Discharge of contractual liability 139and so the decorator was paid £750, but then had to pay damages of £56. By contrast, in
Boltonv Mahadeva (1972)the contract was to install central heating in a house for £560.
Defects in the work would have cost £174 to put right. The Court of Appeal held that there
had been no substantial performance and so the installer received no payment at all.
Acceptance of partial performance
A third exception to the general rule arises where partial performance was freely accepted by
the other party. However, this acceptance must arise as a matter of choice. For example, in
Sumpterv Hedges (1898)the claimant had agreed to build two houses for the defendant for
£565. After doing work to the value of £333 the claimant was forced to stop work because he
had run out of money. The defendant finished the work himself. The court held that the defend-
ant did not have to pay the claimant for the work he had done. The defendant’s act of finish-
ing the work did not indicate that he had freely accepted the claimant’s partial performance.
Prevention of performance
A final exception to the general rule arises where one of the contracting parties prevents the
other from fully performing the contract. The party who is prevented from fully performing
will be paid the amount deserved for the work done. This is known as a quantum meruit
payment. In Planchév Colburn (1831), for example, the claimant had been commissioned
by the defendant to write a book. The book was on costumes and armour, part of a series
called the Juvenile Library, and the claimant was to be paid £100 on completion. The defend-
ant cancelled the series when the claimant’s book was partly written. The claimant was
entitled to a payment of £50 for the work he had done.
Figure 5.2 gives an overview of how contracts are discharged by performance.
Figure 5.2Discharge of contractual obligation by performance