What Is a Building Facade? Definition, Layers and How It Works

What a facade has to do

Resolve the applicable performance requirements in the selected build-up. The six rows below are a functional checklist, not six mandatory physical layers; several functions may share a material.

The most common design error is treating the top row and the bottom row as the whole problem.

The two meanings of “facade”

The word carries a technical meaning and an architectural one, and conversations go wrong when the two get mixed.

Technically, a facade is the exterior wall assembly: everything between the interior finish and the outside air, working together to control water, air, heat and vapour while carrying its own weight.

Architecturally, a facade is the composed public face of a building — the elevation that is deliberately designed to be seen and understood from the street. A building has several exterior walls; it usually has one facade in this sense.

This article is mostly about the first meaning, because that is where the decisions with consequences live.

What is the fake front of a building called?

The outside front of any building is its facade, or front facade. A fake front, built to look like more building than there is, is usually called a false front. History Colorado describes a false front as a front wall that extends above the roof and the sides of a building to create a more impressive facade. Seen from the street, the building looks taller and squarer than it is; from the side, the gable roof behind the raised wall gives it away.

The type it describes has four defining features:

• The street facade rises into a parapet, an upper wall, that hides most or all of the roof.
• The roof behind is almost always a front gable.
• The facade often uses better materials than the sides and rear.
• The facade carries more ornament than the other sides.

The reason was economic. In Colorado’s mining, farming and railroad towns of the late nineteenth and early twentieth centuries, owners wanted to look stable and established without investing heavily in the whole building, so they spent on the street front and gave the secondary sides a cheaper, utilitarian treatment.

How a false front differs from a facade. Every building has exterior walls, and most have a facade in the architectural sense. A false front is a particular kind of facade: one designed to make the building read as larger or more substantial than the structure behind it. The front elevation is the drawing of that face, which is a separate idea; see floor plan vs elevation.

How it differs from facadism. Facadism, sometimes called a facadectomy, keeps the facade of an existing building and constructs a new structure behind or within it. Preservation Detroit notes that it often results from a compromise between a developer and the local historic commission or preservation community. A false front was built to exaggerate the original building; facadism keeps an old face on a new one.

A typical layered build-up

Working from outside in, a contemporary drained facade often reads roughly as:

1. Cladding — the visible material.
2. Cavity — a drained and often ventilated air space.
3. Support system — rails, brackets or battens carrying the cladding back to the structure.
4. Insulation — usually continuous, outboard of the structure where possible.
5. Water-resistive and air control — membranes, coatings or other suitable materials; these functions may share a layer.
6. Structural backing — sheathing over framing, concrete, or masonry.
7. Interior finish.

Not every facade has all seven, and the order changes with climate and system. A traditional solid masonry wall combines several of these functions in one thickness of material.

Facade families

Load-bearing walls carry the structure above as well as enclosing the building. Solid masonry is the classic case.

Cavity walls place an outer leaf and an inner leaf either side of a cavity, so water crossing the outer leaf drains rather than reaching the interior.

Rainscreen or ventilated facades assume water will pass the outer skin and manage it in a drained, ventilated cavity behind. See ventilated facade vs direct-applied cladding for how this differs in practice.

Curtain walls are non-load-bearing systems, typically framed in aluminium and infilled with glass or panels, hung off the building’s structural frame.

Direct application describes how a finish is attached — for example render or adhered tile. Check the complete section: bonded systems can also include water barriers and drainage details.

The distinctions matter to water management, alongside material, detailing, exposure and maintenance. Types of facade systems covers the differences in more detail.

Why the drying question dominates

Drainage removes liquid water; drying removes moisture through evaporation and vapour transport. WBDG’s Moisture Movement discussion distinguishes leakage, air-carried moisture and diffusion, and describes face-sealed and drained rain-control strategies.

For a drained assembly, check that flashings and exits connect to the drainage plane. For drying, check layer permeability and the indoor/outdoor conditions. No ventilation cavity does not mean no drying, and a cavity alone does not ensure a wet wall will recover.

WBDG’s Air Barrier Systems guidance addresses continuity through materials, joints and transitions; an air barrier and a vapour retarder perform different functions even when one product serves both.

Takeaway: Trace the water and air paths through the actual wall; this page establishes no service-life difference.

What to look at on a real facade

• Where the drainage plane is, and where water leaving it actually goes.
• Whether the air barrier is continuous, including at floor lines, corners and around openings.
• Where the insulation sits relative to the structure, and whether it is interrupted by fixings and framing.
• How each junction between materials is detailed, and whether it relies on sealant as the only line of defence.
• What has to be done, and how often, to keep it performing.

For how these assemblies differ once you start specifying them, continue with the facades and exterior design guide, or go straight to exterior wall cladding materials compared.