Armor AR350 vs AR500

1. The Short Answer: It Comes Down to Sheen

Foundation Armor describes the AR350 as a solvent-based low gloss pure acrylic sealer and the AR500 as a solvent-based high gloss pure acrylic sealer. Both are built to seal, darken and protect concrete and concrete pavers, both are marketed for driveways, walkways, patios and pool decks, and both leave a surface film rather than soaking in. If you lay the two technical data sheets next to each other, the only line in the technical information block that changes is the dry appearance: low gloss for the AR350, high gloss for the AR500.

That matters because a lot of what gets written about these two products assumes the AR500 is the heavier, higher-solids sealer and the AR350 is the lighter one. The current data sheets do not support that. Both list solids at 25 percent, both claim up to 175 square feet per gallon per coat on porous surfaces and 200 to 225 on smooth, prepped ones, and both carry the same drying, recoat and traffic times. The number in the name is not a solids rating you can compare, so do not buy the AR500 expecting a thicker or longer-lasting film on the strength of the bigger number.

What you are actually choosing between is a satin-style wet look and a glossy wet look. Both will darken the concrete in the same way, and Foundation Armor uses near-identical wording for each, warning that the sealer will dramatically darken and enhance the colour of the substrate. The AR500 then adds a more reflective surface on top of that colour change. On a smooth, well-coloured stamped pattern that reflection can look spectacular. On a broom-finished driveway it can look like a plastic coating, and it makes every scuff, tyre path and patch of uneven absorption easier to see.

So the decision is less about protection and more about appearance and safety. If the surface is walked on wet, sits in full sun, or has a rough texture meant to look like natural stone, the AR350 is the easier product to live with. If the surface is smooth, under cover or mostly decorative, and you want maximum shine, the AR500 is the one built for that. Our full Armor AR350 review goes deeper on the low-gloss version; this page sticks to the head-to-head.

2. AR350 vs AR500 Spec Sheets, Side by Side

Every figure in the table below comes from Foundation Armor's own technical data sheets and product pages for the two sealers, as published in 2025. We have not lab-tested either product, so treat these as the maker's ratings rather than independent measurements. Where the maker gives a range, we have kept the range rather than picking a flattering end of it.

Twenty-five percent solids means that a quarter of what is in the can stays on the slab as acrylic once the solvent evaporates. That is a middle-of-the-road figure for a solvent-based acrylic, and it is the same for both products, which is why the coverage and recoat figures match. A practical consequence is that the AR500 will not build a thicker protective layer per coat than the AR350. If you want more film, you get it the same way with either product: a second coat, applied thin, 24 hours after the first.

The coverage figures are per coat, and Foundation Armor suggests two coats for an even appearance. On a porous broom-finished slab that means budgeting for roughly 85 to 90 square feet per gallon across both coats, and on a dense, smooth surface closer to 100 to 110. Exposed aggregate and older, open pavers drink more than the label rate. Our guide to how much concrete sealer you need walks through the maths, and it applies to both of these products identically.

The VOC choice is the one spec that genuinely changes how the product behaves in your hands, and it applies equally to both. Foundation Armor sells each sealer in 50, 350 and 700 g/L versions. The maker says the 50 VOC formula can be used in all 50 states, the 350 VOC formula in every state except California, Colorado, New York and Ohio, and the 700 VOC formula is barred in 19 states plus DC. It also warns that the 50 VOC version has significantly reduced working time, so you need to work fast in small sections and keep the roller saturated. Order the version that is legal where the slab is, not where the warehouse is.

Both come in a 16-ounce sample, a 1-gallon bottle, a 5-gallon pail and a 55-gallon drum, with a stated shelf life of up to one year when properly sealed and stored. The maker also notes that the 350 and 50 VOC versions ship as hazardous materials and cannot be returned, which is a strong argument for buying the sample size of each and testing them on your own slab before committing to pails.

3. Low Gloss vs High Gloss: What Changes on the Slab

Both sealers produce what the industry calls a wet look: the colour of the concrete darkens and deepens, as it does when it rains. That darkening is a property of the solvent-based acrylic soaking slightly into the surface and wetting out the pigments and aggregate, and the two products are described as doing it equally. What differs is the light coming back off the cured film. The AR350 leaves a soft, satin-like sheen. The AR500 leaves a reflective, glassy surface that can mirror light from a low angle.

