(concurring). I concur with the majority that in general it is appropriate to remand cases involving breaches of the warranty of habitability to the Superior Court to allow it to determine the portion of rent to be rebated to the tenant. However, it seems to me that under the reasoning of Boston Housing Authy. v. Hemingway, *313363 Mass. 184 (1973), the rental value of the unit must be zero when the board of health condemns the apartment. In the Hemingway case the Supreme Judicial Court recognized that in an urban society “the essential objective of the leasing transaction is to provide a dwelling suitable for habitation.” 363 Mass. at 196-197. The delivery of an apartment in habitable condition is the consideration for payment of rent. As the promise to pay rent and the promise to maintain the apartment in a habitable condition are mutual and interdependent covenants, the breach of the warranty of habitability is “a partial or complete defense to the landlord’s claim for rent owed for the period when the dwelling was in uninhabitable condition and the landlord or his agent had written or oral notice of the defects” (emphasis added). 363 Mass. at 202-203. The court in Hemingway explicitly recognized the possibility of a rental value of zero: “If the tenant elects to stay on until the end of the term and the landlord makes no repairs, the tenant will be liable for the reasonable value, if any, of his use of the premises for the time he remains in possession” (emphasis added). 363 Mass. at 202. See also McKenna v. Begin, 3 Mass. App. Ct. 168, 171-172 (1975) (“it is possible, in a given instance, for substantial defects to reduce the fair rental value of the premises to zero”).
In the instant case the tenant paid for his own heat, hot water, and electricity. Thus the consideration given in exchange for the rent was the structure — which was so defective that the board of health condemned it as unfit for human habitation. It would seem that in such circumstances there is no obligation to pay rent. Accordingly, where the unit was unfit for human habitation, as here, there was a failure of consideration and the rental owed — the value of the apartment — should be zero.
Moreover, as the tenant paid for utilities himself, and the landlord made no outlays for repairs, there is no unjust enrichment to the tenant in abating the rent, whereas requiring payment of rent would unjustly enrich the owner.
Whether or not the rent is abated completely from the *314beginning of the tenancy, public policy considerations dictate that it must abate completely after the condemnation of the unit. The decision of the board of health — as an administrative body which is presumably more expert than a court in judging the condition of apartment units — that the unit was unfit for habitation should be conclusive in the court’s determination of the habitability and value of the unit. Even more importantly, to permit payment of rent where a unit has been condemned is to frustrate the policy of the administrative agency (the board of health) of preventing occupation of buildings that are unsafe and dangerous to health because awarding rent for such a unit encourages the owner to continue to rent the unit despite its condition.
Finally, where a contract is in violation of a statute and public policy, it is illegal and unenforceable. A lease agreement which is knowingly made despite the existence of violations of the sanitary code which make the dwelling uninhabitable is an illegal agreement which is unenforceable. Brown v. Southall Realty Co. 237 A.2d 834 (D.C. 1968). See Diamond Housing Corp. v. Robinson, 257 A.2d 492, 494-495 (D.C. 1969), revd. 463 F. 2d 853 (D.C. Cir. 1972).