, watertightness, wind resistance and impact classes declared¹. Those classes follow EN 12152, EN 12154, EN 13116 and EN 14019¹.

Unitised panels are engineered to about ±1 mm in the factory, and stack joints between them take the building’s sway and the slab’s creep¹.

Fire

Fire-rated façades hold flame and temperature for 15, 30, 45 or 60 minutes, tested as complete assemblies rather than as parts¹. Steel systems go further, to EI 90¹.

In England, Regulation 7(2) of the Building Regulations restricts the materials in the external walls of relevant buildings over 18 metres to class A2-s1,d0 or A1^{1, 3}, and the Building Safety Act adds a gateway review of the façade before work starts¹. Every project is engineered to its local code¹.

Energy and daylight

Heat loss through a curtain wall is given as Ucw. Triple-glazed curtain walls are certified from about 0.6 W/m²K, against about 1.4 to 1.6 W/m²K for thermally broken double-glazed systems¹. Photovoltaic glass can replace spandrel panels or sit in the vision zone, in the same frame¹.

Low-iron glass transmits about 91% of visible light at 4 mm, against about 89% for standard clear glass¹. In the EU, all new buildings must be zero-emission buildings from 1 January 2030, and those owned by public bodies from 1 January 2028^{4, 1}.

Shading

External louvres rotate in front of the glass. Closed, a west elevation becomes a wall; open, the blades all but vanish into the view¹. Fixed façade shutters come in aluminium sections 100 to 300 mm wide, adjustable from 0° to 45°; motorised blades turn further¹.

A double-skin façade puts the blinds inside a second layer of glass, for solar control without losing the view¹.

From brief to handover

Brief. Building, height, market and priorities.
Design. Elevations, modules, finishes and glass, developed with your architect.
Engineering. Thermal, structural, acoustic and fire calculations for every elevation and the local code.
Mock-up and test. A full-size sample tested for air, water and wind.
Fabrication. Profiles extruded, finished and assembled in European works.
Installation. Our own crews, floor by floor, with panels arriving in sequence.
Handover. As-built drawings, warranties, the maintenance plan and the app, in one folder.