Facade Window Surrounds and Window Framing
Facade window surrounds are profiled frames around window openings on the outside of a building. They cover the junction between wall and reveal, frame the window and, together with a pediment and a sill element, turn the opening into a finished architectural detail. On multi-storey buildings it is usually the window surrounds that decide whether a facade looks classical or merely rendered.
The main selection criterion is compatibility with the facade system and the windows: the surround must fit the window junction detail, must not obstruct casements and sills and must not create a water trap. Shape and material are chosen after that.
This article is for architects, general contractors and home owners deciding what to make exterior window surrounds from and how to install them. The overall picture is in the section Architectural Facade Details.
What Window Surrounds Do
Window framing on a facade solves several tasks at once.
• Compositional. The surround highlights the opening, sets the rhythm of windows on the wall and helps build a hierarchy of storeys: on the principal floor the surrounds are richer, on the upper floors simpler.
• Scale. A wide frame visually enlarges the window, a narrow one makes it more austere. This allows the proportions of openings dictated by floor plans to be adjusted.
• Protective. A projecting surround, and especially the pediment above it, sheds water away from the head reveal and the window unit.
• Technical. The framing conceals the window installation joint, the junction of insulation and reveal and any irregularities at the edge of the opening.
Window surround decor is designed together with the window detail, not applied on top of a finished facade. If windows and sills are installed first and surrounds are chosen afterwards, the profile has to be trimmed or moved away from the frame, and the surround loses its proportions.
Types of Window Surrounds
Exterior window surrounds are classified by shape and by their components.
| Type | Description | Where appropriate |
|---|---|---|
| Simple frame | a single-section profile around the perimeter of the opening | modern classicism, upper floors |
| Eared frame (crossettes) | projections at the upper corners | neoclassical, Baroque |
| Frame with keystone | an accent element in the centre of the head | principal floors, arched windows |
| Full surround | frame + pediment + sill element with brackets | main facades, private houses |
| Archivolt | profiled framing of an arched opening | arched windows and entrances |
What to make facade window surrounds from depends on the system: on a rendered facade, run-in-place render mouldings, GFRC or stone units are used; on a ventilated rainscreen facade, GFRC, stone or special profiles fixed to the substructure. GFRC surrounds are cast in bespoke moulds, so the profile can follow the architect's drawing — from a simple ledge to a multi-stepped ornamented frame.
The viewing distance is taken into account when choosing a type. Windows on the first two floors are seen close up, which justifies fine profiles, panels and crossettes. On upper floors the same details merge, so frames are made bolder and simpler, and the accent shifts to the pediment and cornice. A single facade usually uses two or three types of framing, separated by tier, rather than different frames on adjacent windows.
Window Pediments and Sill Elements
A full window surround consists of more than just the frame.
• Pediment (hood) — a small projecting cornice above the window: straight, triangular or segmental. It sheds water and visually caps the opening.
• Frieze — a plain or ornamented field between the frame and the pediment.
• Sill element — a ledge or profiled sill below the window, often with brackets; sometimes a balustrade or panel is placed beneath it.
• Brackets (corbels) — support the pediment or sill ledge visually and sometimes structurally.
Pediments and sill elements are the parts of the surround most exposed to water. Their top surfaces are sloped away from the wall, and a drip is formed along the lower edge so that water does not run onto the wall. The sill element does not replace the window sill flashing: the metal flashing remains part of the window detail, and the decorative ledge sits below it or over it with managed drainage. Pediments are covered in detail in a separate article in this section.
Materials
| Material | Pros | Limitations |
|---|---|---|
| GFRC | low weight, complex profiles; according to the manufacturer, non-combustible (NG class) and frost-resistant | made from moulds, requires a fixing design |
| Natural stone | durability, genuine texture | weight, cost of profiling |
| Run render mouldings | made on site, no joints | labour-intensive, dependent on skill and weather |
| Foam with reinforced coating | cheap, light | combustibility, height restrictions, vulnerability to impact |
| Timber | traditional look for timber houses | requires regular maintenance |
For multi-storey buildings with rainscreen facades, GFRC window surrounds are a rational choice: the units are non-combustible, do not load the substructure as much as stone, and allow one profile to be repeated on hundreds of windows with identical geometry. Stone is chosen for plinths, ground floors and private houses where natural texture matters. Properties of specific products are given in the data sheet.
Installation Around Windows
Installation of window surrounds is coordinated with the windows at the working drawings stage.
1. Sequence. Usually the windows are installed first and the junction detail completed (vapour barrier, installation foam, breathable tape), then insulation and cladding, and only then the surrounds. If a surround runs under the sill flashing or onto the frame, the order is changed per the design.
2. Gaps. A joint is left between the frame and the window unit and filled with sealant: the window and the facade move differently.
3. Casements. Check that the profile does not obstruct opening of casements or cover the frame's drainage slots.
4. Fixing. GFRC units are anchored to the load-bearing wall through embedded fixings or to the rainscreen substructure without blocking the ventilation cavity.
5. Head and sill. Above the window — a pediment with a fall and a drip; below the window — a flashing and a sill element with managed drainage.
At TECHNOFORMA Group, details are designed by the in-house design department and installation is carried out by the in-house installation division, which allows windows, insulation and decor to be coordinated in one design.
Examples from TECHNOFORMA Projects
TECHNOFORMA Group delivers facades with GFRC decor from design to installation. Examples: the Dominanta residential complex in Makhachkala (18 storeys, 4 buildings, 14,000 m² of GFRC and 13,000 m² of porcelain stoneware) and the Na Sovetskoy residential complex in Cherkessk (15 storeys, 6,000 m² of GFRC). The window framing solutions can be seen in the project photos.
See all TECHNOFORMA projects and continue with Window Pediments: Types and Purpose.
FAQ
What should exterior window surrounds be made of?
For multi-storey buildings, GFRC or stone; on rendered facades, also run render mouldings. Foam decor is restricted by fire safety requirements.
When are window surrounds installed — before or after the windows?
Usually after the windows, insulation and cladding, but the sequence is determined by the junction detail in the design.
Can GFRC window surrounds be installed on a ventilated facade?
Yes, they are fixed to the substructure or to the load-bearing wall through the insulation, keeping the ventilation cavity clear.
Is a sill flashing needed if there is a decorative sill element?
Yes. The metal flashing is part of the window detail; a decorative ledge does not replace it.
What does a full window surround include?
A frame (architrave), a pediment above the window, sometimes a frieze, a sill element and brackets.
