wire size recommend....

[alung92]

I want create a smart home system using raspberry pi 3 to control my lightning switch by using relay 5v (output). My input will signal will be PIR sensor (3.3v-5v). which mean 5 input(PIR sensor), 5 output(relay).

My question is i look through the port for sensor and raspberry pi 3 seen like the wire sizing only compatible for 1 core pvc cable. is it ok if i used it for wiring my home wiring system for raspberry pi 3 design. my house is double story which mean the wire can be used up very long , but i will consider about the voltage loss and heat.

Please give some advance , or recommend the wire size.

Thanks in advance.