Japanese knotweed rarely brings down a house. It brings down sales, mortgage offers and sometimes a seller’s defence in court.
In 2023, a buyer clearing the garden of his new £700,000 home in south-west London found knotweed growing behind a bush near the shed. The seller had ticked “no” on the TA6, and the bill that followed came to roughly £200,000. The plant hasn’t changed much since then, but the form has, so here is where knotweed stands for conveyancers in 2026.
What is Japanese knotweed, and is it illegal to have it?
Japanese knotweed is an invasive plant that spreads underground through rhizomes, and even small fragments can regrow. Left unmanaged, it can push through paving, crack garden walls and get into drains and outbuildings. It is far less likely to threaten the structure of a sound house, although buyers and lenders don’t always find that reassuring.
Having it isn’t illegal, and there’s no duty to remove it from your own land. The law applies in three other places. It is an offence under section 14 of the Wildlife and Countryside Act 1981 to plant it or otherwise cause it to grow in the wild. Knotweed and soil containing it count as controlled waste, so it can’t go in the green bin (or a skip). And councils can serve a community protection notice on an owner who lets it spread and does nothing about it.
What does the TA6 ask about it now?
Since 30 March 2026, firms accredited under the Law Society’s Conveyancing Quality Scheme have had to use the sixth edition of the TA6 for every new instruction. The fourth and fifth editions have been withdrawn, although matters already running on an older form can carry on with it.
Knotweed sits in section 8, Environmental matters. Question 8.6 asks whether the property is affected, and 8.7 asks about surveys and management plans. The Law Society’s explanatory notes say a property is usually treated as at risk if knotweed is growing on it or within three metres of its boundary. They also accept that sellers can’t easily be certain, because rhizome can sit in the soil with nothing showing above ground. That’s why many sellers answer “not known”.
Is “not known” a safe answer?
If it’s true, yes. An honest “not known” passes the job of investigating to the buyer, who can commission a specialist survey if they want certainty.
It isn’t a hiding place, though. A seller with a treatment invoice in a drawer doesn’t “not know”, and the notes are clear that sellers must answer from what they know and update their answers if anything changes before exchange. That applies to executors and attorneys too, even if they’ve never set foot in the garden.
The riskier box is “no”, because it is a positive statement that the plant isn’t there. In the 2023 case, expert evidence showed the knotweed by the shed had once stood around two metres tall and had been treated with herbicide during the seller’s ownership. The court didn’t accept that he believed his answer, and he was ordered to pay around £32,000 in damages plus up to £95,000 of the buyer’s legal costs.
Whatever happened to the seven-metre rule?
RICS dug it up in 2022, and unlike the plant, it hasn’t grown back. The RICS standard Japanese knotweed and residential property, in force since 23 March 2022, replaced the old rule of thumb that any knotweed within seven metres of a house was a problem.
Valuers now use a decision tree that places an infestation in one of four management categories, A to D, based on what it is actually doing: whether it’s affecting a structure, restricting use of the garden or simply growing nearby. Lenders generally only expect a retention in the more serious categories, and knotweed on a neighbour’s land within three metres of the boundary won’t usually trigger one by itself. Individual lenders can still set their own criteria, so it’s worth checking.
What if it crosses the boundary?
Then it becomes a nuisance question. In Network Rail v Williams [2018] EWCA Civ 1514, the Court of Appeal held that rhizomes encroaching onto a neighbour’s land can be an actionable nuisance before any physical damage is done, where the landowner knows (or ought to know) about the risk and doesn’t act reasonably.
The Supreme Court narrowed that in Davies v Bridgend County Borough Council [2024] UKSC 15. Knotweed had spread from council land into Mr Davies’s garden long before the council was in breach of any duty, and he couldn’t recover the loss in value that remained after treatment, because the breach hadn’t caused it. Historic spread is now a much harder claim to win. Knotweed heading over the fence today is a different matter.
What should a buyer ask for?
Paperwork. Where knotweed is present or has been treated, the buyer’s conveyancer should expect to see:
- a survey by a contractor accredited by the Property Care Association or the Invasive Non-Native Specialists Association
- a written management plan, usually running over several years
- an insurance-backed guarantee, typically for ten years, with confirmation that it transfers to the buyer
- records of the treatment carried out so far
The aim these days is management rather than eradication. A documented, guaranteed infestation is something a lender can work with. An undocumented one is a guess. An environmental search can also help show whether knotweed has been recorded nearby. [CHECK: confirm which OneSearch reports include knotweed data and link the specific product]
The knotweed behind that shed in south-west London cost its seller about £200,000, and hardly any of it went on digging. Almost all of it came from one tick in the wrong box.
