How to Make a Pergola Stand Up to New Orleans Weather

A pergola in the New Orleans area has to deal with strong sun, humidity, heavy rain and storm season. The steps that help one last fall into a few areas: wood or metal suited to wet conditions, posts on sound footings, hardware that resists corrosion, a finish you keep up with, and covers you can manage when the wind picks up. This guide walks through each one, whether you are planning a new pergola or protecting the one you already have.

Start With Materials That Suit a Wet, Sunny Climate

Pergola products are available in materials such as wood, aluminum and vinyl. Before you choose, compare how each product is rated for moisture and sun exposure.

Wood. If you choose a naturally durable species such as cedar or redwood, keep in mind that the USDA Forest Products Laboratory’s Wood Handbook notes that only heartwood is decay resistant, so the sapwood from those trees does not carry the same resistance. Pressure-treated lumber is another option for posts and framing. For wood in contact with the ground or embedded in concrete, the International Residential Code calls for pressure-preservative-treated wood suitable for ground contact when that wood supports permanent structures intended for human occupancy. A freestanding pergola may be handled differently under your local code, so confirm with your permit office. We suggest ground-contact-rated posts either way.

Aluminum. If avoiding wood decay is a priority, we suggest considering a powder-coated aluminum frame. Ask the manufacturer how the frame and coating are rated for sun and moisture. See our aluminum powder coating page for options. If you are still choosing between pergola styles, our comparison of bioclimatic and traditional pergolas in New Orleans covers the tradeoffs, and our bioclimatic pergola systems page shows the louvered options we offer.

Anchor Posts on Sound Footings

We recommend having a qualified professional design the posts, footings and anchoring for your pergola, including how it will resist wind. The right approach depends on the pergola’s size, any cover it carries, the site and the code your permit office enforces. A few practical habits apply to most projects:

• Keep wood posts out of standing water. We suggest metal post bases that hold the bottom of a post slightly above the concrete so it can dry after rain.
• If posts are buried or set directly in concrete, use lumber rated for ground contact, as described above.
• Use connectors and brackets sized for the posts and beams they join, and follow the connector manufacturer’s installation instructions.
• Before adding a solid roof or a large fabric canopy, have a qualified professional check the structure and anchoring for the added wind exposure.

Choose Hardware That Resists Corrosion

Moisture and treated lumber can both be hard on metal hardware. A report from the USDA Forest Products Laboratory notes that although wood preservatives increase the service life of wood, in some cases they increase the corrosiveness of the wood to metal fasteners. The same report says that after CCA-treated wood was voluntarily withdrawn from US residential construction in 2004, alkaline copper quaternary (ACQ) and copper azole became two of the most popular alternatives. It cites tests in which both were more corrosive than CCA under the tested conditions, and research finding that relative corrosiveness depended on the metal tested.

The 2018 model International Residential Code generally requires fasteners, including nuts and washers, used with preservative-treated wood to be hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze or copper, subject to the exceptions listed in Section R317.3.1. For connectors, it refers to the connector manufacturer’s coating recommendations and specifies a minimum galvanized coating where the manufacturer gives none. In practice, check the packaging on post bases, hangers and brackets for a rating that matches your lumber, and skip plain steel screws and nails. Confirm which code edition your local permit office enforces.

Protect Wood With the Right Finish

Sunlight starts working on bare wood right away. The Wood Handbook explains that ultraviolet radiation in sunlight initiates photodegradation of wood, and it describes research in which wood facing south for as little as one week before painting had a significantly shorter paint life. For low-density species such as cedar, the handbook advises finishing the wood as soon as possible after installation.

There are two broad types of finish to choose from:

• Penetrating finishes, such as water-repellent preservatives and semitransparent stains, flow into the wood and do not form a film, so they are not generally subject to film cracking or flaking. The handbook notes they may not last very long, and refinishing is simple: clean the surface and apply another coat.
• Film-forming finishes, such as paint and solid-color stain, can last much longer on sound, well-prepared wood. Surface preparation for recoating can be extensive, and the handbook warns that any film-forming finish will be prone to peeling if it is applied to sun-damaged wood.

