The most recent hot topic seems to be Japanese Knotweed. Whilst this is a very real problem, it has possibly been blown out of proportion by the media. There are frequent horror stories in the newspaper about incidents where the weed has grown through solid concrete and treatment has involved the removal of several feet of soil etc.

‘Storm in a teacup?’

Every now and then there is a new ‘hot potato’ in the world of buying and selling houses. Around 5 years ago, the potential of a Chancel Tax Liability was potentially being blown out of all proportion by the conveyancing sector, with sales falling through due to a risk that under ancient law, the new owners of a house could be asked to rebuild the tower on the parish Church. Interestingly, that ‘storm in a teacup’ seems to have blown over, but then others come along. Failed environmental searches, potential for Radon gas, missing FENSA certificates for double glazed windows….the list goes on. For now, Japanese Knotweed has the spotlight.

What is Japanese Knotweed?

Interestingly, Japanese Knotweed was brought into the UK in the 1800’s as an ornamental plant. It has lush green leaves, bamboo like stems and attractive white flowers in the autumn. It can grow at up to 10cm per day, so can soon take over if allowed to grow out of control.

Perhaps the greatest problem in the UK is that the plant is particularly well suited to the climate and there are few natural enemies for the plant in our eco-system.

How serious is it?

Japanese Knotweed, if left untreated, can be a pretty serious issue. It can grow through cracks in brick walls, come up through floors and once it has got a proper hold, can cause structural damage. Some surveyors have reported seeing it growing out of electrical sockets on the walls. Contrary to its reputation, it does not usually grow through solid masonry or concrete, but apparently will on occasions shoot up through cracks in concrete slabs etc.

How is it treated?

As this is a relatively new issue, the treatment methods are still under development. In some earlier cases, it was deemed necessary to remove all soil to a depth of 1m, before treating the area with a herbicide and replacing the soil. More recently, the approach seems to be to use a combination of cutting back the plant and applying a suitable herbicide. As the plant can grow from small sections of stem, gardeners should take care when cutting back, to do so cleanly. The use of hedge-trimmers, strimmers and lawn-mowers is a definite ‘no-no’.

There are several licensed companies who offer a treatment plan should you find the dreaded weed in your garden. Treatment companies should be licensed. A modern treatment plan will generally take several years to complete and will create minimal disruption.

Do I need to tell a buyer if it is my Garden?

Until recently the answer to this question was ‘not unless they ask’. However, more recent Law Society guidance, which came out in the summer of 2013, recommends that solicitors should always ask the question when acting for a buyer. The chances are, if you don’t tell your buyer at an early stage, it will come out in the wash when their solicitor reviews the replies to his enquiries. Our advice is that if you have Japanese Knotweed in your garden, it would be a better to put a treatment plan in place and come clean with your buyer at an early stage.

What should I do if I think I’ve spotted Japanese Knotweed in my garden or somewhere else?

If you have knotweed in your locality it is inevitable that it is going to need to be dealt with at some point. Our advice is to call out an expert if it is on or near your own property.

If you plan to deal with the issue yourself, take advice and do your research before commencing any work. Taking the wrong approach could exacerbate the problem.

If it is on someone else’s property, then the situation becomes more complex. Even the Environment Agency have no power to act, so if your neighbours are not willing to deal with it, our advice is to take legal advice. (Your only rights are for the ‘quiet enjoyment of your own property’ under common law. So it could mean taking civil action against the land-owner as no law has been broken).

Buying a house with Japanese Knotweed

Assuming your solicitor has followed the Law Society guidance, you should find out before exchanging contracts if the existing owners are aware of any Japanese Knotweed at the property. Unlike a house that has suffered subsidence or structural issues, the previous existence of Japanese Knotweed is unlikely to significantly affect the future value of the property, after the treatment has been completed.

An important factor when buying an affected property is going to be whether there is a treatment plan in place, how much this will cost and how long it will need to continue for. In many instances, it might be reasonable to ask for a reduction in the price being paid to cover the cost of any future treatments.

Some mortgage companies will not offer a mortgage on an affected house, but others will. Speak to your financial advisor before making a mortgage application and make sure they have checked that the lender they are recommending is not going to decline the mortgage.

If you are looking for any further advice regarding property, please feel free to give us a call.