A fused filament fabrication three dimensional printing system includes a build platform, an extruder for one or more deposition materials, the extruder including at least one nozzle movable relative to the build platform, and a controller configured to control the relative movement between the build platform and the nozzle, and to cause material to be extruded out of the nozzle to form a 3D object on the build platform. The build platform includes a first plate on which the 3D object is formed, a second plate that is positioned vertically below the first plate and defines at least one gap between the first and second plates, and a heating element that is configured to heat the second plate. The first plate defines at least one opening that is configured to allow passage of material extruded from the nozzle into the at least one gap between the first and second plates.