Answer by  
                                                                                          AlexW (407)
                                                            
                          
                          
                                                          To keep your patio slabs from cracking, you should first start with a bed of sharp sand. The bed should be about 8 inches thick. On top of that bed, use a three inch layer of a mixture of fine sand and concrete mortar. Do NOT mix with water. It will harden over time and prevent your slabs from cracking