Methods for treating a subsurface formation are described herein. Some methods include providing heat from a plurality of heaters to a section of the hydrocarbon containing formation; controlling the heat from the plurality of heaters such that an average temperature in at least a majority of a first portion of the section is above a pyrolyzation temperature; providing heat from the plurality of heaters to a second portion substantially above the first portion of the section after heating the first portion for a selected time; controlling the heat from the plurality of heaters such that an average temperature in the second portion is sufficient to allow the second portion to expand into the first portion; and producing hydrocarbons from the formation.