Japanese Knotweed & Mortgage Applications | TP Knotweed Solutions

Japanese Knotweed & How It Can Affect Your Mortgage

Why could Japanese knotweed be dangerous for your property?

Buying a property can be a stressful experience, and your dream move can quickly become a nightmare if Japanese Knotweed is discovered on the property. Japanese Knotweed is the UK’s most invasive plant and can cause serious damage to properties if left unchecked. Growing up to seven metres high, knotweed forces itself through walls and tarmac and can block drains and ruin patios. Removing Japanese Knotweed can be an expensive and lengthy process, and if you’re buying a property affected by it the issue could last years. This is why mortgage lenders have mixed approach to how it handles cases of Japanese knotweed, as it can end up being very costly.

Can I get a mortgage on a property with Japanese knotweed?

The presence of Japanese knotweed will most likely affect the valuation of your property. In some cases, any sign of knotweed or other potentially invasive plant species could result in the lender declining the mortgage. Frustratingly, some lenders may refuse to lend on homes where knotweed is present several gardens away, or on public land, even if the house you’re interested in is unaffected. It isn’t impossible to get a mortgage on a property affected by Japanese Knotweed, but lenders will be cautious to do so.

Mortgage lenders’ position on Japanese Knotweed

Mortgage lenders often require evidence of a suitable treatment programme as a condition of lending if Japanese knotweed is present on or near to a property. Lenders may retain some of the mortgage until the buyer can prove they’ve successfully eradicated the knotweed. A 10 Year Insurance Backed Guarantee must also be in place upon completion.

What do Mortgage Lenders generally like to see:

Comprehensive Japanese knotweed survey detailing the full extent of the problem.

5 Year Herbicide Treatment Programme or Complete Excavation and off site licensed disposal

A 10 Year Insurance backed Guarantee upon completion

Have questions about assurance for mortgage lenders?

What is your mortgage lender saying?

Lenders will handle cases of Japanese knotweed differently according to their particular guidelines. Some individual lenders are willing to consider applications on a case-by-case basis, but you may need to commit to treat the knotweed or begin initial treatment before getting a mortgage confirmed. Here are the stances of some of the UK’s biggest lenders on Japanese knotweed mortgages.


Barclays demands an expert site assessment, and will not offer a mortgage until the knotweed has been treated.


Nationwide Building Society says: “If knotweed is prominent less than seven metres from the house we request a specialist report about eradication before deciding whether we can lend. Even if further away we require written confirmation from the borrower they are happy to proceed with a mortgage application despite presence of the plant.”


Santander expects professional knotweed treatment before lending homeowners money. It also expects you to keep money aside for future treatments in order to keep the garden clear.

Our Removal Guarantee

If your property is being purchased or sold, we offer our 10 Year Insurance Backed Guarantee (10 Year IBG Policy).

As soon as our team have successfully removed all traces of Japanese knotweed from your land we can provide you with this guarantee. This will ensure your property or land is protected for up to 10 years. We can provide this guarantee at an additional cost, detailed within our written quotation.

TP Knotweed Solutions are industry leaders and accredited specialists, helping to resolve issues with knotweed on a daily basis. We offer a range of treatment options for Japanese knotweed, from in-situ herbicide treatment to complete removal of the plant and disposal to a licensed landfill. The options that our surveyors recommend will vary depending on your particular circumstances. All of our treatment plans are tailor-made to suit each individual Japanese knotweed case.

Have questions about assurance for mortgage lenders?