Royal Corinthian manufactures round non-tapered columns from 3 composite materials: Composite Fiberglass, Polymer Stone, and FRP Lightweight Fiberglass. All three materials are available in all of the sizes below. We are able to create additional diameters by taking the bottom portions of our tapered columns so if you are looking for 6”, 22”, 28”, 30”, or 36” diameter non-tapered porch columns, please call or email for additional information. We differ from the rest of the industry in that our non-tapered columns have astragals that are part of the shaft which saves a lot in terms of installation costs if you have to attach loose astragals on site. If you do not desire to have an attached neck ring, we are able to remove them from the shaft at no cost. The majority of our non-tapered columns come with a cap support ring that holds up a Tuscan capital, which is very useful especially when using some of our heavier materials. The cap support ring is removed in instances where decorative capitals are used. The structural supports chart below corresponds to our RoyalCast fiberglass columns: Synthetic stone columns tend to be slighter thicker and RoyaLite columns tend to be thinner. Exact specifications for the aforementioned are available upon request or via shop drawings. The load bearing specifications chart pertains only to RoyalCast and RoyalStone columns: RoyaLite columns are typically used as column covers but in instances where we assemble them into whole columns, the load bearing capacities will be significantly lower than on the chart below.