Is it okay to power wash a Trex deck?

Power washing, also known as pressure washing, is a common way to clean outdoor surfaces like decks. Power washers use high-pressure water to remove dirt, grime, mold, and mildew. Many homeowners use power washing for routine deck maintenance.

However, power washing requires caution when used on certain deck materials like Trex. Trex is a popular composite decking material made from recycled plastic and wood fibers. It provides the look of real wood without all the maintenance. But Trex has special cleaning requirements compared to real wood. So is it okay to power wash a Trex deck?

The short answer is yes, you can power wash a Trex deck, but there are a few important guidelines to follow. In this article, we’ll explain:

• What is Trex decking?
• Can you pressure wash Trex decking?
• Recommend PSI for washing Trex decks
• Best practices and tips for power washing Trex
• Risks and potential damage from power washing Trex
• Alternatives to power washing Trex decks

Follow these recommendations to safely refresh your Trex deck using a power washer.

What is Trex Decking?

Trex is a leading brand of composite decking that dominates much of the synthetic decking market. Rather than natural wood, Trex deck boards are made from:

• Recycled plastic film (like grocery bags)
• Reclaimed hardwood
• Chemicals that act as binders

These materials are mixed, extruded, and formed into deck boards to look like real wood. The most common styles mimic domestic hardwoods like cedar, redwood, and teak.

Trex decks are popular because they offer benefits like:

• Resistance to moisture, rotting, and insect damage
• No splintering
• Low-maintenance cleaning
• Durability and longevity
• Vibrant and consistent color tones

However, Trex is not maintenance-free. It still needs occasional cleaning to look its best. Over time, Trex decks collect dirt, pollen, leaves, spills, and other gunk. Mold and mildew can also grow on the surface.

Regular cleaning is recommended every 6-12 months to prevent buildup. Power washing is one effective cleaning method allowed for Trex decks.

Can You Pressure Wash Trex Decking?

Yes, you can use a power washer to clean Trex decks. Trex states that power washing is safe when done properly at a moderate pressure under 3,000 PSI.

Higher pressure levels or improper technique can potentially damage the decking. But a light pressure wash helps clear away surface debris and refresh the appearance. It’s also faster and more effective than scrubbing by hand.

Power washing works because grime and dirt accumulate mainly on the surface. Trex decking is waterproof and stain-resistant, so messes don’t absorb deeply into the material. A good rinse removes most accumulated buildup.

Plus, power washing can help inhibit mold growth. The high-pressure spray blasts away spores on the deck surface before they take hold.

Overall, periodic power washing is a quick maintenance option approved by Trex. Just be sure to follow recommendations for PSI and proper form. Avoid blasting too close or focusing on one area for too long.

Recommended PSI for Washing Trex Decks

When power washing a Trex deck, Trex specifies using:

• 1,500 – 2,000 PSI
• Must be under 3,000 PSI

These pressure levels are forceful enough to clean debris but gentle enough not to damage the deck boards.

For comparison, here are typical PSI levels for different power washing tasks:

• Driveways, patios: 3,000+ PSI
• Brick, stucco: 1,500 – 2,000 PSI
• Wood decks: 500 – 1,500 PSI
• Vinyl siding: Less than 2,000 PSI

As a composite material, washing requirements for Trex are similar to vinyl siding. The pressure needs to be high enough for cleaning action but low enough to avoid surface nicks, gouges, or scratches.

Ideally, choose a power washer with an adjustable PSI below 3,000 and use the lower settings for Trex. Gas-powered models often have higher max PSI over 3,000.

Electric vs. Gas Power Washers

For Trex decks, an electric power washer is the safer choice over gas models, for two reasons:

1. More consistent PSI control. Electric washers have better PSI adjustment, usually starting around 500 PSI. Gas models often exceed 3,000 PSI.

2. Less risk of damage. Electric wands tend to have wider fan spray nozzles. Gas wands have intense jet nozzles that must be held further away. An accidental close blast with a gas wand can damage Trex.

Look for an electric power washer with ~2,000 PSI max, multiple nozzles, and pressure adjustment. This makes it easier to control the PSI in the optimal cleaning range for composites.

Best Practices for Power Washing Trex

Follow these tips when power washing a Trex deck:

• Test first – Try a small, inconspicuous area before washing the whole deck. Ensure your settings clean effectively without damage.
• Remove furniture – Move any deck furniture, planters, and other items before spraying.
• Start with lowest pressure – Begin with 500-1,000 PSI and adjust as needed up to 2,000 PSI max.
• Use fan nozzle – Fan nozzles spread the pressure over a wider area. Avoid intense jet nozzles.
• Keep nozzle moving – Continuously move the nozzle across the deck surface. Don’t concentrate in one area.
• Work in sections – Wash a few boards top to bottom before moving on. Don’t allow the surface to dry while washing.
• Rinse with grain – When rinsing, run the nozzle perpendicular to the wood grain to prevent surface scratches.
• Scrub tough stains – For stubborn spots, pre-treat with a Trex approved cleaner before power washing.
• Wear protective gear – Wear goggles, gloves, closed-toe shoes, and other safety equipment.
• Let dry 1-2 days – Allow the deck to completely dry before replacing furniture or using again.