Pigment matters too. According to the handbook, almost all pigments block ultraviolet radiation, so more pigment generally means more protection. It also notes that mildew growth on a finished surface usually indicates the need for refinishing, which makes a quick look for dark spots part of any routine check.

Pick Covers You Can Manage in Storm Season

An open pergola has open space between its beams. Before adding a cover, we suggest having a qualified professional check whether the structure and anchoring are suitable, and choosing a cover that fits how much attention you can give it when the weather turns.

• Retractable fabric covers give shade on demand and can be pulled back ahead of rough weather. See our retractable pergolas and fabric canopy pages for options.
• Motorized covers with wind sensors. Somfy, which makes motors and controls for awnings, describes wind sensors that automatically retract an awning when the wind picks up. If you add motorized shade, ask whether a wind sensor can be included. Our Somfy motorization page has more detail.
• Louvered aluminum roofs are described by some manufacturers as opening for airflow and closing for rain protection. Verify those capabilities for the specific product, and follow the manufacturer’s guidance on setting the louvers during high winds.

Before a named storm, bring loose items inside. Ready.gov advises clearing drains and gutters and bringing in outside furniture before a hurricane, and we suggest treating pergola cushions, curtains, hanging lights and removable canopy fabric the same way. Our hurricane season roof checklist covers the rest of the house.

A Simple Seasonal Checklist

• Look for loose or rusted fasteners, brackets and post bases.
• Check wood for soft spots, splits and gray, weathered areas that need refinishing.
• Watch for mildew on finished wood, a sign the Wood Handbook links to the need for refinishing.
• Clear leaves and debris from louvers, gutters and the tops of beams.
• Inspect fabric for tears and confirm retractable or motorized covers still open and close smoothly.

Get Help Making Your Pergola Last in the New Orleans Area

TurnKey Patio designs and installs pergolas for homeowners in New Orleans and our surrounding service areas, including Kenner, where we have also written about pergola shade solutions. For layout and shade ideas, see ways to use a pergola for shade and style. We benefit if you hire us, and the steps above are useful no matter who does the work. To talk about a new pergola or protecting an existing one, call (504) 285-2824, Monday through Friday from 8:00 AM to 3:00 PM, or request a free estimate.

Frequently Asked Questions

What is the best wood for a pergola in a humid climate like New Orleans?

There is no single best choice for every yard. Naturally durable species such as cedar and redwood resist decay only in their heartwood, according to the USDA Forest Products Laboratory’s Wood Handbook, so ask what you are getting. Pressure-treated lumber is another option, and we suggest ground-contact-rated lumber for posts set in soil or concrete. If avoiding wood decay is a priority, we suggest considering a powder-coated aluminum frame.

What kind of screws and brackets should I use on a treated wood pergola?

The 2018 model International Residential Code generally requires fasteners, including nuts and washers, used with preservative-treated wood to be hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze or copper, subject to the exceptions in Section R317.3.1, and it refers to the connector manufacturer’s coating recommendations for connectors, with a specified minimum where none exist. USDA Forest Products Laboratory research notes that some wood preservatives make wood more corrosive to metal, so match your hardware to the lumber and confirm the code edition your permit office enforces.

How often should I restain or repaint a wood pergola?

It depends on the finish, the wood and how much sun and rain the pergola gets. The Wood Handbook notes that penetrating finishes such as semitransparent stains may not last very long and require minimal surface preparation to recoat. Film-forming finishes such as paint can last much longer on sound, well-prepared wood, and surface preparation for recoating them can be extensive. Mildew growing on the finish usually means it is time to refinish.

How do I protect a pergola before a hurricane?

Bring in cushions, curtains, lights and any removable canopy fabric, retract motorized or retractable covers, and clear debris from louvers and gutters. Ready.gov advises bringing in outside furniture and clearing drains and gutters before a hurricane. How well the structure itself holds up depends on its design, anchoring and materials, so have a professional review the anchoring before adding a solid roof or large canopy.

Do I need a permit to build a pergola in the New Orleans area?

It depends on your address and the project. Permit requirements vary by jurisdiction and project scope, so ask your city or parish permit office whether the size, a solid roof, attachment to the house or electrical work for lights or fans changes what is required before you build or add a roof.