Structural vs. decorative columns
Before getting into shapes and finishes, the most important question is structural: will the column actually carry load, or is it wrapping an existing support?
Structural (non-split) columns are designed to bear weight directly. Depending on size and configuration, structural fiberglass columns can support 20,000 lbs or more. These are specified when the column itself is part of the load path, such as a freestanding portico or porte cochere where there’s no underlying post.
Split (decorative) columns, also known as column wraps, are designed to be installed around an existing structural support — typically a steel or pressure-treated post that’s already part of the building’s structure. Split columns are manufactured in two halves, fitted around the post on site, and joined with adhesive and finish work so the seam disappears. This is by far the most common configuration on multifamily and commercial projects, since it lets the architectural detailing be specified independently of the structural engineering
Column shapes for institutional and commercial entries
Square columns offer a cleaner, more contemporary line and are often the default for modern projects where the architectural vocabulary leans simpler. Square columns are typically specified with a box cap and base, and can be detailed with applied moldings for a more traditional look if needed.
Tapered (entasis) columns narrow from base to capital, a detail borrowed from classical architecture that reads as more refined and is frequently specified on traditional or colonial-revival institutional buildings. On round columns, the taper (entasis) typically begins about a third of the way up the shaft; on square columns, an entasis column is straight for the bottom third and tapered above, distinguishing it from a standard tapered square column that tapers along its full height.
Tapered (craftsman) columns are manufactured with a continuous/consistent taper from the bottom of the column to the top. Craftsman columns are almost always square and are often used on farmhouse-style projects and residential applications.
Fluted columns feature shallow vertical grooves running up the shaft, stopping a few inches above the base and below the capital. Fluting is a detail that reads well at a distance making it a good fit for taller institutional entries. It’s available on both round and square shafts.
Chamfered columns are square columns with a beveled edge along the middle of the shaft, transitioning back to a standard 90-degree corner at the top and bottom. This is a subtler decorative detail that works well where a fully classical look isn’t appropriate, but a plain square column feels too austere, it’s a common middle ground on contemporary projects.
Material selection for large-scale projects
Material selection on commercial and institutional projects usually comes down to structural requirements, fire rating, finish, and budget…and the right answer often depends on which of those constraints is driving the decision.
Fiberglass is the most common material for both structural and round columns, available in split or non-split configurations, and finished as primed, gel-coated, or with a custom textured finish that can replicate stone, cast stone, or concrete to match an existing facade. Because fiberglass is lightweight relative to its strength, it’s also a practical choice for upper-floor or roof-level applications where weight matters, as well as extremely large columns (available in sizes up to 60” diameter)
Glass Fiber Reinforced Concrete (GFRC) is a heavier, non-combustible alternative to fiberglass often specified where fire ratings apply, such as on government, university, or larger multi-residential buildings. GFRC is decorative only (not load-bearing), and its custom textured finishes make it a strong value-engineering option on projects originally detailed in cast stone or precast concrete.
Cellular PVC is most often used for column surrounds, square column wraps, column pedestals, and the trim packages that accompany columns (caps, bases, and moldings) rather than for the structural shaft itself. PVC’s machinability makes it well suited to custom profiles and smaller production runs.
Molded polyurethane is generally used for the decorative elements around a column (caps, bases, and brackets), particularly when a project calls for a standard profile in larger quantities, where the economics of a molded product work in its favor over custom-fabricated PVC.
Matching column style to building architecture
Column style should follow the building’s architectural language, not the other way around. A colonial-revival university building or traditional senior living community typically calls for round, tapered columns with classical capitals like Tuscan or Roman Ionic with proportions and details that read as historically grounded. A more contemporary multifamily or mixed-use project tends toward square or chamfered columns with simpler caps and bases, where the column reads more as a structural expression than an ornamental one.
Capital selection matters here too. A Roman Corinthian capital, with its layered acanthus leaf detailing, signals a level of formality appropriate for a clubhouse or institutional entrance, while a plain Tuscan capital is a more restrained option that still reads as classical without competing with the rest of the facade.
From design intent to submittal
Once shape, structure, and material are settled, the next step is moving from design intent to a buildable spec. A few things worth knowing at this stage:
Shop drawings and engineering. For structural columns, engineered shop drawings are often included, showing connection details, load paths, and anchoring — typically prepared in coordination with the column supplier once dimensions and loads are confirmed.
Submittals. Submittal packages for columns generally include material data sheets, finish samples, and shop drawings for the specific profiles and sizes specified. Builders should plan submittal review into the schedule early, particularly on projects with custom profiles that require mold or tooling lead time.
Take-offs. On larger projects with multiple column types, sizes, or locations, a take-off from the construction documents helps confirm quantities and catch discrepancies before the order is placed, which is worth requesting from your supplier during the bidding phase.
Lead times. Standard profiles in PVC or fiberglass generally have shorter lead times than custom polyurethane profiles or non-standard/oversize columns, which require project-specific tooling and mold creation. If a project calls for a custom profile, building that lead time into the schedule early avoids delays later.
Frequently asked questions about columns
What’s the load capacity of a structural fiberglass column?
Depending on size and configuration, full-round structural fiberglass columns can support 20,000 lbs or more, which is sufficient for most porch, portico, and porte cochere applications. Exact capacity should be confirmed with engineering based on the specific column size and connection details.
Can column covers be specified to wrap an existing structural post?
Yes, this is the split-column configuration, designed in two halves that are installed around an existing steel or pressure-treated post and joined on-site. It’s the most common approach when the structural engineering is already determined independently of the architectural column detailing.
Do you provide engineered shop drawings and submittals?
Yes. Once column sizes, locations, and loads are confirmed, a shop drawing package can be prepared showing connection details and anchoring, along with the material data sheets and finish samples needed for submittal review.
How do GFRC and fiberglass compare for fire-rated applications?
GFRC is non-combustible, making it a common choice where fire ratings apply — government buildings, universities, and larger multi-residential projects. Fiberglass is combustible and is typically specified where fire rating isn’t a constraint, or where its lighter weight and structural capacity are the priority.
Ready to start your column spec?
If you’re working through column specifications for an upcoming project — whether it’s a single portico or a full exterior trim package across a multi-building development — we’re happy to help with material recommendations, take-offs, and shop drawings. Contact Decoro to discuss your project.