SRW X-Treme™ Polymeric Sand – 50 lb Bag (Wide Joints up to 6")

Ships Same Day From our NJ warehouse

50 lb Bags 20 to 45 sq ft per bag

Rain Safe in 20 Min Fastest wide-joint setup

Real Humans (856) 418-4895

Why Pros Reach for X-Treme on Stone

Ordinary polymeric sand is engineered for tight paver joints and starts to fail as joints get wider: weak cures, washout, and haze baked onto stone where residue has nowhere to hide. X-Treme™ was engineered in the other direction, specifically for the wide, irregular joints of natural stone and wetcast.

• Strong, solid cure up to 6 inches. SRW's advanced polymer technology produces a stronger, more durable cure, which is exactly what wide joints demand. Long-lasting joints resist washout, weeds, and insect infestation with less maintenance.
• No haze. The polymers dry clear, so flagstone, bluestone, and wetcast come out clean with a haze-free finish.
• Rain safe in 20 minutes. The fastest wide-joint setup time on the market. An unexpected shower 20 minutes after activation does not mean starting over.

Coverage: How Many Bags Do You Need?

Each 50 lb bag of X-Treme™ typically covers 20 to 45 square feet. Wide-joint natural stone runs toward the low end of that range, tighter and shallower joints toward the high end.

Actual coverage depends on stone thickness, joint width, and joint depth, and irregular stone eats more sand than you think. For an exact bag count, use our free Polymeric Sand Calculator, or call or text us at (856) 418-4895 with your square footage and joint width.

Where X-Treme Works

X-Treme™ is recommended by SRW for joints from 1/4 inch up to 6 inches at intersecting points, with a minimum joint depth of 1-1/2 inches, in residential and commercial installations:

• Natural stone joints (flagstone, bluestone, irregular stone)
• Wetcast joints
• Walkways and patios
• Pool decks (not the copings)
• Pedestrian traffic areas

Where X-Treme Should NOT Be Used (Straight From the Manufacturer)

We would rather tell you this before you buy than argue about it after. Per SRW's technical data sheet, X-Treme™ is not recommended for concrete pavers, clay pavers, concrete overlays, or wet and heavily shaded areas, and should not be used on pool copings, submerged surfaces, or constantly wet surfaces. It is not a mortar substitute, so do not use it on paving stones set over concrete bedding, and do not sweep it over asphalt, since staining may occur. If your project is a standard paver patio, SRW Pavermate Z3™ is the right SRW sand for the job.

Not sure if your project qualifies? Call or text us at (856) 418-4895 before you order. We will give you a straight answer, even if the answer is that this is not the right product for your job.

Installation at a Glance

The full step by step guide is in the official TDS below. Here is the shape of the job:

1. Prep. Stone or wetcast must be level, stable, and completely dry (wait 24 hours after rain), with irrigation systems off until the sand has fully cured.
2. Fill. Gently tumble the bag, then sweep sand into joints to full depth. For natural stone, spread over the surface and sweep in without dragging sand long distances, which can separate the polymers. For wetcast, pour directly into the joints and keep sand off the surface.
3. Compact by hand. Use a rubber mallet along stone edges and a small blunt object in open joint areas. Top off low joints and compact again until nothing moves. No plate compactor on stone.
4. Set the height. Broom off remaining sand and set joint height with a leaf blower on idle. Finished joints should sit 1/8 inch below the top of the stone.
5. Activate. Working in sections up to 100 square feet, water each section for a total of 2 minutes: mist first, then a light shower repeated twice. Test with a screwdriver for at least 1 inch of moisture depth, then blow off excess water.
6. Cure. Joints are rain safe 20 minutes after activation. For best results install when no rain is forecast for 24 hours, and wait 28 days before cleaning or sealing.

Keep temperatures above 32°F throughout installation and curing, and always test in a small discrete area first.

Pick Your Color With Confidence

X-Treme™ is available in Tan and Granite. SRW notes in their own documentation that actual color varies by geographic location, and screens make it worse: every monitor shows color differently. On wide joints the sand is a big part of what your eye sees, so the stakes are higher than on a tight paver joint.

Not 100% sure which color matches your stone? Order our $10.99 X-Treme Color Sample Kit first. You get real 2 ounce samples of both colors, filled by us from the same factory sealed bags on this page, so you can compare them on your actual stone before buying full bags. Polymeric sand is permanent once cured. Ten dollars of certainty is cheap.

Quick Answers

How soon after installation is X-Treme rain safe?
20 minutes after joint activation, the fastest wide-joint setup on the market. A flexible joint at that stage means the reaction has occurred but the joint is not fully cured yet. For the best long term result, install when no rain is forecast for 24 hours and allow the full cure time.

Can I use X-Treme on my paver patio?
SRW does not recommend X-Treme for concrete or clay pavers, and we will not tell you otherwise just to sell a bag. For pavers, SRW Pavermate Z3™ is the right product. Call us and we will help you figure out which sand fits your surface.

Do I need a leaf blower?
Yes. A blower is required: on idle to set the joint height after sweeping, and again to blow off excess water after activation.

When can I seal my stone after sanding?
Wait 28 days after installation before cleaning and sealing.

Does X-Treme stop weeds and washout?
Properly installed and cured joints form a strong, solid bond that helps prevent washout, weed growth, and insect infestation, with less maintenance over time.

What if it is cold out?
Temperatures must stay above 32°F throughout installation and curing. If a freeze is coming, wait.

How should I store extra bags?
In original packaging, in a dry place away from UV. Outdoor storage requires an opaque, waterproof tarp, and opened material should be brought into a covered area.

Is there anything I should know about handling it?
Like all polymeric sands, X-Treme contains crystalline silica. Avoid breathing dust, wear eye protection during installation, and keep it out of reach of children. Full precautions are in the SDS below.

Official SRW Product Documentation

Documents are published by SRW Products. For the most current versions, visit SRWProducts.com.