Answer by  
                                                                                          TravisUSMC (979)
                                                            
                          
                          
                                                          If you are not looking to do a major floor rebuild you can only approach this one way. Using a long level you will need to loosen boards and use shims at certain points. Make sure to use small shims and constantly check your level. Do not re-nail any boards until you are fully leveled.