If the knotweed originates from your garden, you may be accused of negligence by failing to take measures to protect your home. If the knotweed originates from a neighbour’s property or land, then your insurance provider may be willing to pursue the neighbouring landowner for the cost of the claim. But again, this changes from provider to provider. The amount that can be claimed will vary depending on the damage caused to the building and will not cover treatment or removal costs.