On stamped concrete the sheen interacts with the texture. Our stamped concrete sealer guide makes the point that satin finishes generally look the most authentic on rough patterns meant to imitate natural stone, because real flagstone and slate have a low-lustre surface, while high gloss can look excellent on smooth patterns such as ashlar slate or large-format tile. That is the clearest way to split these two products for a stamped job. A textured fieldstone or cobble pattern usually suits the AR350. A smooth, crisp pattern with strong colour and antiquing release often looks best under the AR500.

Gloss also changes what the eye picks up. A high-gloss film is unforgiving of anything uneven underneath, whether that is a repair patch, a slightly blotchy colour, a lap mark from the roller or a traffic lane where the sealer has worn thinner. Foundation Armor warns on both data sheets that stains, cracks, crazing and other issues can be enhanced by a wet look sealer, and that warning lands harder with the AR500. If your slab is not in good cosmetic shape, the AR350 hides more.

Expect the gloss to vary by surface. The maker says that on porous pavers the gloss level may be reduced and more material may be needed to reach the desired finish. In other words, a first coat of AR500 on thirsty pavers may not look high gloss at all, and a first coat of AR350 may look almost flat. Do not judge either product from one coat on an open surface, and do not keep adding coats to chase shine; too much acrylic is what causes the bubbling and clouding problems covered in the mistakes section below.

Finally, consider the plain broom-finished slab. Foundation Armor strongly suggests a test area first on any surface without colour variation, such as broom-finished concrete, so you can see whether you actually like the wet look on it. Grey concrete with a high-gloss film is a look some people love and many regret. The 16-ounce samples exist for exactly this decision: seal a square metre with each in an inconspicuous corner and look at it wet, dry, in full sun and at dusk before you buy.

4. Slip Resistance: The Bigger Practical Difference

Both data sheets carry the same warning: the product, when cured, may be slippery when wet, and Foundation Armor suggests a non-slip additive where slipperiness is a concern. That is true of every film-forming acrylic. The film fills the fine texture that normally gives a shoe something to grip, and water sitting on a smooth film acts as a lubricant. Neither sealer is safe on a wet walking surface without grit.

The difference between them is a matter of degree rather than a published figure. Foundation Armor does not publish slip-resistance ratings for either product, so we will not invent one. As a general principle, though, a glossier and smoother film offers less micro-texture underfoot than a satin one. That makes the AR350 the safer default anywhere bare feet, wet shoes or elderly visitors are a regular feature, with grit added either way.

Foundation Armor sells its own Armor Non-Slip additive in ultra-fine, fine and coarse grades and says all three work best in these sealers. The ultra-fine grade is drill-mixed into the sealer at 3 to 6.5 ounces per gallon before application. The fine and coarse grades are broadcast onto the second coat with a spreader and then back-rolled to lock them into the film. The coarser the grade, the more grip and the more visible texture, so most residential patios end up with ultra-fine or fine.

For pool surrounds specifically, the decision is close to made for you. A high-gloss acrylic around water is the configuration most likely to cause a fall, and the extra reflectivity also adds glare in full sun. If you want an acrylic on a pool deck, the AR350 with non-slip is the sensible starting point, and our pool deck sealer guide covers alternatives that leave no film at all. The same logic applies to steps, ramps and sloped walkways, where a slip has further to go.

5. Which Surfaces Each One Suits, and Where Neither Belongs

On paper, both sealers are approved for the same surfaces: poured concrete, stamped concrete, exposed aggregate and concrete pavers, inside and out. Foundation Armor lists driveways, walkways, stairs, pool decks, patios, carports and pole barn floors as typical uses for both. So the AR350 or AR500 for stamped concrete question is not about compatibility; either will bond to clean, unsealed or solvent-acrylic-sealed stamped concrete. It is about the finish you want and how hard the surface is used.

Driveways are where the AR350 earns its place. Tyres scuff acrylic, and both data sheets say the product does not stop tyre marks from forming and is not resistant to brake fluid, gasoline and many similar products. A worn lane under a low-gloss film is far less obvious than the same lane under a mirror finish. If you are sealing a stamped or coloured driveway with an acrylic, the AR350 is the more forgiving choice. If you are sealing a plain grey driveway mainly for protection, consider whether you want a film at all; our acrylic vs penetrating sealer comparison explains why a penetrating sealer often protects a salted driveway longer.

Covered and decorative surfaces are where the AR500 makes sense. A stamped porch under a roof, a carport, a pole barn floor or a feature patio that sees light foot traffic gets the visual payoff of high gloss without much of the wear and wet-slip downside. Foundation Armor rates both products at up to 2 to 7 years of life on interior surfaces against up to 1 to 3 years on exterior ones, which tells you how much weather and traffic shorten an acrylic's life.

