The face is the part of a billboard people actually see, and its frame decides how that face looks after the first strong wind. A frame that is out of square, has uneven tensioning points or collects water will show wrinkles, flutter and early wear however good the print is.
We fabricate billboard frames to suit the structure and the skin, and we install the faces on them. This page covers the frame types, how skins attach and what to consider when choosing.
Typical specifications
- Frame materialgalvanised or painted steel sections, or aluminium extrusion for lighter boxes
- Face formatsfor example 6 m x 3 m, 12 m x 3 m and 18 m x 6 m, plus custom sizes
- Skin typesPVC and flex, mesh and backlit material
- Fixingwelded hems, eyelets, keder rail or perimeter track
- Tensioningbalanced pattern to avoid distortion
- Fittingslighting brackets, trims and cable access
- Accesswalkway, catwalk and tie-off points designed with the frame
Frame construction
Most large billboard frames are welded steel sections, galvanised or painted, bolted to the head frame of the structure. Lighter faces or backlit boxes may use aluminium extrusions with a cover trim. The frame is built in sections so it can be lifted and joined at height, and the joints are detailed to stay flat.
Sizes follow the standard formats in use in South Africa, for example 6 m x 3 m, 12 m x 3 m and 18 m x 6 m, with custom portrait and vertical faces available. See the billboard sizes guide.
Edge details protect the skin. Hems are reinforced where the skin meets the frame, corners are rounded so that tension does not concentrate on a sharp edge, and the trim hides fixings and keeps wind from getting behind the skin and lifting it. Frame joints are sealed on lit boxes, so water and dust do not enter.
How skins attach
PVC and flex skins are usually fixed with welded hems, eyelets or a keder rail and tensioned in a balanced pattern so the load spreads across the frame. Mesh skins are tensioned more lightly and use fixings that suit the open weave, which also reduces wind load on the structure. Backlit skins are stretched across a lit box and held by a perimeter track or trim.
Tensioning has a limit: over-tightening tears hems and distorts the frame. We follow the material and print requirements, which you can read in the artwork requirements.
Print resolution and viewing distance affect material choice. A large face seen from a highway at speed does not need the fine detail of a poster, but it does need strong contrast and clean colour. Seams in a large skin are welded and placed with the artwork in mind, so that they do not cut through a face or a logo. See billboard skin printing.
Static, backlit and tri-vision faces
Static faces are printed skins. Backlit faces need a box with internal light and a translucent skin. Tri-vision faces use rotating triangular slats and need a mechanism, drive and power supply. Each changes the frame and the structure behind it, so the face type should be settled before the structure is designed.
See backlit billboards and tri-vision billboards.
Wind shapes the choice of material and tension. Mesh lets a share of the wind pass through and suits very exposed sites, while PVC acts as a solid sail and demands a stronger frame and fixing. Slack skins flutter, tighten unevenly and fail early, which is why correct tensioning at installation and a check after the first few weeks are both worth doing.
Access and safe flighting
A good frame includes places to stand, tie off and work. Service walkways, catwalks and attachment points are designed with the frame so flighting crews can fit, tension and change skins safely. Flighting follows the applicable health and safety requirements, and rope access is available where a walkway is not practical. See billboard flighting.
Frames can be built for more than one face on a structure, as on double-sided, V-shape and trihedron billboards. Each face needs its own frame, and the structure behind must carry the combined load. Rotating faces use a drive and a control system that need space and power at the head frame, which affects the structure design from the outset.
Repairs and replacement
Frames suffer from corrosion, impact and wind fatigue. A bent member, a cracked weld or rusted corners can be repaired by cutting out the damaged section and welding in a new piece, followed by recoating. If a frame is beyond repair, it can be replaced to match the existing structure and face size.
Torn or worn skins can be replaced on an existing frame, which is simpler than rebuilding the frame. See billboard repairs and maintenance for how we handle ongoing care.
At a glance
Billboard faces and frames from Billboards Africa are built to hold PVC, mesh and backlit skins flat and tight in South African wind and sun. We fabricate steel and aluminium frames in standard formats such as 6 m x 3 m, 12 m x 3 m and 18 m x 6 m, as well as custom portrait faces, and fit them to unipoles, lattice structures, rooftops and walls.
Getting billboard faces and frames right means choosing the skin first: mesh for exposed highways like the N1 and N4, PVC for strong colour on urban sites in Sandton and Rosebank, and backlit material for lit boxes. We design tensioning, fixings, trims and access together so flighting crews can fit and change skins safely. Approvals rest with the municipality, roads authority and landowner, and we assist with supporting documents. Use the quote form to request a quotation for billboard faces and frames anywhere in South Africa. Face type, frame and fixings are confirmed together so the skin and the structure suit each other. We also repair bent frames and replace worn skins, and can fit new frames to structures built by other suppliers once the head frame has been measured and checked.
Common questions
Can you build a frame for an existing structure?
Yes, after we measure the head frame and check the structure can carry the new face. Details are confirmed on your quotation.
Which skin suits a windy site?
Mesh reduces wind load because air passes through it. PVC gives stronger colour. We recommend based on the site and the structure.
Can the frame be changed from static to backlit?
Sometimes. The structure must carry the added weight and power supply, and approvals may be needed. See upgrades.
Who flights the face?
We can print and flight your skin, or flight skins you supply, with sizes and finishing confirmed on your quotation.
Do you repair damaged frames?
Yes. Bent, corroded or distorted frames can be repaired or replaced.
