Home Network VLAN Question

Hi,

I have a question regarding my current home network and if it may be possible to create VLANS.

I have a pretty traditional 'flat' home network structure in my townhome. I have ethernet jacks on each floor that terminate in the basement and plug into ports on my (currently) unmanaged GS24T V3 switch. Port 1 of the switch is connected to my Asus RT 89X router and from there to my ISPs cable modem. All DHCP is being handled by the router and all devices are on the same network (192.168.x.x /24).

The network has a lot of 'noisy neighbors' such as smart devices, printers and VoIP phones connected to it and they are not all on the same floor of the house. I have unmanaged switches on each floor that connect to the ethernet jacks and these connect to the GS24T in the basement.

What I'd like to be able to do is to create some VLANs that will logically constrain these devices and keep the signal to noise down a bit.

Here's a use case:

I have a VoIP phone on the first floor that is plugged into port 5 of an unmanaged switch. This connects to the ethernet jack on that floor and eventually plugs into port 20 of the GS724T. I have other devices connected to that unmanaged switch on the first floor. I would like to put the VoIP phone into a VLAN. The VoIP phone uses an old fashioned ATA to do its work.

My thinking is that if I create a VLAN (let's say 30) on the GS724T, and make port 20 a member of it, then replace the unmanaged switch on the first floor with a managed 8 port switch, create a corresponding VLAN 30 on that switch and make port 5 a member of it I should be heading down the right path?

If this assumption is correct, my next question is related to port tagging. As indicated above, port 20 on the GS724 is where the first floor switch connects and there are devices on that switch that would be members of other VLANS, so I'm assuming that one would NOT be tagged? Would I just need to tag port 5 on the first floor managed 8 port switch?

It would also be necessary for some VLANS to 'talk' to other VLANS (the Server VLAN would need to talk to the workstation VLAN for file transfers, DNS etc.) and EVERYTHING would need to talk to the Internet via the Asus router, so any advice for setting that up would be gratefully received.

I intend on leaving everything in the same network address range, so I don't have to mess with anything on my Asus router

My sincere thanks in advance for any advice/guidance