Wireless sensors and actuators are increasingly used to automate residential properties. Such home automation (HA) systems are generally built around simple devices and network protocols in order to keep system complexity and prices low. Nearly all used protocols do not provide any security mechanisms and it is possible to inject messages accidentally or on purpose. As it is not feasible to upgrade already deployed devices or to simply re-design the used protocols it is desirable to find a protection mechanism that can be used to augment existing systems. We propose to use jamming in order to prevent unsolicited messages from reaching devices in home automation systems. We demonstrate a jamming device that can be used to augment HA systems to add an additional layer of protection. The device can be integrated into existing home automation systems.