How to Remove Green Algae from Wood Deck

  • August 9, 2019
  • / By Dale Keese
Summer House Exteriors

After a long and wet period during which you couldn’t use your wood deck as much as you would have liked, it can be annoying to step out and see that your deck doesn’t look as good as you thought. If you don’t take care of the wooden areas regularly, it is very easy for the deck to develop unwanted mold and green algae.

Summer House Exteriors

This algae doesn’t just look bad to the human eye, but it can also be a health hazard as it makes the deck slippery and exposes people to the risk of falling as they try to walk around the deck.

If you are wondering how to remove green algae from a wood deck, you have come to the right place. While it can seem like an uphill task when you first start, you just need some basic good quality equipment and a few hours of your day to restore your wood deck to its former glory. More importantly, you need a good understanding of the steps that need to be followed for the best possible end results.

Here, you will be able to gain access to this brief primer that will first talk about the things you need before you start cleaning, and finally, the process involved.

If you step out of the house and notice that algae have taken over your deck, the first thought that crosses most homeowners’ minds is how to remove green algae from their wood deck. The process is very simple, but before you get started, there are some basic things that you need to collect. This will prevent any wastage of time when you are in the middle of the process.

Cleaning Bucket with Soapy Water

The most important of these are mentioned below, but you can edit this list according to your individual preferences:

  • Broom
  • Water
  • Bucket
  • Some protective gear like rubber gloves
  • Oxygen bleach
  • Acid or bleach-based deck cleaner
  • Deck sealer
  • Scrub brush
  • Garden hose

Step-By-Step Guide for Removing Green Algae from Your Deck

Algae are basically just a collection of microscopic plants that grow where sunlight and water are readily available. While algae are most common in water sources, it can also grow on your deck, especially in cases when the wooden deck has remained wet for a long period of time.

As these organisms are very hardy, they can sustain themselves through a wide range of climatic conditions. If you are wondering how to remove green algae from the wood deck, there are some instructions that you must follow closely. These are listed below.

Step One — Clear the Deck of Furniture

The first thing that you need to do when you are looking to remove green algae from your deck is to move all the furniture that is lying around on the surface. In order for the deck to be cleaned well, all your deck chairs, tables, swings or any such furniture or fixtures need to be removed from there and kept somewhere safe, away from the materials that you are going to use during the process.

The acid or bleach-based cleaner can cause some longstanding damage to all the furniture that you have outside if you let it remain there while you clean.

Step Two — Sweep Debris off the Surface

In order for the cleaning of the deck to be thorough and effective, it is important that the surface has been prepped well for the materials that you are going to use on it. If the deck has been out of use for a while, it is probably going to have a lot of leaves, gravel, and other extraneous elements just lying around. You need to use the broom – mentioned in the list above – to sweep the entire deck vigorously. This will ensure that a large amount of dust and dirt is removed before you start.

Wood Surface Debris

Step Three – Make Solution with Bleach

In the bucket that you have brought earlier, add warm water, so that almost ¾ of it is covered. To the water, you will be required to add two cups of high-quality oxygen-based bleach. You need to be very careful when you are dealing with chemicals like bleach, so make sure that you have enough protection in the form of rubber gloves and other things that you need.

Step Four – Time to Scrub and Rinse

Once you are sure that you have adequate protection, you need to get your hands on a good-quality scrubbing brush and use the bleach solution to move across the deck as you scrub the surface vigorously. This is a very important step and the bleach solution needs to be given some time – usually between 10 and 30 minutes – to start working. This is the chemical that will kill all the green algae and mold that has built up across your deck surface. Once you are sure that you have given it enough time, rinse the entire surface with the help of a garden hose.

Step Five – Pull out the Deck Cleaner

Once you are done with the bleach, you will have to use a specialized deck cleaner to do a more in-depth cleaning of the wood deck. These cleaners are usually based on acid or bleach, so you can check which one suits your needs best.

Most of these deck cleaners have to be mixed with some amount of water before you can apply it to the deck, so be sure to read all the instructions very carefully before applying. It should be allowed to set in for a while so that all the algae can be killed. Use the scrub brush again and give the deck a thorough cleaning.

Dog Playing with Garden Hose

Step Six — Rinse Well

Once you are satisfied with how clean your deck is looking, it is time to use your garden hose to give it a good rinse. This will be helpful in removing the cleaners and bleach, which can cause a good amount of damage if they are just left there. It is important to ensure that all parts of the deck and nearby areas are hosed down so that there is no cleaning solution that is left around.

Step Seven — Sweep the Deck

Pick up your broom once again and sweep well, so that there are no product or water pools left around on your deck. If there is water left around on the deck, it will act as a breeding ground for algae all over again. Once the water pools and puddles have been swept away, you can just air dry the entire deck.

Step Eight – Consider Deck Sealers

A good deck sealer can be a savior for people who want to keep their deck as good as new and avoid the growth of mold, mildew or algae on the surface. Most good quality deck sealers also provide UV protection.

Outdoor Rocking Chair

Step Nine – Set up Your Deck

If you have sealed your deck after cleaning it well, it is time for you to set it up again. Ensure that the deck is completely dry before you start placing all the furniture and other fixtures back on the deck and enjoy your summer out in the sun!

If you were wondering how to remove green algae from the wood deck, the process has been simply outlined for you to follow. Just make sure that you keep the deck clean and prevent any such buildup in the future!