How to Stabilize Soil in Cold Climates With Perma-Zyme

Road stabilization in cold climates is challenging. From the shorter construction season to ferocious freeze-thaw cycles, finding a soil stabilizer that can withstand freezing temperatures for more than a few months—let alone multiple seasons—is difficult.

Let’s examine how four common soil stabilizers react to cold weather and how this affects your roads. Then, we’ll teach you how to stabilize soil with Perma-Zyme, the enzyme soil stabilizer that can last 10+ years in cold climates.

Road Stabilization for Cold Climates

Cold climates damage roads because freeze-thaw cycles cause soil to heave upward, collapse, and erode. Frost and ice push soil particles up, while trapping unfrozen water in the soil. When it thaws, more water moves through the soil, creating potholes, wash-outs, and other erosion problems.

Most road stabilizers are susceptible to cold, especially if temperatures suddenly drop after application. Even if you apply them in warm weather, they may fail after experiencing repeated freeze-thaw cycles. The more freeze-thaw cycles your region encounters, the more likely they are to damage infrastructure.¹

Let’s consider how four popular road stabilization products perform in cold climates.

Lime

Lime can be effective for cold-weather road stabilization because it produces heat. When mixed into cold soil, it warms the soil enough to melt frost up to three inches deep. It also works well in fine-grained and highly plastic soils. And if it gets too cold to cure right away? It will cure later when the right conditions occur.² (However, the uncured soil may shift before ideal conditions occur and need to be reworked.)

Using lime has some drawbacks:

Lime is expensive and usually unfeasible for unpaved roads.
It produces limited heat, so it’s ineffective in extreme cold.
A three-inch depth is insufficient for most road stabilization projects.
Lime may only last a couple seasons. Ten freeze-thaw cycles can weaken lime-treated roads, and most cold climates experience multiple freeze-thaw cycles each season.³
Just three freeze-thaw cycles can increase lime-treated clay soil’s permeability up to 20 times, making clay roads more susceptible to erosion.⁴

Cement and Asphalt

Most people pave with asphalt when temperatures are 55°F or above, as that’s when asphalt is easiest to work with. You should also be able to use cement soil stabilization when air temperatures are around 40°F. Like lime, cement produces heat that can help prevent it from freezing while it cures. So, if you’re applying them when the weather is already cold, cement soil stabilization is a better bet. Asphalt is more commonly applied during warmer months.

Some concrete workers say cement and asphalt become harder and stronger during cold weather because they cure more slowly. Unfortunately, science doesn’t support those claims. Here are the cons of cold-weather cement and asphalt road stabilization:

Cement and asphalt are both expensive.
They’re vulnerable to mixing and application errors.
Asphalt is more likely to fatigue at low temperatures.⁵
Compressive strength tests show that when cement cures at low temperatures, it’s weaker and more breakable than cement cured at normal temperatures.⁶ Some states have even banned using cement-stabilized material that cured at low temperatures.⁷
Cement that freezes while curing can lose up to 50% of its compressive strength.⁸
Cement and asphalt can become brittle and crack in cold weather, making paved roads collapse.
These materials are porous, so water can seep into them and cause more damage.

Chlorides

Chlorides are salt compounds popular for winter road maintenance because they act as de-icers. They melt ice by pulling moisture from it and lowering the freezing temperature of water to prevent it from refreezing. As a bonus, they have soil stabilization and dust suppression properties, so they can treat roads year-round.

So, are there disadvantages to chlorides? Let’s take a look:

Chlorides can pollute water and soil near roads.
Chlorides wash away quickly, so they need frequent reapplications.
Their tendency to wash away limits their soil stabilization capabilities and renders them less effective at combating freeze-thaw damage than other methods.
They make their way onto the undercarriages of vehicles, causing corrosion to the tune of nearly $4 billion per year in the trucking industry alone.⁹
While magnesium chloride and calcium chloride work at temperatures below 15°F, sodium chloride—the most common type of road salt—doesn’t.
Deicing with chlorides is costly, since you must apply it before each snow, so many counties and cities only deice a few roads. Before a 2016 snowstorm, Portland, Oregon, applied 10,000 gallons of magnesium chloride to 518 miles of public city roads—covering only about 25%.¹⁰^,¹¹

Using Perma-Zyme for Cold-Weather Road Stabilization

Perma-Zyme is an alternative to traditional soil stabilizers that tend to wear down in the cold. Its unique enzyme formula binds soil together into a hard, concrete-like surface that can stabilize roads for over 10 years in even the coldest of climates. So, let’s take a closer look at five reasons to try this powerful road stabilizer.

