Japanese knotweed mortgage (A 3 point guide)

In this brief blog, we will discuss Japanese knotweed mortgages, how to get a Japanese knotweed mortgage and the challenges you may face.

Can you get a mortgage if you have Japanese knotweed?

Yes, you can get a mortgage if you have Japanese knotweed but it really depends on the extent of Japanese knotweed in the property. Japanese knotweed can grow up to 1 foot per week during the summer months and they can grow inwards and damage the pipes and foundations of a home.

To get a Japanese knotweed mortgage you will need to assure the mortgage lender that the Japanese knotweed is under control. You can first treat the Japanese knotweed mortgage by employing a professional specialist. You should then look to obtain a GPI Japanese knotweed warranty for 10 years. This should improve the amount of Japanese knotweed mortgage lenders willing to lend to you.

When choosing a specialist Japanese knotweed provider to help you prepare for the Japanese knotweed mortgage you will want to find a provider whois PCA regulated. This means to get approved they have to adhere to the strict guidelines of the PCA. The PCA is a government-approved trade body for “the damp, waterproofing, wood preservation and invasive weeds industries”

Some Japanese knotweed mortgage lenders will have detailed criteria on what they expect to see in properties affected by Japanese knotweed.

If you don’t create a detailed plan for the Japanese knotweed then you will find that many Japanese knotweed mortgage lenders may be unwilling to lend to you.

Most Japanese knotweed mortgage lenders will expect you to have conducted a Japanese knotweed survey and then created a Japanese knotweed management plan which will report on what was found, elaborate on any Japanese knotweed issues and present a solution that will allow you to be able to get a Japanese knotweed mortgage.

Whether you should buy a house with Japanese knotweed will depend on if you can get a Japanese knotweed mortgage and if the Japanese knotweed is manageable.

If Japanese knotweed is found within 7 meteres of your home then it is classed as being affected by Japanese knotweed. Some mortgage lenders will even consider Japanese knotweed which was found at more than 7 metres to your property if they deem it close enough.

If Japanese knotweed is recorded on a property survey, the Royal Institute of Chartered Surveyors (RICS) has 4 risk categories:

“ Japanese knotweed is within 7 metres of a habitable space, conservatory and/or garage, either within the boundaries of this property or in a neighbouring property or space;


Japanese knotweed is causing serious damage to outbuildings, associated structures, drains, paths, boundary walls and fences and so on.

Further investigations by an appropriately qualified and/or experienced person are required ”

“Although Japanese knotweed is present within the boundaries of the property, it is more than 7 metres from a habitable space, conservatory, and/or garage. If there is damage to outbuildings, associated structures, paths and boundary walls and fences, it is minor. Further investigations by an appropriately qualified and/or experienced person are required.

Further investigations by an appropriately qualified and/or experienced person are required “

“Japanese knotweed was not seen within the boundaries of this property, but it was seen on a neighbouring property or land. Here, it was within 7 metres of the boundary, but more than 7 metres away from habitable spaces, conservatory and/or garage of the subject property. “

“ Japanese knotweed was not seen on this property, but it can be seen on a neighbouring property or land where it was more than 7 metres away from the boundary.“

As you can probably tell the Risk category 4 is the most severe category of the Japanese knotweed whilst risk category 1 is the least severe.

As mentioned prior, different mortgage lenders will have different criteria for Japanese knotweed.

Most Japanese knotweed mortgage lenders will want to see that the prospective owner has the capital to undertake any work needed and has a suitable Japanese knotweed guarantee lasting for at least 5 years linked with any remedial work which has been carried out.

Most Japanese knotweed mortgage lenders will have one of the below as part of their mortgage lending criteria:

“A fully funded 10-year Knotweed Management Plan (KMP) in place for the herbicide treatment of Japanese knotweed

A fully funded 10-year Knotweed Management Plan (KMP) with the benefit of an Insurance Backed Guarantee

Provision of ‘third party fund protection’ if the remedial work continues past the point of sale

No lending where major structural damage has occurred, otherwise it considers each case on its merits”

Japanese knotweed could affect house prices due to the belief that it can destroy the foundation of a house, pipes underneath the house or affect the structure of the house and make it unsafe.

