How to clean mold fungus and dirt from your exterior vinyl siding

If you own a home with vinyl siding the maintenance factors are pretty low in comparison to other options like brick, stone and light weight artificial stone products. Vinyl is produced to last your home about 30 years give or take and the amount of time that it will last depends on how well you keep it clean and the UV Rays that break it down over time.

If you are like most home owners you are likely to have a buildup of dirt and fungus that can make your home look pretty ugly. Fungus or mold will normally attach to your siding in the wet season however it won’t ever go away until you remove it.

When fungus first appears it looks bright green like grass and after it dies it takes on a dark black appearance. At first you might think that it is soot from vehicles or general pollution and there might be some of that mixed in but the problem with organic matter of this type is that you can risk it migrating into your interior walls if you don’t catch it early.

Once organics like mold and fungus gets into your plywood or interior drywall you will be looking at some serious out of pocket expense to repair the damage not to mention the health conditions in your home could turn dangerous.

Cleaning your home’s exterior from fungus and mold

The cleaning process is relatively simple and you can expect to spend about a half a day for an average home. The best methods are the simplest and the cost for materials and equipment is pretty low.

If you live in a single story home you can normally do all of the work yourself but if you live in a two story home you might want to hire a contractor if you are afraid of or unable to climb a ladder to reach areas that aren’t easily accessible from the ground.

To do a full job you want to treat your whole home if needed however most of the time you will not need to treat your roofing shingles unless they show visible signs of contamination. This means at the minimum you will want to treat your gutters, siding and all of the flashing.

A ladder probably will be necessary to reach peaks of sidewalls however you may be able to use a pressure washer if it allows you to attach a chemical concentrate bottle.

Personally my method is to use a garden sprayer that you would normally use to spray weeds however I have a separate one that is used only for the home. Even though there would only be a very tiny amount of herbicide or pesticides remaining in the tank after rinsing it clean I don’t like taking the risk and the $15 cost of a two gallon pump up sprayer is not so much considering I know it will always be in good repair to use for cleaning the home once or twice a year.

In a two gallon sprayer I add enough water to bring it up very close to the top of the sprayer then I add about a third of a gallon of bleach and about a half cup of whatever liquid soap I have on hand. Grabbing a gallon of detergent at the dollar store is not a bad idea since it is cheap and all you are really looking for is soap that will add a small amount of thickness to your solution and a bit of suds. The bleach will do all of the work but adding the soap helps keep it on your walls so it won’t immediately run off to the ground.

My primary concern is normally the north and north west sides of my home however the front of my home sits to the east so it is important to get that side even if it is not quite as bad. Some years I won’t even need to do the southern exposure but I normally wash it down just to remove the loose dirt.

This solution works well on decks and concrete surfaces too.

Spray your home down starting at the top of the wall and working down. This will reduce the amount of chemicals you need to use because it will naturally flow down the side of the wall.

Bleach takes at least 15 minutes to begin working. Normally I will spray one side of the home and move on to the second. Each side normally takes about one 2 gallon container and after I have sprayed the second side I go back and look for changes in the fungus.

Bright green fungus will turn brown and black fungus will normally disappear to some extent.

Hit any areas that have dried or are stubborn a second time on the first side of the house and then move on to the third side of the home. When you are done the third side go back to the second side and look.

That is normally how I work. Spray one side and go back to look at the side you sprayed before that. It works well if you happen to have a little left over before you need to refill your tank.

You can also hit your walkways or even your patio furniture with that small left over amount.

It usually takes me about a gallon and a half or maybe two gallons of bleach to do our whole home and shed including the deck and whatever else seems to need it.

The best time to do this is just before a storm that way you aren’t wasting time and money hosing down your house. But it is important to go over your home with a high pressure hose attachment to remove the dirt.

Since it usually takes me an hour to get all the way around the house thats not a bad time to spray the house down with the hose but for best results I like to keep the bleach on the siding for a few hours and if I do it in the afternoon that means misting it to keep it wet. If I do it later in the day I might not wash the home down to remove the soap and bleach until the next morning. And if it rains it will mean that much less work.

Final Note

There are companies that make chemical cleaners and bleach can be pretty harsh on many surfaces so you don’t want to spray fabrics on awnings or outside furniture if you think you might have a problem. If the surface is vinyl, glass, painted or wood then it can normally stand up to a light bleaching solution that is 5 parts water one part bleach. You may find you need something stronger if your home has been neglected and my recommendation is to repeat this process after about a week.

Also very important to note you want to do this in your worst clothes because bleach will ruin your clothes and you will be spraying a lot of it.

Eye protection is a MUST and its a good idea to wear some rubber gloves.

Be careful on the ladder especially if the wall is wet and have someone monitoring you or at minimum keep a cellphone on you in case of an accident. That is good advice when working on any project have a phone on you or someone who will check on you ever few minutes.