You can do at the configuration level. For a client, you would want to adjust the sendTimeout attribute of a binding element. For a service, you would want to adjust the receiveTimeout attribute of a binding element.
<system.servicemodel>
<bindings>
<nettcpbinding>
<binding name="longTimeoutBinding">
receiveTimeout="00:10:00" sendTimeout="00:10:00">
<security mode="None" />
</binding>
</nettcpbinding>
</bindings>
<services>
<service name="longTimeoutService">
behaviorConfiguration="longTimeoutBehavior">
<endpoint address="net.tcp://localhost/longtimeout/">
binding="netTcpBinding" bindingConfiguration="longTimeoutBinding">
</endpoint>
</service>
</services></system.servicemodel>