Proper form is also important. Hold the nozzle 6-8 inches above the deck surface at about a 45° angle. Work top to bottom on each board, overlapping spray paths slightly.

If you notice the surface getting damaged, stop work immediately and adjust to a lower PSI.

Always reference the Trex official guide to power washing for the most up-to-date recommendations.

Risks and Potential Damage from Power Washing Trex

Although an approved cleaning method, power washing does carry some risks for Trex decks. Potential damage includes:

• Surface nicks, gouges, scratches
• Peeling or splintering top layer
• Water spots or discoloration
• Mold/mildew growth in crevices
• Growth of biofilms if not fully rinsed

Surface damage mainly occurs from:

• Excessive pressure above 3,000 PSI
• Power washing too frequently
• Holding nozzle too close to the deck
• Power washing dirty/abrasive debris across the surface

To avoid damage, follow all the proper power washing guidelines covered in this article.

If discoloration or mildew occur after power washing:

• Make sure to rinse away all soap residues which can cause spots
• Follow up with a Trex-approved Brightener to restore an even color tone
• Treat any remaining mildew stains with a Trex Mildew Stain Cleaner

Alternatives to Power Washing Trex Decks

Power washing is the most effective way to deep clean a Trex deck and avoid needing to resurface too frequently. However, there are some alternative cleaning options to consider:

Soft wash

Soft washing uses chemicals and very low-pressure water. A mild oxidizing bleach solution can help break down organic stains without blasting the surface. Soft washing has less risk of damage when done properly. But results take longer compared to power washing.

Mild pressure wash

Some people “soft power wash” using a gas power washer at the lowest PSI with fan nozzle. This offers a bit more cleaning action than a soft wash alone. But you must be extremely cautious with this approach to avoid surface damage.

Trex cleaners

Trex makes special composite deck cleaners approved for its products. Using the recommended cleaners before and after washing helps enhance results. Some options are:

• Brightener – Restores color after washing
• Cleaner – Removes dirt, grime, and organic stains
• Reviver – Cleans and adds UV protection

Always check Trex.com for the latest cleaners compatible with your deck series. Avoid bleach or abrasive chemicals.

Scrubbing

For light dirt, you can scrub the deck using Trex cleaners, warm water, and a soft bristle brush. Scrubbing by hand takes more elbow grease but is very gentle. Be sure to scrub following the wood grain direction.

Rinsing

For quick maintenance, thoroughly rinse the deck with a garden hose. Avoid using high-pressure attachment heads which can damage the surface. The goal is just to wash away pollen, dust, leaves, and other debris before it builds up.

Conclusion

Power washing is an effective maintenance method for Trex decks when done properly. The key is using moderate pressure under 3,000 PSI, the right nozzle angle, and proper form to avoid surface damage.

Follow the recommendations in this article to safely power wash Trex and restore the beautiful appearance. Limit power washing to once or twice per year for routine cleaning. More frequent washing or excessive pressure can harm the deck over time.

For best results, combine power washing with a prep solution before and brightening cleaner after. This keeps the Trex deck looking like new with minimal effort.

Frequently Asked Questions

Can you pressure wash Trex Transcend decking?

Yes, Trex Transcend boards are power washable using the proper procedure. Transcend has a textured wood-grain finish and low gloss that hides scratches. But you still need to follow PSI limits and cleaning guidelines to prevent damage.

What PSI should I use to pressure wash composite decking?

For all Trex and other composite decking, use 1,500 – 2,000 PSI when power washing. Higher pressures above 3,000 PSI risk permanent damage to the deck surface. Always start on the low end and increase as needed.

How often should you pressure wash a composite deck?

Trex recommends power washing a composite deck once or twice per year at most. More frequent washing can gradually damage the surface. Spot clean stains in between with soap and water or a mild Trex cleaner.

Can you use a pressure washer on Trex Escapes decking?

Yes, Trex Escapes is a PVC-capped composite that can be pressure washed. Use maximum 1,500 PSI and follow other guidelines to prevent scratching or peeling the protective cap.

What should you not pressure wash?

Avoid power washing fragile materials like roof shingles, vinyl siding, or thin wood. Also use caution when power washing stained wood surfaces, clay or concrete products, older composite decks, and delicate plants or landscaping.

Power Washing Trex Decks: Summary Table

Guideline	Recommendation
PSI Range	1,500 – 2,000 PSI max
Nozzle Type	Fan nozzle, 25-45° wide spray
Distance from Surface	6-8 inches
Cleaning Motion	Gentle back & forth, overlapping strokes; rinse with wood grain
Chemical Cleaners	Use Trex recommended cleaners before/after
How Often?	1-2 times per year max

Conclusion

Power washing is generally safe for Trex decks when done properly at moderate pressure under 3,000 PSI. Always reference the manufacturer’s recommendations for your specific deck series. With the right pressure washing approach, you can safely restore the beautiful look of your Trex deck.