Japanese Knotweed Stopped My House Sale. Why Was It Not a Problem When I Bought?

Japanese knotweed may remain unnoticed for years and only become a serious problem when a homeowner tries to sell. A buyer’s surveyor identifies growth on the property or neighbouring land, the buyer’s mortgage lender asks for further evidence and the transaction suddenly stalls.

For the homeowner, the obvious question is: if the property was acceptable when I bought it, why is Japanese knotweed preventing me from selling it now?

Why can Japanese knotweed stop a house sale?

Japanese knotweed does not automatically make every property unsaleable or unmortgageable. The practical problem is that the buyer, surveyor and mortgage lender may each need satisfactory evidence about the location of the plant, the extent of any infestation and the arrangements for controlling or treating it.

A buyer’s lender may require some or all of the following:

• a specialist Japanese knotweed survey;
• a treatment or management plan;
• confirmation that the contractor is suitably qualified;
• evidence that the treatment has been paid for;
• a completion certificate;
• an insurance backed guarantee;
• confirmation that the guarantee can pass to a new owner; and
• approval from the lender’s valuer.

If these documents are missing, the difficulty may be greater than the physical presence of the plant itself. An informal promise to cut it down or treat it may not provide the evidence required by the buyer or mortgage lender.

Consumer concern also affects saleability. As discussed in Japanese Knotweed: Why Half of Buyers Would Walk Away, uncertainty about knotweed can cause buyers to renegotiate, delay exchange or abandon a purchase even where professional treatment may be available.

Why was the property accepted when I bought it?

This is often the most frustrating part for the present owner. They may have bought the property with a mortgage after searches, a valuation and perhaps a survey. Years later, another lender takes a different view and the proposed sale stalls.

There are several possible explanations.

The physical circumstances may have changed. Japanese knotweed may have spread, previous treatment may have failed or a treatment plan or guarantee may have expired. A buyer’s surveyor may also identify growth that was not visible or recorded during the earlier transaction.

The buyer may be using a different mortgage lender. Lenders do not necessarily take an identical approach to Japanese knotweed, adjoining land, specialist reports, treatment plans or guarantees.

There is also another important possibility: the original lender’s own requirements may have changed since the property was bought.

The lender’s current policy may not reproduce the requirements that applied when the property was bought. See our analysis of historical Japanese knotweed lender requirements.

What did your mortgage lender require at the time?

A current lender handbook cannot reliably answer a historical question. The relevant issue is what the particular lender required on the date of the original purchase.

The Lexsure Lender Archive Japanese knotweed page allows the historical position to be investigated using the original completion date and mortgage lender.

The archived lender record may show whether the lender expressly required:

• the presence or suspected presence of knotweed to be reported;
• knotweed on neighbouring land to be disclosed;
• a referral to the lender or its valuer;
• a specialist survey or assessment;
• a treatment or management plan;
• a completion certificate;
• a guarantee of a particular duration; or
• specific action before the mortgage could complete.

This matters because lender requirements have changed over time. Our earlier article, Are Lenders Putting Conveyancers in a Stranglehold over Knotweed Obligations?, recorded how lenders were already introducing detailed reporting, treatment and guarantee requirements in 2016.

The later article, Japanese Knotweed Mortgage: What Applied When You Bought?, explains why the original lender, completion date and wording then in force must be examined together.

Why today’s lender requirements are not enough

A requirement published today may be different from the requirement that applied when the homeowner originally bought the property. A lender may have introduced a reporting obligation, changed the acceptable treatment evidence or altered its approach to knotweed on neighbouring land.

The reverse is also possible. A lender may have relaxed or reorganised its requirements. That is why the present handbook should not be used to reconstruct what the conveyancer was expected to do years earlier.

The historical record provides a dated starting point. It can establish what the lender’s published Part 2 instructions said at the relevant time and whether those instructions expressly addressed Japanese knotweed.

The archive does not prove that somebody was negligent

A historical lender record is evidence of what the lender’s published instructions said. It does not, by itself, establish that the conveyancer, surveyor, seller or another party did something wrong.

The record needs to be considered alongside the original conveyancing papers, which may include:

• the seller’s property information form;
• the environmental search;
• the mortgage valuation;
• any survey commissioned by the buyer;
• enquiries raised by the conveyancer;
• the replies and supporting documents;
• any Japanese knotweed report or treatment plan;
• the lender’s instructions and any referral made to it; and
• the Report on Title or other advice provided before exchange.

The fact that a mortgage was granted does not necessarily mean that the buyer received appropriate advice about future saleability. Equally, the fact that a later buyer’s lender refuses to proceed does not automatically mean that the original conveyancing was defective.

The circumstances of the property, the available evidence and the requirements governing the two transactions may be different.

What if the knotweed is on neighbouring land?

Japanese knotweed does not have to originate within the property being sold before it creates a transaction problem. Growth on adjoining land may concern a buyer’s surveyor or lender, particularly where it has crossed the boundary or the neighbouring owner has no satisfactory treatment arrangements.

This can leave the seller dependent upon somebody else taking appropriate action. Treatment within the seller’s garden may not resolve the underlying problem if the source remains untreated on the other side of the boundary.

A professional assessment may therefore need to identify:

• where the knotweed originated;
• whether it has crossed the boundary;
• how close it is to buildings, structures and usable areas;
• which land is covered by the treatment plan;
• who is responsible for carrying out and funding treatment;
• whether access to neighbouring land is required; and
• whether the documentation and guarantee will satisfy the proposed lender.

Historic lender requirements concerning neighbouring land are particularly relevant because some lenders have used distance based tests, while others have placed greater emphasis on the valuer’s assessment, the effect on the property and the available treatment evidence.

What should the homeowner retrieve?

If Japanese knotweed is delaying a sale, the immediate priority may be a reliable specialist assessment and an understanding of the proposed buyer’s lender requirements. However, the homeowner should also retrieve the records from the original purchase.

Useful documents may include:

• the original TA6 property information form;
• the purchase contract and replies to enquiries;
• the environmental search;
• the mortgage valuation and any private survey;
• the conveyancer’s Report on Title;
• correspondence about the garden or neighbouring land;
• historic photographs or sales particulars;
• any previous treatment records;
• the treatment plan and guarantee; and
• the identity of the mortgage lender and the completion date.

These documents may help establish whether the Japanese knotweed was known or suspected, whether it was reported to the lender and what the homeowner was told about treatment, guarantees and future saleability.

Start with what happened when you bought

Resolving the present sale problem and investigating the original purchase are separate but connected exercises.

For the present transaction, the homeowner needs to establish the current condition of the property, the available treatment evidence and what the buyer’s lender requires now.

For the historical investigation, the important questions are different:

• Was Japanese knotweed present or suspected when the property was bought?
• What did the seller disclose?
• What did the surveyor or valuer report?
• What did the mortgage lender require at that time?
• Was the matter reported to the lender?
• What treatment or guarantee documents were available?
• What advice did the conveyancer provide about future saleability?

The answers will not necessarily establish that anybody was at fault. They may, however, explain why a problem that appears new during the sale has its origins in the earlier purchase.

This article provides general information only. It is not legal, surveying, valuation, mortgage, treatment or insurance advice. The circumstances and documents relating to an individual property should be considered by appropriately qualified advisers.