Blog>Expert Advice>What to do about drain root intrusion
Last updated: 11 October 2024
What to do about drain root intrusion
Are tree roots invading your pipes and causing drainage issues? Find out how to remove roots from your drains with this guide.
Drain root intrusion happens when tree or plant roots grow into your drainage system.
It's a surprisingly common problem that leads to anything from small clogs to full blockages. Eventually, leaks and structural damage are the reward.
If you don't deal with these invading roots quickly, your drainage system can suffer serious damage and require pricey repairs.
So, how do you deal with roots growing into your drain? Get answers to all your questions here.
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What is drain root intrusion?
Roots of nearby trees search for moisture or nutrients - unfortunately, these roots can grow into your drains and sewer pipes.
Once the roots infiltrate your pipes, they grow and grow over time.
The result is severe blockages that disrupt water flow to and from your home. In some instances, intrusive roots can even break your pipes.
Older clay or concrete pipes are particularly susceptible to drain root intrusion. Modern plastic pipes, like PVC, can also be affected by tree roots, but not to the same degree.
Root intrusion treatments
Depending on the severity of root intrusion and the type of drainage system, you can try serveral treatments.
A drainage expert can advise you on the best solution for your circumstances.
They might suggest;
1. Chemical removal for roots
Pouring chemical root killers down the drain can potentially kill tree roots.
Some options include;
Foaming root killers
Herbicide root killers
Copper sulphate root killers
A herbicide coats the pipes inside to kill the roots on contact.
But, root killers are not always a permanent solution, and they can harm affected plant life.
2. Drain snakes or augers
Another common approach to removing drain roots is using drain snakes/augers.
These flexible tools move through the pipes (you guessed it—like a snake!) to break up and remove the roots.
It's best to let a drainage specialist tackle any blockages due to tree roots. They will rotate these tools inside your drains to dismantle and dislodge the roots, without damaging your pipes.
3. Hydro jetting roots
When the above options aren't suitable, consider hydro jetting.
Hydro jetting uses high-pressure water as an aggressive way to clear blocked drains.
It will blast away almost anything to restore the full diameter of your pipes, including tree and shrub roots.
For longer-lasting results, combine hydro jetting with periodic maintenance.
4. Cutting roots out of sewer line
Mechanical cutting may be a better option if these root intrusion treatments don't work.
A drainage specialist can use a rotating blade or specialised cutting tool to cut away the roots in your drains.
Although an effective treatment, mechanically cutting roots is only as effective as the preventative steps to stop regrowth.
Because drain root intrusion can be serious, get help from a trusted drain repair.
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Stopping root regrowth
Things you can do to prevent further instances of root regrowth include;
Regularly check drains for signs of growing roots or blockages
Arrange regular CCTV drain surveys to check for roots or clogs
Apply growth inhibitors like root killers or slow-release chemicals
Choose pipe-lining as a long-term solution for free-flowing pipes
Perform semi-regular hydro jetting to remove tree roots before they take over
Plant new trees away from pipes and buildings
Choose non-invasive trees with less aggressive root systems
Remove nearby trees (if possible), especially if you have old clay pipes
Install physical root barriers to stop tree roots from invading pipes and sewers
FAQs
How do you fix a root intrusion in a sewer line?
You can try these steps when dealing with penetrating roots in your sewer line.
Ask a professional to inspect the extent of the damage to your drains with a CCTV drain survey
Try root intrusion treatments listed above, based on the nature and severity of the root intrusion
Repair any damaged pipes or drains; drain relining might suffice, but a replacement drainage system might also be required
A hassle-free option is drain lining, as it restores the structure without excavation.
Who is responsible for tree root damage to drains in the UK?
In the UK, homeowners are responsible for maintaining any drains within their property boundaries.
But, if the penetrating roots are from a tree on public land or neighbouring property, your local authority or neighbour may be responsible.
Contact your local authority to discuss clearing the tree roots they may be responsible for.
Does building insurance cover tree root damage to drains?
Whether your home insurance covers damage from tree roots growing in your pipes depends on your policy.
Sometimes, your insurance provider might cover drain root intrusion repair costs if there is serious structural damage.
The best thing to do is check your policy or speak to your insurance provider. They can confirm what's covered.
Is it illegal to build over a drain?
Although private drains are the responsibility of the homeowner/landowner, building over or near public sewers or drains is usually allowed.
But, you'll need to apply for a build-over agreement from your local authority if building;
Within 3 metres of a public sewer
Within 1 metre of a public lateral drain
You'll also need to ensure that the drain is left accessible for maintenance and that the building work doesn't lead to pipe damage.
Find out more about building regulations here, or check out more drainage advice.
How to tell if a drain pipe is broken underground?
We all know how far tree roots can reach.
So, the longer the roots have to spread in your drainage system, the more problems they will cause.
Although it's hard to know what's happening inside our pipes, there are some common telltale signs of roots growing in your drains.
Keeping an eye out for these common drainage warning signs;
Frequent recurring drain blockages
Foul odours from your drains or garden
Standing water or sinkholes near your foundations or in your garden (especially when it hasn't rained)
All of the above suggest blocked, broken or leaking pipes, the cause of which could be root-related.
If you notice any of these signs, immediately arrange a tree root inspection. A CCTV drain survey is one of the most efficient options.
A CCTV drain surveyor will use a specialised camera to enter the drainage system and inspect it for issues.
Drain root intrusion costs
The cost of removing roots from drains depends on the extent of the root intrusion and the removal method.
Here are some examples;
Basic drain repair costs are between£450 - £750
Drain patch repair costs are around £200 - £450
Replacement pipework can cost on average £635 per metre
CCTV drain surveys costs between £150 - £400
Learn more with our guides to drain repair costs and collapsed drain repair costs.
Chat with a drainage specialist for an accurate quote to get your drains root free.
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