Turn your garden hose on full spray and wash any dirt and grime off the brick as best you can with the strong force of the hose spray. Work methodically from one side to the other so that it doesn’t keep spraying back onto a part you have already cleaned.

You may also use a bucket with soapy water to scrub stains off of exterior red brick.You can use different hose settings to access some of the harder to reach places. For example, you might need a more steady stream to get rid of cobwebs hiding in corners and crevices.
 Make a cleaning solution using four parts water to one part bleach. Combine it all in a bucket. Scrape off any moss or mold with a spatula or a stiff-bristled brush. Apply a generous covering of the bleach mixture directly to the red brick and let it sit overnight. Then you can rinse off the bleach mixture with a hose.If there are still traces of mold remaining, you can make a stronger mixture – half water and half bleach – and let it sit on the red brick for two days before rinsing it off.
 Once you have finished cleaning your exterior red bricks, consider sealing them with a siloxane- or silane-based sealer. This will help protect your bricks from future stains, and it will prevent dirt and grime from building up on your bricks over time.You should be able to purchase these products at any home improvement store.
Use a hose to wash off dirt and debris.
Apply a bleach mixture to eliminate moss and mold.
Seal the bricks for future protection.
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