De Lassalle v Guildford  All ER 495:
In a lease agreement, the plaintiff, Mr. De Lasalle, refused to hand over the signed counterpart lease till he was assured by the landlord and defendant, Guildford, that the drains of the house were in good order. The defendant then orally represented that the drains were in good order. The written agreement between the parties did not contain this representation or make any reference to the drains. The plaintiff brought an action against the defendant when he realised that the drains were not in good order.
1. Whether or not the representation by the landlord that the drains were in good order constituted a warranty which was collateral to the lease.
1. That the representation by the landlord was a warranty collateral to the lease.
Per the court, in addition to the terms contained in the lease, there was a collateral oral contract under which the landlord gave assurance of the drains being in a good condition and that the plaintiff was entitled to damages for breach of that term.