According to examples, a build module may include a housing, a build material chamber, and a build chamber. The build material chamber may be positioned beneath the build chamber in the housing and may include a moveable support member, in which a build material distributor is to supply successive layers of build material onto the moveable support member from the build material chamber. The build module may be removably insertable into a build receiver of an additive manufacturing system to allow the additive manufacturing system to solidify a portion of the successive layers received onto the moveable support member during the solidification process of the build material. The moveable support member may separate the build material chamber from the build chamber to block build material from the above the build material chamber from being received into the build material chamber during a solidification process of the build material.