Iron railings outside a home usually are installed along a walkway or on the stairs leading to an entry door. Though metal is rugged and can last years even when exposed to the elements, annual attention to address any problems will slow deterioration and oxidation while maintaining an attractive appearance. If railings require emergency help, spend considerable time scraping, patching and painting the first time. After that, regular maintenance should not require much time.
Clear away vegetation. With a hand-held branch cutter, remove any branches from bushes or shrubs that brush up against the iron railings. The moisture on leaves and branches that become intertwined with or are pushed up against the railings will spread the raindrops and dew onto the metal. This moisture, over time, breaks down the protective paint surface and eats into the iron. Clearing vegetation immediately around the railings will encourage air circulation that will dry the dampness after a rainfall.
Scrape the iron surface. Place a drop cloth, small tarp or newspaper under the railings to catch any debris removed from the railings and any drippings that occur during the surface prep and painting steps. Use a scraper to remove any loose paint, dirt and crusts of rust. With a wire brush, hand-held abrasives or power tools or accessories for power drills, remove remaining corrosion down to the bare metal. Carefully inspect all areas of the railing, including the handrails, spindles and any decorative sections.
Prep the surface. Some areas, especially under railings and where spindles meet the railings, might have slight deterioration that require repair. Apply metal or mesh patches cut to size to cover the damaged areas. Adhesives or bonding agents made for metal, or solder, will be needed to keep these repairs in place. Sand any patches so they blend with the rest of the metal. Sand away any burrs or other uneven areas.
Apply an undercoat. Use a metal primer that is applied with a narrow paintbrush to help get paint into all tight areas and around any decorative sections. Sometimes, two coats are required, especially if you have sanded the surface to the bare metal or have added patches. Allow the first coat to dry thoroughly before adding a second coat.
Apply the topcoat. Select the desired color. Most railings are either black or white, but paint for outdoor metal comes in a variety of colors to complement the color of a home. Apply the paint with a clean narrow paintbrush. Two coats will provide adequate coverage and added protection. Allow the first coat to thoroughly dry before adding the second.
Clean up the area. After all work is completed, carefully remove the protective covering that was placed under the railings. Either discard or shake it out in a trash can if you plan to use it again.
Always wear eye protection when using power tools.