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How to Clean a Galvanized Metal Roof

how to clean a galvanized metal roof

Do you want to know how to clean a galvanized metal roof? If so, then you have come to the right place.

In this blog post, we will be discussing three different methods of cleaning a galvanized metal roof that can help get it looking like new again.

We will also provide an overview of the process and some things that need to be taken into consideration when using these methods.

So, if you are interested in learning more about how to clean a galvanized metal roof, keep reading!

What is a galvanized metal roof?

A galvanized metal roof is a roof that is made of some form of sheet steel that has had zinc applied to the surface.

This creates an extremely durable material with low maintenance while also protecting it against rust and corrosion while still supporting the natural beauty of the steel beneath, rather than covering it up like paint or another material might.​

Why would you need to clean a galvanized metal roof?

Galvanized metal roofs can accumulate a great deal of dirt and moss over time. Moss growth causes green stains on the roof.

Snow blowing off from trees can additionally cause dirt and other environmental pollutants to land and accumulate on your roof.

The best way to clean a galvanized metal roof is with caustic soda (lye) or sodium hydroxide (caustic potash) and a professional grade pressure washer.

Washing your roof with the wrong chemical can cause staining as well as damage to the galvanize coating of the metal roof.

Cleaning with too low of a concentration will not remove all stains or debris from the metal.

Cleaning with an excessively high concentration of the wrong cleaning solution can cause damage to the metal surface.

What are the Methods for cleaning a galvanized metal roof?

There are various ways to clean a galvanized metal roof. The selection of your method will depend on the season, available equipment, and desired result.

Some methods include the use of high-pressure washers, low pressure washing machines, acid wash, bleach solution or hand scrubbing with a cleaning brush.

Reminder: A few tips before you start

Be sure to wear protective clothing, including rubber boots, glasses, and gloves. Also make sure that other family members are out of the area while you are working.

Spray cleaning machines should only be used when all safety precautions have been followed.

Be especially cautious with ladder safety as well as electrical safety. Read the manufacturer’s instructions in full before using any machinery.

Low cost way to clean a galvanized metal roof?

It’s easy to clean a galvanized metal roof using the following, inexpensive items: one gallon of water, one cup of bleach and a scrub brush.

Mix the solution in a bucket and apply with a scrub brush working from the top down. Rinse well as you work from bottom to top. Be sure that you do not breathe any of the fumes.

*** If you are using bleach, be sure to test for colorfastness on an inconspicuous area before you begin.

Maintaining your galvanized metal roof is important! Keeping it clean will reduce rusting and increase its lifespan.

Although many people simply pressure wash these roofs, this can lead to damage and an unsightly appearance.

How to clean a galvanized metal roof with bucket and scrub brush method

Step 1 – Prepare all your necessary tools and materials, having them on hand before you begin will make the project go much more smoothly.

You’ll need a five-gallon bucket with a snap on lid, a sponge or a rag mop, liquid dish soap, a scrub brush, water, and a pair of gloves.

Step 2 – Fill the bucket about halfway with warm water and add a squirt of dish soap to it. Mix well with your gloved hand or a sturdy wooden spoon.

You can use another type of soap if you wish, but be sure that it is not one that will produce a lot of suds as the suds will only stick to the galvanized metal, creating a slippery and dangerous surface.

Step 3 – Dip your scrub brush into the soap water and begin scrubbing away any dirt or debris on your roof.

This is going to be a backbreaking task so make sure you have everything you need near you before you begin.

Keep a steady pace while doing the cleaning, but don’t scrub too hard or be rough with your galvanized roof as this may damage it.

Step 4 – Once your roof is clean and dry, add another squirt of dish soap to your bucket along with some water.

Mix well and use the rag mop to wipe down the entire surface of your roof, removing any leftover residue or dirt.

Step 5 – Finally, take off your gloves and hang them on the handle of the bucket. Snap on the lid and store it in a safe place until you need it next time.

Wipe off any excess soap from the top of the bucket before storing it, leaving the lid off for a while until everything dries thoroughly.

Another option is Pressure Washing

Pressure washing is an excellent way to remove the green growth, moss and general dirt that can accumulate on your galvanized metal roof.

However, you should always start by brushing off any loose debris before pressure washing.

You will need to use a high-pressure washer nozzle at least 40 degrees in tip measurement to clean your roof properly.

This will ensure that you do not damage the surface of your roofing material which can be an issue if you use overly aggressive pressure washer techniques.

The pressure washer will remove most of the grime and dirt on your roof, but it may not be able to get rid of all of it.

That is why you should always follow up with a power wash after using a pressure washer so that any stubborn spots can be easily removed.

Steps to clean a galvanized metal roof with power washer method

1. Turn off power source to the roof or hot water heater, etc.

2. Ensure sufficient pressure washer supply with area marked out at least 5-feet from edge for safety of material and persons involved in cleaning process

3. Always work from a ladder as close as possible to the surface being cleaned is crucial for safety reasons.

4. Always use high-pressure washer nozzle of a 40-degree tip for exterior cleaning of galvanized metal roofing or gutters to avoid damaging the metal surface while removing dirt and debris.

Running water at this pressure will be strong enough to cut through the dirt and grime without compromising the integrity of your roofing system.

5. Start at the bottom edge of the roof by moving across to avoid missing areas.

6. Always use an S pattern to move back and forth, rather than circular motions over your metal building material. The latter can cause damage as you rub over it continuously.

7. Work your way up the roof to avoid back strain and potential injuries to your feet, legs, hips, and spine. Always opt for a stable ladder to keep you safe while working on the roof at an angle.

8. Switch off pressure washer whenever moving to another area or height of your roofing system.

9. Wait a couple of hours after pressure washing to allow your roofing system to dry before going on the roof again.

10. Apply a metal protectant with UV protection after cleaning galvanized metal roofs, which will prevent future oxidation and damage from occurring as well as keeping it looking fresh and new for longer.

Final Thoughts

Whichever method you pick, you can be sure of one thing – cleaning your galvanized metal roof is a lot easier when you have the right tools, materials, and equipment for the job.

Before making any moves towards cleaning your galvanized steel roof, make sure to put on protective gear like rubber gloves and safety goggles.

Safety glasses are also advised to ensure that debris doesn’t fly into your eyes while you are working.

If there is any moss growing on the roof, it will first need to be scraped off with a flat shovel or trowel. Do not use chlorine bleach as it can damage the metal.

After scrubbing and hosing down the roof one more time, apply a sealer containing protection from UV rays.