Renu Cleaner

The Complete Guide to Cleaning & Prepping Outdoor Surfaces

Renu Cleaner Concentrate™ is the product this whole guide comes back to, so we'll say it up front: if you only remember one thing here, it's that almost every outdoor surface problem – mold, oxidation, dulled siding, a driveway that won't hold a sealer – starts with skipping the cleaning step. Sealers, stains, and restorers all perform better on a surface that's been cleaned first, not just rinsed off with a hose.

This guide covers why outdoor surfaces get dirty in the first place, how a proper cleaner concentrate works, and which surfaces need what kind of attention – siding, decks, shutters, concrete, patio furniture, all of it. By the end, you'll know exactly what your outdoor space needs before you ever pick up a sealer.

Why Outdoor Surfaces Get Dirty (and Stay That Way)

Outdoor surfaces don't just collect surface-level dirt. A few things build up over time that a garden hose alone won't touch:

• Oxidation. UV exposure slowly breaks down the top layer of siding, plastic, and painted surfaces, leaving that chalky, faded look.
• Mold, mildew, and algae. Shaded, damp spots – under eaves, behind shutters, along fence lines – are constantly growing something, even if you can't always see it yet.
• Grease and organic stains. Grill splatter, pollen, tree sap, tannins from nearby plants – all of them settle into porous surfaces like concrete, wood, and brick.
• General grime buildup. Years of normal weather exposure leaves a film that regular rinsing can't remove.

None of this is really about surfaces "getting old." It's residue and buildup sitting on top of a surface that's otherwise still in good shape – which is exactly what a proper cleaner concentrate is built to strip away.

How a Cleaner Concentrate Actually Works

An outdoor cleaner concentrate isn't the same as a jug of pre-mixed spray cleaner. Concentrates are formulated to be diluted, which means one bottle goes a lot further, and the cleaning strength stays consistent no matter how much surface you're covering.

Renu Cleaner Concentrate™ is bleach-free, and zero-VOC, so it lifts oxidation, mold, mildew, and algae stains without the harsh fumes or surface damage that stronger chemical cleaners can leave behind. One gallon covers roughly 1,500 sq. ft. and makes more than 5 gallons of usable cleaner once diluted – a little really does go a long way here.

Choosing the Right Outdoor Cleaner

Not every "outdoor cleaner" is built for the same job, so a few things are worth checking before you buy one:

• What surfaces it's rated for. Some cleaners are single purpose; others are genuinely multi-surfaced.
• Whether it's bleach-based or not. Bleach can discolor certain surfaces and kill nearby plants – worth knowing before you spray it near landscaping.
• Concentrate vs. ready-to-use. A cleaner concentrate costs more upfront but works out cheaper per gallon and takes up far less storage space.
• What you're prepping for. If you're planning to apply a sealer for concrete or any concrete sealer outdoor project afterward, the cleaner needs to fully strip the surface first – sealer applied over a dirty or oxidized surface won't bond properly, no matter how good the sealer is.

Different Surfaces & Their Cleaning Needs

Renu Cleaner Concentrate™ is genuinely multi-purpose, but different surfaces still call for slightly different approaches:

• Vinyl siding – the most common use case, tackling years of oxidation, pollen, and algae streaking that make siding look dull.
• Decks and composite decking – mold, mildew, and grease buildup that regular power washing alone won't fully lift.
• Shutters and trim – smaller surfaces that trap dirt in the grooves and corners, especially on faded vinyl shutters.
• Concrete, driveways, and patios – oxidation and stains that need to be removed before any sealed concrete floor or outdoor concrete sealer project.
• Brick and pavers – porous surfaces that hold onto grime longer than smooth ones.
• Patio furniture – a patio furniture cleaner needs to handle sun fading and outdoor grime without damaging finishes or fabric.
• RVs, campers, and auto surfaces – not something people expect from a house-wash cleaner, but the same oxidation-removal power applies here too.

This is why Renu Cleaner Concentrate™ works as well on a fence as it does on a driveway – it's not just for vinyl and shutters, it's built to handle whatever exterior surface needs it.

Why Pre-Cleaning Before Sealing Matters

This is the step people skip most often, and it's the one that determines whether a sealer actually performs the way it's supposed to.

Sealers – whether it's a deck sealer, a concrete sealer outdoors, or anything else – need to bond directly to the surface underneath. Dirt, oxidation, and old residue sit between the sealer and the surface, which means the sealer ends up bonding to grime instead of the material itself. That's a big part of why a composite deck sealer and a composite deck cleaner aren't interchangeable – cleaning and sealing are two separate steps doing two separate jobs, and skipping the first one undercuts the second.

