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All facades and exterior design articles
Topic guide
Facades and Exterior Design
The facade is the part of a building that has to do the most jobs at once — keep water out, manage heat and vapour, carry its own weight and wind load, survive decades of weather, and look deliberate while doing it. This guide covers how facade systems differ, what actually drives material selection, and how to combine materials without the result reading as arbitrary.
A facade is a system, not a surface
The most common mistake in facade decisions is choosing a material and assuming the system will follow. It works the other way around. The system — how water is managed, how the cladding is supported, how the assembly dries — determines which materials are viable, how they must be detailed, and how long they will last.
Two facades using the same panel can behave completely differently depending on whether there is a drained and ventilated cavity behind it.
The distinction that matters most
Direct-applied (barrier) cladding relies on the outer surface and its joints to keep water out. Fewer layers, thinner build-up, lower cost. The failure mode is that any water that does get past the surface has nowhere to go and no way to dry.
Ventilated (rainscreen) cladding assumes water will get past the outer skin. A cavity behind the cladding drains it and allows air movement so the assembly dries. Thicker, more expensive, more components — and substantially more forgiving.
Climate decides how much that forgiveness is worth. In a dry climate with modest rainfall, a well-detailed barrier wall can perform for decades. In a wet or humid climate, or on a highly exposed elevation, the drying capacity of a ventilated cavity is doing real work.
What actually drives material selection
In rough order of how often it decides the outcome:
- Exposure and climate — driving rain, UV, freeze-thaw cycling, salt.
- Substrate and structure — what the wall can carry, especially in renovation.
- Fire requirements — which for facades is frequently a hard constraint rather than a preference, and varies sharply by jurisdiction and building height.
- Maintenance appetite — who will recoat, reseal or replace, and how often.
- Weight — decides fixing method, and sometimes decides the structure.
- Appearance — colour, texture, module, how it weathers.
Appearance is last on this list and first in most conversations. That inversion is the source of a lot of expensive redesign.
Combining materials
Facades that read as considered usually follow one of a few rules: one dominant material with an accent of a second; materials separated by a clear horizontal or vertical line rather than blended; or a change of material at a change of building form. The failure mode is the “material patchwork” — three or four cladding types applied in similar quantities with no logic to where each one stops.
Every junction between two materials is also a detailing problem — differential movement, different fixing depths, a water path. Fewer transitions is usually better performance as well as better appearance.