The Ultimate Guide to Cleaning a Composite or PVC Deck
You've just made a significant investment in a new deck for your backyard and you decided to go with composite or PVC decking because you believed it was "no-maintenance", meaning that you would never have to sand, stain or paint it. When it comes to composite and PVC decking, this is true and many top decking brands like TimberTech/AZEK and Deckorators, even have 25 or 50-year Fade & Stain Warranties. But this does not mean that your new deck will not require regular cleaning, in the same way your car needs regular cleaning so that the look and quality of it will not deteriorate. And while decking brands offer a warranty against staining, it's important to point out that these are "limited" warranties and will not cover you if, for example, you spill wine on your deck and you fail to clean it up in a timely manner (typically within 7 days!) or if you allow tree sap to soak into your deck.
Also, maybe you have had your composite or PVC deck for some time now and you notice that the color is fading. If you haven't been doing regular cleaning of your deck, this will undoubtedly be due to the buildup of dirt and grime on the deck surface which a good cleaning will cure.
So how do we maintain, that is, clean, our composite or PVC deck? The following article breaks down deck maintenance into the following areas:
Periodic & Spot Cleaning - What you can do to regularly clean your deck including removing tree sap.
Yearly Cleaning - How to perform a yearly Quick Cleaning, Deep Cleaning, or Ultra Deep Cleaning of your deck.
Winter Maintenance - This to consider for the winter.
Periodic & Spot Cleaning
General & Periodic Cleaning
In order to keep your deck looking clean and to avoid having to do too much work when doing your yearly spring cleaning, it's best to do the following regularly:
Periodically sweep dirt, debris, dust, and pollen off your deck surface.
Periodically sweep leaves off the surface of the deck. Leaves left on the deck for an extended period of time may cause mold to build up on the surface.
Remove any tree sap ASAP. See instructions below.
Use a garden hose or simply a cloth, to clean paw prints, mud, or other tracked material soon after they appear.
Wipe up any small spills that might occur when outdoor entertaining, such as wine spills. Waiting longer than 7 days to wipe up stain-causing spills may void the manufacturer's warranty.
Clean up oil, grease, and food spills as soon as possible to prevent staining.
Keep a large rubber or outdoor mat under the barbeque to prevent regular grease splashes from reaching the deck surface.
Remove any mold and mildew as soon as possible to prevent it from spreading. See "Spot Cleaning" below.
Cover your deck with the appropriate cloth or another porous cover when working with cement, stucco, motor oil, or paint to protect the deck surface.
Spot Cleaning
There are times when you have a small area of the deck that needs more than just a simple wipe with a cloth or a rinse with the garden hose. Maybe you have a small area of the deck that has been ignored and has accumulated some dirt and grime, or maybe you have some mud spots that were left too long or you had a raccoon leave their mark in the corner. These are situations where you will need to use a brush to clean. Follow these steps:
Tools and materials required:
Dawn dishwashing liquid.
Deck brush such as this one. (With or without an extended handle)
Bucket (optional)
Garden hose
Step 1: Wet the area to be cleaned with the garden hose.
Step 2: Fill a bucket with water and add Dawn dishwashing liquid OR simply squirt a small amount of Dawn directly onto the wet area to be cleaned. You just need enough soap to get a decent amount of suds.
Step 3: Use the deck brush to scrub the soap into the area to be cleaned. Do not use a lot of pressure. Firm brush strokes should be enough.
Step 4: Use the garden hose to THOROUGHLY rinse the area.
Step 5: Repeat steps 2 to 4, if needed.
Removing Tree Sap
In cases where you have dreaded tree sap land on your deck, its best to attack it ASAP although sap stains can be very aggressive stains and as such there's no guarantee of removal. However, you can try to use ONE OF the following procedures in an attempt to either remove or minimize the stain:
OPTION 1: Use warm, soapy water to start. Using a mild, liquid dish soap such as Dawn, add one strong squirt to every liter of warm water. Use warm or hot water in order to help soften the sap. Use a soft new sponge or deck brush to lightly work and loosen the stained spot. When clear, rinse off the area with a hose and allow to try before trying again if needed.
OPTION 2: Try a cleaner such as "Goo Gone". First test it in an inconspicuous area by very lightly scrubbing the area and checking often for discoloration. If safe, try applying the cleaner directly to the sap and use a deck brush to brush it off maintaining a light, scrubbing motion. Rinse with a hose and repeat if necessary.
OPTION 3: If you have large drops of tree sap, place ice in a sealed bag and set the bag over the sap area. Leave on for 20 to 30 minutes. The idea is to get the sap to harden. Once hardened, use a putty knife to very gently lift or chip off as much of the sap as possible being very careful not to gouge or cut the composite decking.
Yearly Cleaning
Don't we all love spring cleaning! Well here is one more task to add to your spring cleaning routine that will help your composite or PVC deck to maintain a long lasting glow and get it ready for you to enjoy through the upcoming spring, summer and fall. If you do this cleaning routine yearly, or you just don't have that much dirt, grit and grime on your deck, you can use the Quick Cleaning Method below. If you missed a year and you find that your deck could use a really good cleaning, then use the Deep Cleaning Method. But if you have missed a few years or your deck has accumulated a lot of dirt, grit and grime, skip right to the Ultra Deep Cleaning Method.
Quick Cleaning
The quick cleaning method simply involves the use of a pressure washer, with or without soap attached. If you choose to use soap in the pressure washer's soap dispenser, then you will make two passes: one pass to spray the soap on the deck and the next pass without the soap to thoroughly rinse the deck.
Key points to keep in mind when using a pressure washer on your composite or PVC deck:
Never use more than 1500 psi. While some manufacturers allow a higher PSI, you almost never need to go higher than 1500. It's better to be safe than sorry with the surface of your deck.
Always use a fan tip nozzle. This avoids a concentrated spray that can damage or score your deck.
Always go WITH the grain and direction of the board in a sweeping back and forth motion.
Always keep the nozzle 6-8 inches above the deck surface.
Deep Cleaning - Simple 5 Step Process
Deep cleaning involves the use of a garden hose, a bucket, a deck brush and soap to give the deck a good scrub with soap and water.