Why Does My Wood Floor Have Stains? Tannin Pull and How to Fix It

Hardwood floors are so loved because they’re both beautiful and easy to maintain compared to the problems that other types of flooring can present. Still, they are not completely immune. Certain environmental conditions or the improper application of floor treatments can cause issues you may need to address.

One of these problems is tannin pull, a type of staining that can appear due to various causes. If you’ve seen unusual or unexpected colors appear on your hardwood flooring, you’ll want to know how to remove tannin stains from wood.

Tannins Present in Wooden Flooring

Many active chemicals are present in wood; among them, tannin is the most prevalent. Tannin is soluble in water and can react with water-based products or environmental moisture, resulting in discoloration.

Tannin pulling can appear as blotches of red, green, or even purple coloring. These blemishes occur more frequently in woods with high tannin content, such as cherry, mahogany, oak, and walnut.

Oak is a popular material for floorboards because of its natural beauty and the dramatic effect available through specific treatments. Unfortunately, this type of flooring is the most susceptible to tannin pulling.

Understanding Tannin Pull

In the case of painted surfaces, inadequate application of primer or failure to seal the surface before applying paint can allow tannins to rise to the surface of the wood. Tannin-resistant primers should always be applied to oaks or other types of wood high in tannic acid.

The primer should be allowed to dry entirely and checked for surface discoloration. Any affected areas should be lightly sanded, and a second coat of primer applied.

Sometimes, discoloration from tannins can be the result of the uneven application of stains or other pigments. If these pigments fail to penetrate the upper layers of hardwood completely, tannin can “pull” through the stain or pigment to the surface of the wood.

Excess humidity, wet subflooring, or moisture seeping up from beneath wooden flooring can also react with tannic acid, freeing it up to rise to the surface, where it forms large blotches of unwanted color.

The proper application of high-quality surface treatments is essential. Most often, tannin pulling results from a water-based finish that has been allowed to puddle on the surface of wooden flooring for too long. The water causes tannins in the wood to seep (or pull) to the surface, which results in discoloration that can be difficult to repair or remove.

How To Remove Tannin Stains from Wood

When it comes to removing tannin stains, there are several options. Depending on the severity or extent of the tannin pull, the unwanted discoloration can require thorough sanding.

Go over the stained section of flooring with a fine grain of sandpaper until the unwanted color is eradicated. Assess the area for any lingering dampness or excess moisture before reapplying the stain or other pigment.

In some cases, sanding may be required over a larger area to expose the natural color of the wood beyond the borders of the tannin pull. This will help to ensure even pigmentation across the flooring when it is re-stained.

A better option for removing tannin stains is to use a product specifically formulated for such a purpose, such as Rubio Monocoat Tannin Remover. It can be applied evenly to surface areas affected by tannin pulls and is a much easier method to deal with unwanted surface discoloration.

Tannin Pulls Happen

Nothing gives a home a sense of warmth or opulence like hardwood flooring, and the shine and luster of a properly maintained wooden floor can make a room feel cozy and inviting.

Hardwood flooring is versatile, durable, and unmatched by other options for beauty and value. Luckily, problems such as staining caused by tannin pulling are uncommon. If it occurs, it is typically quite easy to repair.