Flagpole materials in Canada: aluminum, fibreglass, steel or wood?

A flagpole in Canada is exposed to wind, ice, snow, road salt and, on the coasts, salt spray. Canadian Heritage defines a flagpole simply as a cylindrical piece of wood or metal to which a flag is attached or from which it is hoisted. In practice, most outdoor poles today are aluminum, with fibreglass and steel as alternatives and wood as a traditional material.

Aluminum

Aluminum is light, does not rust and can be shaped into tapered poles. According to Flag Outlet, a flagpole maker in Coquitlam, B.C., the 6063 aluminum alloy is the industry standard; after welding, its poles are heat-treated to a T-6 temper, and cone-tapered poles narrow by one inch for every 5.5 feet. The company makes its poles in accordance with the specifications of NAAMM, the National Association of Architectural Metal Manufacturers.

Aluminum poles come in several finishes:

• Anodized: according to Flag Outlet, the best surface for a flagpole: a thin, hard layer of oxide grown out of the metal, about six thousandths of an inch thick, which cannot peel like a plated finish, resists corrosion and keeps aluminum oxide off the flag.
• Satin brushed: the bare, brushed metal, which discolours over time.
• Powder-coated: a coloured coating, offered for instance on nautical poles.

Fibreglass

Fibreglass poles are light and do not corrode. Flag Outlet sells 15- and 21-foot fibreglass poles, set in a PVC ground sleeve, which it describes as maintenance free and without a clanging rope. Fibreglass is also a non-conductive material, which is why Hydro-Québec mentions fibreglass or wood for ladders used near power lines; near a power line, however, the distance that counts is the one described in the guide to flagpole safety.

Steel

Steel is strong and heavy. Flag Outlet’s sectional poles for backyards and cottages are made of Galvalume steel, coated with an aluminum-zinc alloy against rust. Uncoated steel rusts, especially where salt is present, so steel poles are galvanized, coated or painted.

Wood

Historically, flagpoles and ships’ masts were made of timber; Canadian Heritage’s glossary still describes a mast as a long pole of timber, iron or steel. A wooden pole needs regular painting and can rot at the base, where it meets the ground.

Colour and finish

Most aluminum poles are left in their natural metal colour or anodized clear. For public buildings, the Gouvernement du Québec describes a more formal look: a dark mast – dark bronze, black or navy – topped by a gold ball about 150 mm (6 in) in diameter. A dark finish makes the mast stand out from lamps, poles and other fixtures around it.

Canadian climate

• Cold and ice: ice can build up on the halyard and the flag. Parliament Hill’s flags are not changed in snowstorms or high winds, for safety reasons.
• Salt: road salt and coastal salt spray attack coatings and fittings; stainless or aluminum fittings resist them better than plain steel.
• Wind: according to Flag Outlet, the principal load on a flagpole is wind. Wind speeds are generally higher along the coasts than inland, higher in open country than in city centres, and greater the higher above the ground.

Care of the finish

Flag Outlet notes that a satin brushed finish discolours. It describes cleaning with soap and water, to which a mild household acid such as lemon juice or vinegar can be added, but not ammonia, TSP or soda, and says a coat of car wax or a silicone spray helps protect the aluminum. More in the guides to flagpole maintenance and flagpole lifespan.