If you are considering buying a property, there are lots of things that you will need to consider. Number and size of bedrooms; whether you really like that avocado bathroom suite or not; presence of a good school; etc.
However, you probably won’t be looking at the plants in the property’s garden or even neighbouring properties gardens either, perhaps you should! Japanese knotweed is no respecter of boundaries.
So what happens if you buy a house (new or second hand), and suddenly in the spring lots of knotweed shoots start springing up through the garden. What are your legal rights?
The short answer is that you don’t have any legal redress. The slightly longer answer is IF you can prove that the seller knew about the Japanese knotweed (and knew that it was Japanese knotweed) and then took steps to conceal the weed’s presence (without doing anything else, such as landscaping the garden), than you have a slim possibility of recovering any loss in a court of law (but how would you prove this?). So no real difference between the answers, Caveat Emptor (let the buyer beware) is the let out.
What about the NHBC Home Buyers guarantee or your building insurance? Well basically the NHBC only covers structural damage, so if the knotweed is growing through the building you might stand a chance of making a successful claim; the most likely scenario is that the knotweed will grow around the building first. If you treat the knotweed, than structural damage probably won’t occur, BUT if you fail to treat the knotweed than any claim is likely to fail because you didn’t treat it when you could (Catch 22). All insurance policies (to my knowledge), specifically exclude claims for knotweed damage – read the small print of your existing policy!
So if you’re buying a property, it is worthwhile at least knowing what knotweed looks like. As a brief guide to where knotweed is commonly found, I would say that it is common throughout England, Wales, Scotland, Ireland and Europe generally and very common in South Wales, Greater Manchester, Greater London, Coventry, West Midlands, Sheffield, Liverpool and the Merseyside, the West Country, Norfolk, Essex, West Scotland – to name but a few! I recently moved and have already found knotweed in our Northamptonshire village in a dozen places already (I had thoroughly checked the gardens and immediately surrounding area and they were OK).
I’ll be covering mortgages and knotweed in my next blog. The usual question that we get is “I’m selling my house, and the buyer’s surveyor has found Knotweed, and they now can’t get a mortgage.” We’ll discuss this next week.
Please email Brian Taylor here with any specific questions that you want him to address through the blog or otherwise and he will try to answer them.






My neighbour has Japanese Knootweed in their garden and woods and it has now started to ingress into my garden. My neighbours refuse to do anything about this. What is my coarse of action and what are my legal rights. If I go legal how can I recover any monies I spend on legals.
Alan Batten
Alan, Thank you for your question. The law concerning Japanese knotweed is covered by the Wildlife & Countryside Act (1981). However this is of little help to you, as it only concerns plants growing in the wild. I will address this topic in my blog this week, as there is some case law, which may be useful to you and I have insufficient space here to cover it.