Wireless Sensor Networks (WSNs) are among the integral parts of the future Internet of Things (IoT) with many technologies developed to handle the communication between devices in WSNs. One of the prominent open protocol stacks, IPv6 over the Timeslotted Channel Hopping (TSCH) mode of IEEE 802.15.4 (6TiSCH) enables higher reliability and scalability through scheduled communication. Still, the industrial adoption of IoT is often hindered by the absence of strict latency guarantees. Despite numerous Scheduling Functions (SFs) proposed for 6TiSCH are tackling this issue, a comprehensive analytical framework to evaluate 6TiSCH network performance in a fast and precise manner is still missing. This work presents an approach to model the latency over multi-hop communication in TSCH for periodic, homogeneous traffic.