Infestation of Rats, Mice and Other Pests


Sometimes a tenant's property may suffer an infestation of rats or mice, and tenants will often seek that the landlord rectifies the situation. But is it the landlord's duty? 

Also briefly covered later in this article (as the principles are similar) are wasps, bees, pigeons and bed bugs.

There is no legislation or common law duty that specifically requires landlords to rid their properties of vermin thus in the absence of any express term in the tenancy agreement the tenant may have to request assistance from the local authority. Depending on the circumstances, local authorities may look to tenants/landlords to take action and pay for the eradication of the pests. [Paragraph 2 Dealing with infestations in privately rented property - House of Commons Standard Note SN/SP/6041]

Rats and Mice

Fit for human habitation

A case brought under an old provision, namely sections 14 and 15 of the Housing, Town Planning, &c., Act, 1909, held that the presence in a dwelling from time to time of rats, even in considerable numbers, is not a breach of the implied covenant that the house is fit for human habitation. However, it seems it would be if the rats infested the house because they bred there, were regularly there, and, as it were, formed part of the house—[Stanton v Southwick [1920] 2 K.B. 642].

Here the question is whether there was evidence on which the judge could find that the house was infested with rats in the sense that they bred there, were regularly there and, as it were, formed part of the house. In my opinion there was no such evidence. The case was fought upon the footing that the rats had their home in the sewer passing below the house, that from the sewer they made incursions into the house in search of food, and that that was how they were found to be in the house. The judge was, in my view, wrong in law in holding that the presence in the house of the rats to that extent and in those Conditions constituted or could constitute a breach of the statutory condition.

However, the legislation for fitness for human habitation has been considerably updated since March 2019, but there has yet to be any case law. 

Pests are specifically part of the new legislation. Still, as with all aspects of the legislation, it only applies if "it is so far defective in one or more of those matters that it is not reasonably suitable for occupation in that condition".


In Carstairs v. Taylor L. R. 6 Ex. 217, the landlord let the tenants use the lower part of a house as a warehouse while the landlord occupied the upper part. 

A rat or rats gnawed a hole in a water cistern in the upper part of the house, and water poured down and caused damage to the tenants' goods in the warehouse. At that time, the warehouse was not in a fit condition to be used as such. 

Counsel for the tenants argued that "the defendant [landlord] was liable on the ground of contract, he has impliedly undertaken that the warehouse let to the plaintiffs [tenants] shall be suitable for the purpose for which it is let, which cannot be said to be true if it is accessible to water or rats." 

Dealing with that argument, Kelly C.B. said at 220:

“Clearly there is no duty on the occupier above, whether he be landlord or only occupier, to guard against an accident of this nature. It is absurd to suppose a duty on him to exclude the possibility of the entrance of rats from without. The case of a ship is totally different: it may be possible to insure freedom from rats in a vessel; but it is impossible to say with respect to warehouses generally that this can be done.”

Prevention of Damage by Pests Act 1949

Under section 3, Prevention of Damage by Pests Act 1949, the occupier (usually the tenant in this context) of any land must give to the local authority notice in writing if it comes to his knowledge that rats or mice are living on or resorting to the land in substantial numbers. This does not apply to agricultural land. 

A failure to give notice is a criminal offence. 

Under section 4, the local authority may serve on the owner or occupier a notice requiring him to take, within a period as specified in the notice, steps for the destruction of rats or mice or otherwise for keeping the land free from rats and mice. The notice may require the application to the land of any treatment or the carrying out of any structural repairs or other works specified. 

If a landlord is served with such notice, then the landlord will be liable to rid the property of rats or mice as per the notice unless they successfully appeal to the Magistrates Court as a complaint. There are several grounds of appeal, but the most likely in the context of this article is:

That the notice might lawfully have been served on the occupier of the premises in question instead of on the owner, or on the owner instead of on the occupier, and that it would have been equitable for it to have been so served.

Please refer here to our detailed article on appealing against a Prevention of Damage by Pests Act 1949 notice.

Repairs and structure

Amongst other things, it is an implied term of a short lease (less than seven years) that the landlord shall keep in repair the structure of the dwelling, including the drains, gutters and external pipes. 

This does not pose a duty to a landlord to rid a dwelling of rats or mice. Still, if the infestation results from disrepair of the structure (for example, a hole in a wall or a faulty drain), the landlord will have to repair the hole in the wall or faulty drain. 

If the infestation is consequential to the disrepair, it will be advisable for the landlord to also rid the premises of rats or mice at the same time. 

In the Stanton case above, which discussed fitness for human habitation (for which the legislation no longer exists, so perhaps now irrelevant), it was suggested in the judgment that there would have been a breach of the implied term if the house was infested with rats in the sense that they bred there, were regularly there and, as it were, formed part of the house. 

Although it is accepted that this judgment refers to legislation which no longer applies, it is, in our view, possible to read this to mean that if the infestation becomes "part of the house", it becomes "part of the structure", and so requires remedy by the landlord. If this view is correct, then in theory, at least, if an infestation has become part of the house (or part of the structure) due to its size and nature, it could be argued such an infestation is the responsibility of the landlord. 

For the avoidance of doubt, this is just a theory, and no modern case law suggests this would be the position. Even if this were the case, it was the tenant's fault that the infestation had occurred due to leaving rubbish and food out. For example, a landlord is not liable to carry out works or repairs for which:

the lessee is liable by virtue of his duty to use the premises in a tenant-like manner, or would be so liable but for an express covenant on his part ... [section 11(2)(a) Landlord and Tenant Act 1985]

Housing health and safety rating system (HHSRS)

The HHSRS is reactive legislation, so there is no requirement for a landlord to carry out works under its provisions unless the local authority serves an appropriate notice or order. 