So treat question 8.6 as the start of a conversation. A “yes” should arrive with a plan and a guarantee, a “not known” is an invitation to survey, and a “no” deserves a polite question about what it’s based on.
The residential property market has experienced a number of extreme stressors over the past 18 months: the cost-of-living crisis, rising inflation, rising interest rates, and the fall-out from last September’s mini-budget … not to mention the economic effects of the war in Ukraine.
No wonder overall market activity is down and transactions in 2023 are running at around 85% of the pre-Covid average (2015–2019). All this considered, you might think that every area of the market would be suffering. But there’s one market segment that’s showing remarkable resilience:
The non-lender buying sector, aka cash buyers.
In this blog post, we’ll look at the reasons behind that market resilience. But also, what are the potential risks for non-mortgage purchasers? And how can you help your cash-buyer clients make more confident investments, without sacrificing the strength of their negotiating position?
Cash purchases on the rise
According to statistics recorded by Savills, cash buyers accounted for nearly 8 out of 20 transactions (38.5%) in January 2023. By contrast, mortgaged home movers accounted for just over 5 out of 20 transactions (25.3%).
Since then, cash buyers’ share of the market has continued to grow. In an upcoming OneSearch webinar featuring Savills Director of Residential Research, Emily Williams, it points to data showing cash buyers comprised about 46% of all transactions in April 2023 – up from around 34% in late 2022.
The proportion of cash buyers is even higher in prime markets. In those areas, buyers tend to be less dependent on mortgage finance. For instance, this year in prime central London as many as 14 out of 20 buyers (71%) have purchased using cash only. That’s up from around 12 out of 20 buyers (60%) in 2022.
What factors are contributing to this resilience?
Cash buyers have, in fact, represented the largest market segment since 2011.
One reason for their apparent recent growth is down to the surge in lender-backed purchases post lockdown. Increased activity from mortgaged home movers saw cash buyers’ market share squeezed between 2020 and 2022.
Since March 2021, we’ve seen the proportion of mortgaged-backed purchases drop from 1 in 3 transactions to around 1 in 4. And while the market turmoil in the wake of the mini-budget made the headlines in October 2022, a noticeable falling-off in transactions has been evident since the stamp duty holiday came to an end in September 2021.
In large part, the dampening effect in the market stems from the cost of borrowing going up. That continues to be the major constraint on first-time buyers and mortgage-backed home movers.
But part of cash buyers’ market strength is also down to their comparative ability to move fast to completion. This can make them an attractive proposition to many sellers. Indeed, those with access to readily available funds can often negotiate a reduced sale price on the basis of a time-limited offer.
Yet a determination to move fast can see cash buyers take on risks that mortgage lenders would not.
To search or not to search?
It’s imperative to understand that searches play a vital role in a property transaction and whatever the circumstances a full range of searches as advised by a conveyancer is always the best way to get all the property information required to make an informed decision. However, some cash purchases are negotiated by buyer and seller and the timescales of search delivery can fall out of these agreed parameters, so some form alternative safeguard maybe required to enable the purchase to proceed.
Bypassing the searches altogether however, is ill-advised. Property searches typically only cost a little extra; the possibility of local authority delays mean that delays could push completion, back several weeks, which is why your cash buyer clients may want to skip this part of the conveyancing process – particularly if they have negotiated a sale using a timescale caveat (e.g., exchange in 31 days).
Fast forward a couple of years, however, to when your client is looking to sell: a more prudent buyer’s searches could uncover defects that were there to be discovered. Defects such as:
- Unauthorised building works
- The property’s location on a floodplain
- The lack of connection to a sewerage network
- Planned changes to traffic schemes
- Proposals for a nearby railway
- Previously rejected planning permission applications
- And many more.
These types of defects can significantly affect the resale value of a property. Not only might your client be unable to achieve the profit they had expected to make, but they might struggle to persuade other buyers and their lenders that their property is worth anywhere near what they paid for it.
Buyer beware
Why might a vendor be keen on a quick sale? Why might they be happy to accept a low offer? And why might they be marketing their property as for ‘cash buyers only’?
These are questions your cash buyer clients should be asking themselves.
It may be that the seller simply wants a fast and uncomplicated sale. Perhaps they need the proceeds quickly and don’t want to risk a sale falling through. So they’re prepared to accept a lower price to guarantee a speedy transaction.
Those are the good scenarios. But it could be they’re trying to rush through a sale so that known defects aren’t looked at properly. And because of the rundown condition of the property, perhaps they suspect that a mortgage provider won’t lend funds to a would-be buyer.
