Ask the Architect

A column about columns

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Q. We are being told that our new front porch can be held up by fiberglass columns. This is confusing, because we wonder if they would be strong enough to hold up the roof. Is this a common thing to do? The contractor showed us pictures of different kinds of columns, including round and square with different styles, like Roman or plain, etc. What do you think of this idea? We expected wood columns that we could stain or paint.

A. So now I get to write a column about columns. Fiberglass can be molded to many shapes, including boat hulls, car bodies, I-beams and … columns. The material is synthetic, made of resins fused with glass fibers drawn from heated silica, which is basically fine sand, one of the most abundant materials on earth. One window company, Marvin Windows, uses fiberglass for their window frames because it is many times stronger than vinyl.

You could use wood for columns. It’s also one of the most abundant materials found on the planet, but the difference is that fiberglass, once heated, formed and cured, is completely stable and resistant to expansion, contraction, elongation, shrinkage, warping, twisting and rot. Fiberglass I-beams are the structural material of choice for buildings that house corrosive materials such as acids. A battery production facility would utilize fiberglass components, for example.

The one thing about fiberglass columns that I’m concerned about, from a structural design point of view, is the connections needed to other materials. Screws, nails, brackets and bolts may weaken the column unless reinforcement is designed and manufactured into it. Steel columns with steel connections are very strong and reliable, whereas metal to fiberglass, two dissimilar materials, may not be strong enough to resist horizontal forces. To be safe and redundant in the structural reinforcement, I often recommend that the fiberglass, which actually is capable of supporting many thousands of pounds of load, has a steel or wood column inside it, bolted into the foundation support system, to safeguard against the potential of being forced sideways by high winds, falling trees or vehicles.

As for strength and good looks, fiberglass has both in one package, being molded round, with thin lines called flutes, or left smooth, capped with decorative floral ionic styling. Square columns come in many tapered styles or straight sides with raised, colonial-style patterns that are very expensive-looking and impressive for a reasonable cost. Best of all, the fiberglass columns, if painted every 10 years or so, always look good. You won’t regret the decision to have fiberglass columns because, for a lower cost than wood, they need little upkeep, are structurally strong and add so much character to porches, decks and large overhangs. In past generations, columns were used as a face-applied detail, like many fancy moldings and trims. Even though you rarely see columns used this way, the more traditional use, along with face panels and moldings, is making a comeback.

© 2018 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.