Building Accessories
Fascias and Parapets for Pre-Engineered Steel Buildings
Definition: A fascia is a vertical or angled cladding band fixed to brackets at the roof edge of a metal building, while a parapet is a wall extension that rises above the roof line. Both give the building a strong architectural edge, hide the roof slope and can carry signage.
Key facts
- Fascias can be flat, sloped, curved or boxed to suit the architectural style.
- Parapets are often formed by extending columns and girts above the eave.
- Wind pressure on both faces of a parapet often governs its framing.
- Parapets usually create an internal gutter that needs overflow protection.
- A back panel or liner closes the inside face of the fascia framing.
Role in the structure
Fascias and parapets are carried by brackets, posts or extended columns fixed to the main frame. Wind acts on both faces of a parapet and on the front of a fascia, creating moments in the brackets and columns that must be included in the frame design. Parapets usually require an internal gutter behind the wall, which affects roof drainage and waterproofing.
Fascia systems on metal buildings
A fascia is a band of panels attached to the building edge, either flush with the wall or projecting from it. Brackets fixed to the columns or eave strut support horizontal girts, and the fascia panels are fixed to these girts. A bottom soffit and top cap complete the box.
Fascias are used to give an industrial building a commercial appearance, to conceal rooftop equipment and to provide a surface for signage. Different panel profiles or colors can be used on the fascia to contrast with the walls.
Parapet walls and their structural framing
A parapet extends the wall above the roof. The main columns or separate parapet posts continue above the eave and support girts and panels on the outer face, often with a liner on the inside face. The top is closed with a coping or cap flashing.
Wind on a parapet acts in both directions and can be high at corners. The parapet posts and their connections must resist this, and the main frame must carry the extra moment. Parapets may also cause snow to accumulate on the roof behind them in cold regions, which the project engineer considers in the roof design.
Drainage behind parapets
When the roof slopes toward a parapet, water collects in an internal or box gutter between the roof and the parapet. This gutter must be sized for the roof area and rainfall intensity, and overflow outlets or scuppers should be provided so that blocked outlets do not cause water to enter the building.
Internal gutters need careful waterproofing at joints and outlets, and regular cleaning. Where possible, sloping the roof away from the parapet and using external gutters reduces risk.
Materials & coatings
- Steel brackets, posts and extended columns, primed or painted.
- Cold-formed girts and channels for fascia and parapet framing.
- Profiled or flat architectural wall panels, and liner panels for back faces.
- Coping, cap flashings, soffit trims and internal gutters.
Design considerations
- Height and projection of the fascia or parapet.
- Wind pressure on both faces and at corners.
- Additional moments and loads on the main frame columns.
- Roof drainage behind parapets, including overflow provision.
- Snow accumulation behind parapets in cold regions.
- Signage loads and access for maintenance.
Fabrication
- Brackets and extended columns are fabricated with the main frame.
- Fascia girts are cut and punched to suit bracket spacing.
- Panels, caps and trims are formed to the fascia profile.
- Internal gutters are formed in lengths with joints prepared for sealing.
Erection
- Install brackets or parapet posts after the main frame is aligned.
- Fit girts and check that the fascia line is straight and level.
- Install back liner, outer panels, soffit and cap in sequence.
- Install and seal internal gutters and outlets before roofing is completed.
Inspection & quality
- Check fascia alignment and panel fixings.
- Inspect coping and cap flashings for continuous sealing.
- Test internal gutter outlets and overflow paths.
- Look for gaps where birds or water could enter the fascia cavity.
What to include in your RFQ
- Fascia or parapet type, height and location on each elevation.
- Panel profile and colors, including back liner if required.
- Roof drainage arrangement and gutter type behind parapets.
- Any signage or equipment to be supported.
- Architectural features such as curves or soffits.
3D model & IFC of this component
Rotate the model, isolate the component and download its IFC4 file for your BIM coordination model.
IFC entity: IfcCovering + IfcMember. Illustrative geometry for coordination and learning. Final member sizes come from the project design.
Frequently Asked Questions
What is the difference between a fascia and a parapet?
A fascia is a band of cladding at the roof edge, carried on brackets. A parapet is a wall that rises above the roof, usually with an internal gutter behind it.
Do parapets increase leak risk?
They can, because internal gutters collect water inside the building line. Good sizing, overflow outlets and maintenance reduce this risk.
Can a fascia hide rooftop equipment?
Yes. A tall fascia or parapet can screen roof-mounted units from street level, provided its height and loads are included in the design.
Engineering content is general guidance. Every World Steel building is designed by qualified engineers to the code and loads of the project.
