Choosing Materials for Arches and Pergolas
From: DK Books - Arches
In general, arches and pergolas should look at home in their surroundings. Just as the size and scale of your construction should be in proportion to that of the house and garden, so their given style should be in keeping, too. The style of a structure owes much to the material from which it is made, although very different effects can be achieved using the same materials.
- Country garden: Oak (or other hardwood) pergola or brick piers with oak beams
- Coastal garden: Reclaimed oak beams or driftwood for a traditional garden. Planed stained wood for a contemporary look
- Roof garden: Strained galvanized wires for overhead climbers or a light plastic pergola
- Riverside garden: Pergola made from machine-rounded wooden poles
- Mountain garden: Pillars built from native stone, with rough-hewn wooden beams
- Formal classical garden: Smooth stone columns with planed, shaped wooden beams
- Town garden: Brick pillars, smooth beams
Influences on Style
While rigid rules about the style of arches and pergolas are inappropriate, one main guideline can be followed: traditional constructions tend to be ideal in gardens of period homes, while more up-to-date structures are suited to modern dwellings.
That said, there is — as with sculpture — a wonderful sense of surprise in discovering a striking, contemporary work of art on the grounds of a country home. This planned juxtaposition of styles can apply to arches, pergolas, and arbors, too, although it is really practical to introduce mixes of style only into larger gardens.
The now truly cosmopolitan aspect of garden design allows you to link the style of a pergola to that of the garden. Books, television programs, and international garden shows have ensured a burgeoning of eclectic garden styles. Anything goes. In a Mediterranean-style garden, for example, a pergola might have clean, uncluttered lines of bright-colored wood; a country garden may have a rustic oak pergola or brick pillars with oak beams; and a modern, city roof garden, with the added influence of weight restrictions, may have overhead strained wires or a light plastic pergola.
Style is about individual choice. Have what you wish, but remember that the most successful constructions are always based on sound design principles rather than short-lived trends.
Wood — the most common medium for arches and pergolas — is available in many forms. Treated softwood is used widely for both posts and beams and is usually supplied as rough-sawn lumber. Planed lumber is smoother, ready to be painted with a choice of colored wood stains.
Hardwoods, particularly oak, are more durable and weather attractively to look especially good with older houses. Such woods tend to be more expensive. If they are your choice, make sure the wood has been sourced from sustainable, managed forests.
Wood, for overhead beams or rafters, is often combined with other materials that form the supporting piers. Bricks are a popular choice; they can have the advantage of matching the house walls. Small, cut blocks of natural stone, known as dressed stone, may also be used; although (as with bricks) construction can be slow and expensive, the result is usually worthwhile. Reconstituted stone is similar, but cheaper.
Wrought iron has traditionally been used to form rose arches, arbors, and pergola tunnels, and it is still perfect in the right setting. Plastic-coated tubular steel is the modern equivalent, which can be just as effective, if more flimsy. These light arches have the added benefit of remaining cool in hot climates, which protects the planting.
Is a Conventional Arch or Pergola for You?
- Such arches have a nostalgic old-world charm, most appropriate in cottage gardens.
- One significant drawback, however, is that they are seldom very sturdy and long-lasting.
- Leaving the bark on round poles achieves a particularly rustic look, but be aware that this will shorten their life.
- Prolong the life of a rustic arch by stripping the bark off the base of the posts and dipping them in preservative before setting them into the ground.
- Rustic arches will not support the weight of heavy climbers such as rambling roses.
Reclaimed wood is a useful alternative to freshly sawn wood. Salvage yards stock all sorts of materials, including old beams, already attractively weathered. Machine-rounded poles associate well with decking and waterside gardens, while painted steel poles make a bold statement, particularly when not softened by plants.
Box-section steel posts and steel girders are most effective used as part of pared-down minimalist designs, and even concrete lintels can be set into walls, forming sturdy overhead beams to support heavy climbers.