As corner-cutting goes, not undertaking searches can be particularly dangerous. Which is why mortgage lenders would never take the same risk. And why, at OneSearch, we believe a full suite of conveyancing searches remains the best way to gain a true picture of a property and its history.
But now there’s a new way for your clients to secure a level of protection, without jeopardising a speedy transaction or risking a drop in the property’s onward sale value.
Introducing Cash Buyer Express
Created for an area of the residential property market where speed is paramount, Cash Buyer Express from OneSearch has been designed with time-sensitive purchases in mind.
It’s the perfect solution for those cash buyers who don’t want to put transactions at risk but who want to be better informed and suitably protected. The ideal tool for those who don’t want to risk waiting 6–7 weeks for searches to come back, but who want to feel more confident in making what is, after all, a significant financial investment.
How does it work?
Peace of mind… at pace
OneSearch is the only company to hold a national database of most of the available local authority data on every property in England and Wales.
Cash Buyer Express provides up to 70% of the information you would normally get from local authorities. But your clients can expect results in as little as 24 hours, so there’s no hanging around.
In practical terms, a sale will go through just as fast with or without Cash Buyer Express. The difference is your clients will be better informed. More importantly, they will have the security of an insurance policy covering a reduction in the property’s resale value from unidentified defects.
Protection… on purchase
Your clients are protected by a £1 million No-Search Insurance policy with Aviva. This is tailor-made for non-mortgage transactions and provides cover for:
- A search of the local land charges register on form LLC1
- A search of CON29R and/or CON290 records
- A search of water and drainage records on CON29DW
- A search of the coal authority’s records on form CON29M
- An environmental risk assessment
- A full chancel repair liability search
The policy will compensate your clients for the difference between the price they pay for a property and any subsequent reduction in value caused by unidentified issues – for example, the existence of a public right of way – that a full local authority search would have revealed.
In a nutshell, Cash Buyer Express gives cash buyers clarity, confidence, and complete peace of mind – without delay.
Please be advised of the following price updates for Official CON29DW products, effective from 1st May 2022:
| Residential | Price Increase |
| CON29DW Geodesys (Anglian Water) | + £2.50 |
| CON29DW Northumbrian Water | + £2.50 |
| CON29DW Safemove (Yorkshire Water) | + £2.50 |
| CON29DW Severn Trent Water | + £2.50 |
| CON29DW South West Water | + £2.50 |
| CON29DW Southern Water | + £2.50 |
| CON29DW Thames Water | + £2.50 |
| CON29DW United Utilities | + £2.50 |
| CON29DW Welsh Water | + £2.50 |
| CON29DW Wessex Water | + £2.50 |
| Commercial | Price Increase |
| Geodesys (Anglian Water) – Commercial | + £5.00 |
| Northumbrian Water – Commercial | + £5.00 |
| South West Water – Commercial | + £5.00 |
| Southern Water – Commercial | + £5.00 |
| Thames Water – Commercial | + £5.00 |
| United Utilities – Commercial | + £5.00 |
| Wessex Water – Commercial | + £5.00 |
| Commercial Extra/ Plus | Price Increase |
| Severn Trent – Commercial Extra | + £18.00 |
| Safemove (Yorkshire Water) – Commercial Plus | + £9.00 |
Please note: this price increase only applies to Official CON29DW searches. The OneSearch DW will remain at its current cost.
Our Drainage and Water search is a key report in residential transactions, supporting your due diligence. The OneSearch DW clearly identifies the connection status of the Mains Water, Foul Sewer and Surface Water Sewer of your property.
To view our product card, click here. You can also view our current sample report here.
If your bundles include any Official CON29DW products, your account manager will be in touch. If you have any questions or comments, please email intro@onesearchdirect.co.uk or get in touch with us on 0800 052 0117 and we will be more than happy to assist you.