1. Perma-Zyme Works in All Climates

When we say all climates, we mean all. People have used Perma-Zyme everywhere, from tropical climates to continental and temperate ones. Some of our cold-weather customers hail from:

Utah
Alaska
Michigan
Eastern Europe
British Columbia

Perma-Zyme is effective in these climates because, during cold weather, its enzymes enter a dormant state. They essentially “freeze” in place, so as long as they cured to full strength after the initial application, they’ll remain at full strength even during their dormancy. This keeps treated roads hard and durable year-round. With lower risk of weather-related road damage, Perma-Zyme reduces the risk of winter accidents.

2. It’s Resilient From Freeze-Thaw Cycles

Perma-Zyme is ideal for frost heave prevention, as well as protecting against other freeze-thaw damage. Frost heaves occur when water under the soil’s surface freezes, causing the soil to swell. When the soil thaws, it—and everything on top of it—collapses. This makes both paved and unpaved road surfaces buckle, creating potholes and low-lying areas that become swampy. Worse, roads can become impassable.

Perma-Zyme’s hard, concrete-like surface is almost completely impervious to water, so your soil will stay much drier. With less moisture in the soil, it won’t experience the significant swelling and collapse of frost heaves. Once the soil thaws, the Perma-Zyme treated surface won’t absorb water. That means no more muddy, messy dirt roads in the spring! Your roads will stay passable year after year.

3. You Can Apply It in Cool Weather

You can apply Perma-Zyme in temperatures as low as 40°F (4.4°C). With this temperature range, you can continue stabilizing your roads well into November and as early as March in places like Michigan, helping extend your road construction season.

The soil takes 72 hours to cure sufficiently to support normal traffic and will continue hardening for the next four to six weeks. It’s imperative that daytime temperatures stay above 40°F for the full three-day curing period, as cooler temperatures can slow down the enzymes’ activity and prevent thorough curing.

4. Perma-Zyme Is Long-Lasting

One Perma-Zyme treatment lasts for years with little to no maintenance. Its lifespan varies by traffic and road type. One treatment can last:

Up to five years for heavy industrial haul roads
10+ years for county and local roads, driveways, etc.
20+ years for paved road subbase

So, you don’t have to worry about constant road stabilization or frost heave prevention; one Perma-Zyme treatment will hold up all season long and for many seasons beyond!

5. It’s Strong Enough to Stand Up to Snow Plows

During compressive strength tests, Perma-Zyme treated soil was up to 13 times stronger than untreated native soil. Technicians also tested the treated soil’s r-value to measure its resistance to vertically applied force, such as the force traffic exerts on a road’s surface. The r-values of Perma-Zyme treated soil samples clocked in from 90% to 95%. That’s stronger than Type II aggregate—and nearly as strong as steel! (Speaking of aggregate, you can embed a gravel topcoat in the Perma-Zyme treated surface for added traction on snowy days.)

Perma-Zyme can tolerate the weight of snow plows and salt trucks without sustaining serious damage. Of course, some minor wear-and-tear may occur—after all, an unpaved road is still an unpaved road—but it won’t develop serious potholes, washboarding, ruts, or gouges from plow blades like ordinary roads do.

How to Stabilize Roads in Cold Climates With Perma-Zyme

Road stabilization with Perma-Zyme is a straightforward process. Here’s how to do it:

Check your soil’s level of Perma-Zyme compatibility with our free soil evaluation and get custom recommendations to help make your application successful.

Plan your application. Consider road design and drainage, and schedule construction when temperatures will be above 40°F with no rain or snow for at least 72 hours.

Prepare the road. Clear large objects or debris piles from the road.

Rip up the soil with a motor grader, six inches deep for medium-traffic roads or 12 inches for heavy traffic.

Presoak the soil to approximately 80% of its optimum moisture content.

Apply Perma-Zyme, spraying it evenly on the road’s surface.

Mix in the Perma-Zyme. Using a grader, work the Perma-Zyme into the soil thoroughly to create a strong, long-lasting bond.

Compact the soil. Compaction is the key to a successful application. Keep the soil moist (but not saturated) and compact it thoroughly with a padfoot compactor, followed by a smooth wheel compactor. Now's the time to add that optional gravel topcoat if you want to.

Let the soil cure for three days. Ideally, the road should remain closed for the first 24 hours. If that’s not an option, allow only light traffic on the road (such as passenger vehicles) and reduce the speed limit for 72 hours.

Apply a pavement topcoat (optional). Treating your subbase with Perma-Zyme can reduce paving costs by up to 80%, making paving more affordable for many rural roads. Remember, follow the proper protocols for cold-weather paving if you’re doing a late-season application.

And there you have it. Applying Perma-Zyme is a simple, one-time process that lasts for years in even the coldest climates. Ready to give it a try? We’re here to help you create a safe, stable road with Perma-Zyme.