In truth, Japanese knotweed may not be as bad as the media hypes it up to be. It certainly will cost you a lot of money to get rid of and this is where it mostly affects house prices.

This is one of the main reasons why getting a Japanese knotweed mortgage is hard.

Yes, Japanese knotweed can damage foundations but this is very rare. If you are worried that Japanese knotweed has destroyed or damaged your foundation then you should carry out a RICS survey to see if you are right.

If you are considering getting a Japanese knotweed mortgage then you may want to consider a survey as a priority as it will reassure the mortgage lender.

Use a Government scheme

Government schemes help you reduce the amount of mortgage deposit you may need to put down, reduce the price of the property or create a structure that increases your mortgage affordability much sooner than it would have been.

Some of these include first-time buyer government schemes whilst others in this list are accessible to you even if you are not a first-time buyer.

Government schemes are not available to you if you are getting a buy to let mortgage.

The Government schemes include:

  • Lifetime ISA– gives you a government bonus of £1,000 if you save a maximum £4,000 a year.
  • Help to buy ISA– gives a maximum bonus us £3,000 if you save the maximum allowed of £12,000. Before you get either you should consider which is better. Lifetime ISA vs Help to buy ISA.
  • Help to buy equity loan– gives you up to 40% as a 5-year interest-free equity loan. You begin to pay interest at 1.75 % after the fifth year and 1% plus RPI for every year thereafter.
  • Shared ownership– You can buy between 25% to 75% of the property initially with a shared ownership mortgage and then buy more using a staircasing mortgage.
  • Armed forces help to buy– similar to the help to buy equity loan but specific for the armed forces personnel giving them an increased chance of acceptance.
  • Rent to buy– This is the right to buy scheme on which this guide is currently discussing. A different marketing name is just used. Watch out for this when shopping to avoid missing out on eligible properties due to confusion.
  • Right to buy– allows you to buy your home at a discount price.
  • Preserved right to buy– same as above.
  • Right to acquire– similar to the above.

Depending on where you live, you may also be able to take advantage of home buying schemes provided by your local council. Example: In Norwich, the local councils provide the Norwich home options scheme.

Use a mortgage broker for your mortgage in principle

You may want to use an independent mortgage broker to help you get a mortgage on your new home.

Mortgage brokers are important as they can access mortgage products from across the whole of the market in some cases.

This could be over 11,000 mortgage products. This may have some advantages rather than going directly to a mortgage lender.

A mortgage broker will look to understand your financial circumstances and then provide recommendations on which mortgage products may be suitable for you based on your mortgage affordability.

After giving you these mortgage recommendations, most mortgage brokers will seek your consent to apply for a mortgage in principle

This will allow you to shop for your home as more estate agents and sellers may take you seriously and it will also give you confidence that your mortgage is indeed a possibility before you make a full mortgage application. 

Once you have found a home you want to buy and are satisfied with the mortgage offer for your mortgage then the mortgage broker will then look to get you a mortgage offer.

This will come with a key facts illustration document that details the features of your mortgage including how much you will pay per month.

It will also contain information on if there are any limits such as early repayment fees, or annual overpayment limits.

If you are happy with everything you can then go on to secure your mortgage with the help of a conveyancer.

Your conveyancer will manage the legal searches on the property to ensure there aren’t any issues with it.

They will oversee the sales agreement to ensure it is in your best interest, they will manage the transfer of mortgage funds, exchange contracts with the seller or their conveyancer, and set a completion date with the seller or their conveyancer.

This will then bring an end to the conveyancing process, at which point you will receive the keys to the house and move in.

If you need financial advice and you live in the UK then you could contact the Money Advice service over the phone or via chat for impartial advice.

You can also contact the debt charity “Step Change” if you are in debt and need help.