Restatement (Second) of Torts

§ 822. General Rule

One is subject to liability for a private nuisance if, but only if, his conduct is a legal cause of an invasion of another's interest in the private use and enjoyment of land, and the invasion is either
(a) intentional and unreasonable, or
(b) unintentional and otherwise actionable under the rules controlling liability for negligent or reckless conduct, or for abnormally dangerous conditions or activities.

§ 826. Unreasonableness Of Intentional Invasion

An intentional invasion of another's interest in the use and enjoyment of land is unreasonable if

(a) the gravity of the harm outweighs the utility of the actor's conduct, or

(b) the harm caused by the conduct is serious and the financial burden of compensating for this and similar harm to others would not make the continuation of the conduct not feasible.

§ 827. Gravity Of Harm--Factors Involved

In determining the gravity of the harm from an intentional invasion of another's interest in the use and enjoyment of land, the following factors are important:

(a) The extent of the harm involved;

(b) the character of the harm involved;

(c) the social value that the law attaches to the type of use or enjoyment invaded;

(d) the suitability of the particular use or enjoyment invaded to the character of the locality; and

(e) the burden on the person harmed of avoiding the harm.

§ 828. Utility Of Conduct--Factors Involved

In determining the utility of conduct that causes an intentional invasion of another's interest in the use and enjoyment of land, the following factors are important:

(a) the social value that the law attaches to the primary purpose of the conduct;

(b) the suitability of the conduct to the character of the locality; and

(c) the impracticability of preventing or avoiding the invasion.

§ 829. Gravity vs. Utility--Conduct Malicious Or Indecent

An intentional invasion of another's interest in the use and enjoyment of land is unreasonable if the harm is significant and the actor's conduct is

(a) for the sole purpose of causing harm to the other; or

(b) contrary to common standards of decency.

§ 831. Gravity vs. Utility--Conduct Unsuited To Locality

An intentional invasion of another's interest in the use and enjoyment of land is unreasonable if the harm is significant, and

(a) the particular use or enjoyment interfered with is well suited to the character of the locality; and

(b) the actor's conduct is unsuited to the character of that locality.