Renu Cleaner Concentrate™ was built specifically as that prep step – a great first move before sealing driveways, patios, and walkways with any concrete sealer, or outdoor sealer product.

Product Spotlight: Renu Cleaner Concentrate™

Here's what's actually in the bottle and what it does:

• Removes oxidation from siding, plastic, and painted surfaces
• Lifts mold, mildew, and algae stains
• Keeps surfaces clean for 3+ years after a proper treatment
• 1 gallon covers approximately 1,500 sq. ft., and makes more than 5 gallons once diluted
• Bleach-free, zero-VOC – safe for use around landscaping and pets
• Multi-purpose – works on siding, decking, brick, pavers, cement, and more, not just vinyl

It's available as a standalone concentrate in quart, gallon, and 5-gallon pail sizes, or as the Renu Cleaner Concentrate™ Easy Clean Kit, which bundles a gallon of concentrate with a drill brush attachment, gloves, and a free sample of Vinyl Renu.

Related Products Worth Knowing About

A few other products in this lineup pair naturally with a good cleaning routine:

• Composite Deck Armor™ – the sealing step that follows once a composite deck has been properly cleaned, keeping mold and algae from coming back for 3+ years.
• Shutter Renu™ Shutter Restorer – built specifically for restoring faded vinyl shutters once they've been cleaned.
• Vinyl Renu sample – a low-commitment way to test how well faded vinyl siding responds to restoration after a Renu Cleaner treatment.

How to Use Renu Cleaner Concentrate™

The process is simple by design:

1. Dilute the concentrate according to the surface you're treating – tougher jobs (heavy oxidation, deep stains) call for a stronger mix than routine cleaning.
2. Apply and let it work. Spray it on and give it time to break down oxidation, mold, and grime before rinsing or scrubbing.
3. Scrub where needed. The included drill brush attachment (in the Easy Clean Kit) takes most of the elbow to grease out of stubborn spots.
4. Rinse thoroughly. A clean water rinse removes the lifted residue along with the cleaner itself.
5. Let the surface dry fully before applying any sealer, stain, or restorer on top.

Common Mistakes

A few things that undercut results more than anything else:

• Skipping the cleaning step entirely and sealing straight over a dirty surface
• Using a bleach-based cleaner near landscaping or on surfaces prone to discoloration
• Not diluting concentrate properly – too weak wastes time, too strong can be harder to rinse clean
• Rinsing before the cleaner has had time to work
• Sealing before the surface is fully dry

Maintaining Clean Outdoor Surfaces

Once a surface has had a proper deep clean, keeping it that way is a lot easier:

• Routine light cleaning between deep treatments keeps buildup from setting in as heavily.
• A yearly or seasonal Renu Cleaner treatment keeps most surfaces looking refreshed without needing a full restoration each time.
• Reapplying sealer on schedule matters too – a clean surface with an expired seal will still show wear faster than it should.

Conclusion

Cleaning gets treated as an afterthought, but it's really the step that determines whether everything applied after it – a sealer, a stain, a restorer – holds up. A properly cleaned surface is the difference between a sealer that lasts years and one that starts failing within months.

If your siding, deck, patio, or driveway hasn't had a really deep clean in a while, Renu Cleaner Concentrate™ is the place to start before anything else goes on top.

Frequently Asked Questions

Is Renu Cleaner Concentrate™ safe for use around plants and pets?
Yes. It's bleach-free, zero-VOC, and non-toxic, making it safer to use around landscaping and pets than harsher chemical cleaners.

What surfaces can I use it on?
Siding, decking, brick, pavers, cement, stucco, wood, composite, metal, and even RVs, campers, and auto surfaces.

Do I need to rinse it off?
Yes, always rinse thoroughly after it's had time to work – this removes both the cleaner and the residue it lifted.

How is this different from a pressure washer alone?
A pressure washer moves dirt around with water pressure. A cleaner concentrate chemically breaks down oxidation, mold, and stains first, so what comes off actually stays off longer.

Can I use this before applying a sealer for concrete?
Yes – it's specifically recommended as a prep step before sealing driveways, patios, and walkways with any concrete sealer outdoor product.

How long does one bottle last?
Because it's a concentrate, one gallon makes more than 5 gallons of usable cleaner, so it covers significantly more surface area than a similarly priced ready-to-use spray.

Will it work as a patio furniture cleaner too?
Yes – its multi-surface formula handles the oxidation and grime buildup that patio furniture accumulates from sun and weather exposure.