Some surfaces are off the list for both. The maker says neither should be used on clay brick, red Chicago pavers, flagstone, slate or natural stone, and points buyers to its WL550 or SX5000 WB penetrating products instead; our Foundation Armor SX5000 review covers the latter. Neither should go on pavers laid over a concrete slab or concrete base, which the data sheets say leads to continuous blushing and delamination. And neither can go over a water-based acrylic, acrylic latex, paint, epoxy or urethane; they bond only to bare concrete or to an existing solvent-based acrylic.

Age matters too. Both data sheets say the concrete must be a minimum of 28 days old, and that if you are sealing pavers less than a year old you should check with the paver manufacturer first. A trowelled or very smooth slab that does not readily absorb water may need acid etching or grinding before either product will bond. If you are not yet sure your slab needs a film at all, our batch guide on whether you should seal concrete works through that decision before you get to sheen.

6. Application and Recoating Are Identical

Because they share a base formula, the two sealers go down the same way. Foundation Armor specifies a 3/8 to 1/2 inch nap roller or a solvent-resistant commercial pump sprayer, two coats spaced 24 hours apart, and air and surface temperatures between 55 and 85°F. The surface has to be completely clean and dry, and if it was pressure washed the maker wants at least 24 hours of drying before sealing. Spot treatment may be needed for old or deep stains that pressure washing does not lift.

Timing is the instruction most DIYers miss. The maker says to apply only in the early evening, when air and surface temperatures are falling and the sun is off the surface, and not in the morning or middle of the day, to avoid bubbling and hazing. It also warns against early-morning application when dew is present. That evening-only advice is stricter than the generic seal-when-it-is-cool guidance you will find elsewhere, and it applies to both products.

On pavers with loose joint sand, the data sheets recommend spraying the first coat, because a roller can pick sand out of the joints and spread it across the face of the pavers. Neither product is a joint stabiliser; the maker states plainly that it will not harden or bond loose sand. If joint stability is the goal, that is a job for polymeric sand before sealing rather than for the sealer. Our wet-look paver sealer guide covers products that are designed to lock joints.

Recoating is where solvent-based acrylics shine. Foundation Armor calls both products self-priming and says that when it is time to reseal, a single coat on a clean, dry surface is enough. Because both are solvent-based acrylics, they are also compatible with each other, so you can switch sheen at the next recoat: AR500 over an AR350 base to add shine, or AR350 over AR500 to tone it down. Do a test patch first, since the final look depends on how much of the old film remains and how porous the slab is.

If the existing film is failing, peeling or badly built up, recoating will not fix it. The maker says cured sealer can be removed with its Armor CR100 stripper or by grinding, sandblasting or similar mechanical methods, and the AR500 data sheet specifically says to remove water-based acrylic or old, degrading solvent acrylic with CR100 before applying. White blush from trapped moisture is a separate problem with its own fix, covered in our guide to why concrete sealer turns white.

7. Which One to Buy: Our Recommendation by Surface

For most homeowners, the AR350 is the better default. It gives the same colour enhancement and the same protection claims as the AR500, it looks more natural on textured stamped patterns and broom-finished concrete, it hides wear and minor cosmetic flaws better, and it is the safer starting point anywhere people walk on wet concrete. That is why the low-gloss version is the one we covered in depth in our AR350 review and the one most readers searching for an Armor stamped concrete sealer should start with.

Choose the AR500 when the gloss is the point. A smooth stamped pattern with strong integral colour, a covered porch, a carport or a pole barn floor, or a feature area you want to look freshly poured and glassy are all good fits. Go in knowing that you will add non-slip on any walking surface, that worn traffic paths will show sooner, and that the maker's 1 to 3 year exterior life claim is the same as the AR350's, so you are not buying extra durability with the extra shine.

If you cannot decide, do what Foundation Armor itself suggests and test. Buy the 16-ounce sample of each, clean and dry a corner of the slab properly, and apply two thin coats of each side by side in the evening. Look at the result after a few days, in sun and in shade, wet and dry. The panel you still like after a week is your answer, and the cost of two samples is trivial next to sealing an entire patio in a sheen you end up disliking.

And if neither sheen appeals once you see it, that is useful information too. A penetrating silane or siloxane sealer protects against water and deicing salt without changing the appearance, lasts longer between applications and cannot peel. Our best stamped concrete sealer roundup ranks both film-forming and penetrating options, so you can compare these two against everything else before buying.