How To Clean Those Strange Yellow Stains On Your Stair Trim

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Notable discoloration can put a damper on any element of the home. In places where crisp white paint provides a fresh feeling, you'll want the color to look uniform and pristine. This is especially true when it comes to cosmetic applications, like trims and moldings. Many homeowners use wood for their trim because of the material's durability and richness. But if yellow stains are appearing on wood trim, they're not just surface dirt and debris that can be wiped away with common cleaning tools. It's a deeper issue that has to do with compounds in the wood called tannins. Stains and damage to the appearance of the wood can happen as the result of an issue known as tannin bleed. 

Home DIY influencer letitiakiu explained that tannin bleed is a "naturally occurring acid coming up from the wood and showing up through your paint." This is common when water-based paint is used to cover wood trim. While the easy fix would be to add new coats of paint over it, that won't stop tannin bleed from happening again in the future. The Instagrammer shared their DIY solution to the problem: Go over the trim with an oil-based primer. Working with an oil-based primer is just as easy as using a water-based paint, but the chemicals will stand up against tannin bleed to make sure it is not visual on trim.

Authentic hardwood includes tannins, which help preserve the wood's integrity and also establish the color and visual of the wood. When tannins in the wood change over time, this causes tannin bleed to occur. It will cause the wood to look different, giving off the appearance of unsightly marks and imperfections. While not pretty, tannin bleed is fairly common and not something to panic about. Luckily, this is a cosmetic issue and will not be trouble in terms of structure or performance. The problem is with the wood itself rather than the paint, but that does not mean you'll need to repair damaged wood trim. 

To prevent tannin bleed from returning, the Instagrammer used Rust-Oleum Oil-Base Stain Blocker Primer, which is specifically formulated to block stains. The primer is odorless, so the change from a water to an oil base won't bring any new smells into your home. First, prep the surface by scuffing the trim, and then use a paintbrush to apply the oil-based primer. Oil-based primers in a spray format are also available on Amazon for an easy and time-saving application. When this is completed, use the original paint color or finish for a fresh top coat so the trim looks consistent. Now, your painted trim will look great and make a big difference in your room!