Trees can enhance your property’s curb appeal and increase the value of your home.
However, they can also damage your driveway if their roots spread underneath the asphalt.
Our team at Betz Works has years of experience repairing driveways that have been impacted by growing tree roots.
In this guide, we’ll explore how tree roots can harm driveways and what you can do to fix the damage.
Key Takeaways
- Tree roots can spread underneath driveways, leading to cracks, heaves, and unevenness in the surface.
- To repair the damage, you can trim small roots, install a root barrier, and seal the driveway cracks.
- Severe driveway damage should be assessed and repaired by professionals such as Betz Works.
How Do Tree Roots Damage Driveways?
Contrary to popular belief, most tree roots spread laterally near the surface of the soil, not deep into the ground.
Over 90% of the roots of many tree species are located in the top 60 centimeters of soil. Roots can extend 1 to 1.5 feet for every inch of the trunk’s diameter.
Roots grow wherever they can find water, oxygen, and nutrients. If a tree is planted close enough to your driveway, the roots can make their way to the soil under the asphalt.
As the roots grow under the driveway, they can push against the surface. Small roots may extend through existing cracks, and larger roots can break through the asphalt.
Roots also absorb water from the surrounding soil, which causes the soil to compact.
Over time, the compacting of the soil can lead to your driveway sinking or buckling.
Signs of Tree Root Damage
Here are some of the most common signs of tree root damage to your driveway:
- Cracks: Roots growing under the surface of the driveway will force the asphalt upward, leading to cracks. You might see cracks that start small and expand over time, especially in the spring when roots experience the most growth.
- Bumps: As the soil around the roots shifts, you may notice bumps forming around the cracks.
- Uneven or lifting surface: Tree roots put upward pressure on the asphalt, and when the pressure becomes too strong, the entire surface can lift up.
- Sinking or buckling: Instead of lifting up, some driveways might sink down as the tree roots cause the surrounding soil to compact.
- Drainage issue: Because roots can cause bumps, lifting, and sinking, rainfall may pool in your driveway without properly running off.
How to Repair Your Driveway in 6 Steps
1. Clean the Area
Cleaning the surface of your driveway will help you assess the damage and fill and seal the cracks properly.
Use a wire brush and hose to remove dirt and debris from the asphalt. Allow the driveway to dry completely before you do any more work on it.
2. Remove Small Surface Roots
You can remove the small, shallow roots to help fix the damage to your driveway and prevent the damage from reoccurring.
Use an asphalt saw to cut away the portion of the pavement where you can see roots pushing through. Then, use hand pruners to trim the small roots.
Pro Tip: Avoid cutting larger roots, as it can make them susceptible to disease and rot. In severe cases, this could kill the tree and cause it to collapse.
3. Install a Root Barrier
Pruning the small roots provides a temporary fix for the problem, but roots will grow back over time.
To prevent the roots from overtaking your driveway again, you can install a root barrier.
You can choose between a physical and a chemical root barrier to keep roots away from your driveway.
Physical barriers are typically made of metal, fabric, fiberglass, or polyethylene.
They physically block roots from growing so that the growth is directed away from your driveway.
A chemical barrier is a fabric that contains a compound, most often trifluralin, that stunts root growth.
Like with a physical barrier, the roots will grow away from the area instead of through it.
While trifluralin is generally considered safe, some chemical barriers can be dangerous for humans and pets, and some may cause environmental damage.
Before buying a chemical barrier, research the safety of the product to make sure it’s acceptable to use on your property.
To install a root barrier, dig a trench between the tree and the driveway, and place the barrier vertically into the ground.
Check the product description to make sure the barrier is facing the correct direction.
4. Fill the Cracks
Once you’ve trimmed the shallow roots and installed the barrier, it’s time to fix up the damage to your driveway.
Start by routing the cracks in the asphalt to create a uniform channel to apply the sealant. Then, remove any dirt or debris from the cracks.
Heat the sealant in a melter, and use a hose and wand to apply the sealant. Make sure the sealant is fully cured before driving on the surface.
For small or temporary fixes, consider using cold mix asphalt. This sealant is easier and safer for the layperson to use, and it doesn’t require specialized equipment.
5. Resurface Uneven Slabs
If the damage to the asphalt is only cosmetic, you could resurface your driveway instead of pruning the tree roots and installing a root barrier.
Resurfacing won’t fix underlying structural issues, but it will improve the appearance of your driveway.
If you enjoy DIY projects and your driveway is fairly small, you could resurface your driveway by yourself.
However, most homeowners prefer to hire a professional to get the job done safely and efficiently.
6. Monitor for Regrowth
Roots can regrow underneath your driveway, especially if you don’t install a root barrier.
Watch for early signs of root damage, such as small cracks in the asphalt or bumps in the surface.
Be especially alert for signs of damage in the spring, which is when roots grow the fastest.
When to Call the Pros
Repairing minor driveway cracks and damage can be a DIY project, but most repair jobs are best handled by professionals.
You should reach out to professional pavers if your driveway has multiple large cracks, cracks that are continuing to grow, or if the surface is lifting or buckling.
A professional paving contractor like Betz Works can assess and correct the cause of the damage, reducing the chances of the problem reoccurring.
They also have specialized equipment that will deliver high-quality results.
Our team at Betz Works begins each job by conducting an inspection of the site and providing a free estimate.
Then, we repair the driveway by filling cracks, removing and patching potholes, or resurfacing the asphalt.
Concerned About Tree Root Damage? We’re Here to Help!
Betz Works offers driveway repair services to homeowners in Santa Cruz, Monterey, and Santa Clara Counties.
Whether you need a few small cracks filled or a brand new driveway installed, we’re happy to help.
Contact us today to learn more about our services.
FAQ
How can I prevent tree roots from damaging my driveway?
Installing a root barrier is one of the best ways to prevent roots from growing under your driveway.
If you want to plant trees on your property, plant them at least 10 feet away from the driveway’s edge.
Do tree roots always cause damage?
Tree roots don’t always damage asphalt and concrete surfaces. However, any tree that’s too close to your driveway has the potential to do damage.
What should I do if a city tree damages my driveway?
If a city tree damages your driveway, contact your local government as soon as possible. Take photos of the damage so the issue is documented.
While laws vary from city to city, the municipality is usually responsible for paying for the repairs.
You can always consult with an attorney who’s familiar with the laws in your area.
What type of trees are safest for driveways?
Trees with deep root systems are better near driveways than trees with lateral roots.
The following are some of the best trees to plant near a driveway:
- White oak
- Walnut
- Black gum
- Sassafras
- Hickory
- Pine