Please be advised of the following price and product updates from FCI, effective from 3rd March 2022:
| Residential | ||
| Old Product Name | New Product Name | New Cost |
| FCI Premium Residential (<0.25Ha) | FCI Premium Residential (<1Ha) | £64.20 |
| FCI Premium Residential (>0.25Ha-5Ha) | FCI Premium Residential (>1Ha-5Ha) | £115.80 |
| FCI Standard Residential (<0.25Ha) | FCI Standard Residential (<1Ha) | £60.00 |
| FCI Standard Residential (>0.25Ha-5Ha) | FCI Standard Residential (>1Ha-5Ha) | £114.00 |
| FCI Essential Residential (<0.25Ha) | FCI Essential Residential (<1Ha) | £53.40 |
| FCI Essential Residential (>0.25Ha-5Ha) | FCI Essential Residential (>1Ha-5Ha) | £75.60 |
| FCI Flood Residential (<0.25 Ha) | FCI Flood Residential (<1 Ha) | £23.40 |
| FCI Flood Residential (>0.25Ha-5Ha) | FCI Flood Residential (>1Ha-5Ha) | £46.80 |
| Product Name | New Cost | |
| FCI Energy Residential (<10Ha) | £20.40 | |
| FCI Premium Plus Planning | £83.40 | |
| FCI Planning | £35.70 | |
| FCI Premium Plus CON29M | £102.00 | |
| FCI Con29M | £42.00 | |
| FCI Flood Appraisal – Residential (Up to 0.25Ha) | £234.00 | |
| Product Name | Cost | |
| FCI Ground Stability Residential (<1Ha) | £20.40 | |
| FCI Ground Stability Residential >1Ha – <5 Ha | £27.30 | |
| FCI Ground Stability Residential >5Ha – <150 Ha | £68.40 | |
| FCI Premium Residential >5Ha – <150 Ha | £198.00 | |
| FCI Standard Residential >5Ha – <150 Ha | £174.00 | |
| FCI Essential Residential >5Ha – <150 Ha | £126.00 | |
| FCI Flood Residential >5Ha – <150 Ha | £100.20 | |
| FCI Enviro Appraisal – Residential (Up to 0.25Ha) | £294.00 | |
| Commercial | ||
| Product Name | New Cost | |
| FCI Retail <0.25 | £118.80 | |
| FCI Commercial <15Ha | £222.00 | |
| FCI Commercial >15Ha – <50 Ha | £372.00 | |
| FCI Commercial >50Ha – <150 Ha | £510.00 | |
| FCI Energy Commercial (<30ha) | £40.80 | |
| Old Product Name | New Product Name | New Cost |
| FCI Flood Commercial (<0.25Ha) | FCI Flood Commercial <15Ha | £75.00 |
| FCI Flood Commercial (>0.25Ha-5Ha) | FCI Flood Commercial >15Ha – <50 Ha | £115.80 |
| FCI Flood Appraisal – Commercial (Up to 5Ha) | FCI Flood Appraisal – Commercial (<2Ha) | £360.00 |
| Product Name | New Cost | |
| FCI Flood Commercial >50Ha – <150 Ha | £170.40 | |
| FCI Enviro Appraisal – Commercial (Up to 2Ha) | £540.00 | |
| Chancel Liability | ||
| Product Name | New Cost | |
| ChancelCheck | £27.60 | |
| ChancelCheck Premium | £103.20 | |
| Title Checker | £27.60 | |
| Title Check and Chancel Check | £46.80 |
If your bundles include any FCI products, your account manager will be in touch. If you have any questions or comments, please email intro@onesearchdirect.co.uk or get in touch with us on 0800 052 0117 and we will be more than happy to assist you.
As part of the Coal Authority’s pricing review, the prices for their mining reports will be increasing.
Please be advised of the new prices, effective from 1st November 2021:
| Residential | |
| Product | New Cost |
| Coal Report – Residential (Coal Authority) | £51.09 |
| Coal Authority Claims Report (50m Buffer) | £25.14 |
| Coal Authority Subsidence Claims History | £210.35 |
| Interpretive Coal Report | £154.81 |
| Residential Enviro All In One (On Coal Field) | £135.58 |
| Residential Enviro All In One (Off Coal Field) | £92.90 |
| Ground Stability Report – Residential | £106.44 |
| Commercial | |
| Product | New Cost |
| Coal Report – Commercial (Coal Authority) | £117.43 |
| Commercial Enviro All In One (On Coal Field) | £390.98 |
| Commercial Enviro All In One (Off Coal Field) | £244.01 |
| Ground Stability Report – Commercial | £181.39 |
If your bundles include any Coal Authority products, your account manager will be in touch. If you have any questions or comments, please email intro@onesearchdirect.co.uk or get in touch with us on 0800 052 0117 and we will be more than happy to assist you.
Join OneSearch and CLS Property Insight on Tuesday 12th October for a free webinar detailing Defective Lease Issues in Conveyancing.
This hour long session will help solicitors navigate the complexities of Defective Lease issues and the insurance solutions that help property transactions progress.
Including:
• Claims examples, case studies and likely scenarios
• What insurance policies typically cover
• What information is required to arrange insurance
The webinar will start at 11am, and you can register to attend at this link.
If you cannot make this date, and would like to receive a webinar recording, please click here.