However, the statutory guidance has some valuable points regarding preventing pests.

The exterior of the dwelling should be free of cracks and unprotected holes. Where breaches of the walls or roof are necessary, grilles or other methods should be used to protect these. Any spaces within the dwelling such as service ducting, roof spaces and under floor spaces and service ducting, should be capable of being effectively sealed off from the living area. There should be means of access to these spaces for treatment in case of any infestation. Generally, dwellings should be designed and constructed so as to reduce, so far as is possible, gaps or voids that may be inaccessible to the dwelling occupants, and which may provide harbourage for pests. Particular attention should be given to the siting of such fittings as hot water tanks and boilers. The design and construction should reduce, so far as is possible, any means of access by pests from the outside into the dwelling. All openings into drains should be sealed with an effective water seal; this includes openings such as into the wc basin and drainage inlets for waste and surface water. T

o prevent mice entering there should be no holes or gaps in excess of 6.25mm. Service entry points should be effectively sealed as should any points in walls penetrated by waste, drain or other pipes or cables. There should not be any holes through roof coverings, eaves and verges which might allow access into the roof space of rats, mice, squirrels or birds. Any necessary holes for ventilation should be covered with grilles. 

There should be suitable and sufficient provision for the storage of refuse awaiting collection or disposal outside the dwelling. There should also be suitable and sufficient provision for the storage of household refuse within the dwelling. The storage provisions should be readily accessible to the occupants, but sited so as not to create a danger to children. The refuse facilities should not cause problems of hygiene, nor attract and allow access to pests. [paragraphs 15.20 - 15.23 HHSRS Statutory Guidance]

County Court

There have been several county court cases where compensation has been awarded to tenants regarding infestations of rats or mice. However, it's unclear what the precise facts of each case were without seeing the actual judgments.

In Bernard v Meisuria, Central London County Court 22 November 2010, the tenant brought a claim for disrepair, which included a rat infestation from 2005 to 2009. The court found that the rat infestation emanated from drains in disrepair and ordered the landlord to pay £20,000 for the rat infestation, including special damages. This was because a property infested with rats had little rentable value and the award seems to have represented almost 100% of the rental value. 

In Frederick v. Simpson v. Frame Willesden County Court, 11 July 2011, which involved a counterclaim by the tenant against a claim for possession based on rent arrears, the court awarded a 15% diminution of the rental value due to an infestation of mice, mainly in the common parts. 

In another counterclaim by a tenant, Harwood Properties v. Remuinan Brighton County Court, 18 October 2011, the court ordered a 20% reduction in the rent for the period February to August 2011 due to a rat infestation.

Other pests

In respect of other infestations such as wasps, bees, pigeons and bugs, the position is mainly identical to that discussed above regarding rats and mice, except with smaller animals such as wasps or bugs, there may be no structural defect causing the infestation, so it may be nobody's responsibility to remedy the infestation.

Wasps and bees nest

In most cases, wasps and bees appear through nobody's fault. 

The landlord may be under a duty if the infestation is within a mortar crack, so the mortar on the structure needs repair. Still, if the building is in good repair and a nest appears, there seems to be no reason why a landlord must get rid of the infestation. 

Of course, in many cases, the landlord will choose to get rid of the infestation, which is good advice as it keeps the tenants happy and perhaps gives the landlord an easy life!

Bed bugs

Bed bugs in a furnished property at the time of a tenant moving in have been held not to be fit for human habitation, so the landlord was in breach of that implied term [Thompson v Arkell (1949) 99 L.J. 597.] 

Bed bugs long after a tenant has moved in is unlikely to be a landlord's duty and most likely the tenant's, but as always, it will depend on the individual circumstances.


Pigeons will most likely be the same in principle as a wasps or bees nest, and the landlord will not be under a duty to resolve the situation unless the landlord is responsible due to structural defects etc.

Damage caused by infestation

If damage is caused by an infestation so, for example, a mouse chews through wires on a boiler (a genuine fault I once had) or pigeons break slates on a roof to enter a loft area (another problem we regularly have), the landlord will be under a duty to repair the broken boiler or slates on the roof but not necessarily in these examples rid the property of the mouse or the pigeons that caused the damage (although it would be sensible in this type of situation to avoid repetition of the problem).

Other General Matters

Tenancy agreement

If there is a clause in a tenancy requiring one party or another to rid an infestation, the tenancy will need to be followed. If it is the tenant's duty, that will, in most cases, be enforceable as long as it wasn't the landlord's fault that the infestation occurred (for example, there is disrepair).

Nobody at fault

Where nobody is at fault, nobody needs to rid of the problem. If the tenant wishes the problem to go away, then it will be for the tenant to make the necessary arrangements unless something in this article requiring a landlord to do so is relevant.

Common Parts

A tenant will never be liable to rid pests within common parts, which will include a shared garden, yard or staircases etc. (and for this purpose, we mean individual tenancies on flats or rooms, not a single joint and several tenancy). 

A landlord may be liable if the principles outlined in this article apply (structural defect etc.). 

In respect of rats or mice in common parts and assuming no one is at fault, it would seem that a landlord will nearly always have to rid of the rats and mice because the local authority could serve a notice under the Prevention of Pests Act 1949. There would be no appeal on the grounds of serving on the occupier if the occupier had done nothing wrong.

View Related Handbook Page

Landlords’ Responsibilities for Repair and Maintenance

In addition to any repair responsibilities explicitly set out in the tenancy agreement, common law and statute will imply terms to the agreement between landlord and tenant.