Hi Raks
take a look at this site https://www.automatedhome.co.uk/content/wiring-guide.html
I was in your possition a few years ago and you are right most of the electricians plumbers etc are not up to speed on home automation. Of course you can go to companies like Loxone but I guess you want to DIY which is why you are here.
In the years since I did my build wireless has become much more practical but you still have to think about both the power any sensor or actuator will need and the data it sends or receives. With wifi control you will almost certainly need to wire for power as it is quite power hungry, Zwave and Zigbee are much lower power so may be battery powered.
I chose fully wired and if you are stripping and re-wiring you could do the same, but it takes a huge amount of planning. However you will always find cases where the planning didn’t quite work so you will likely end up with some wireless too. Plan for Hybrid now!
What ever you choose you must keep it safe, so get familiar with the wiring regulations in your country.
On your bullet points
- List item Star wiring - good idea. Plan for dimming so if that needs an extra control wire make sure you put the right cable with the right rating in
- cat 5e is great, but where are you going to put it, you need to consider where your sensors will be placed eg PIR for movement detection, likely to be high up, what about temperature, needs to be shoulder height, what about switches on doors, or windows - need cables to the frames. Put loads of able into your porch or front door area (lock, letter box sensor, door, bell, camera etc). Think about garden sprinkler control, CCTV, garage etc So the number is less important that the location at the planning phase.
- satellite cable - not sure I would bother, I have it but don’t use it, everythign is streamed, cat5e @ 1Ghz is fine, get a reasonable switch as data rates go up
- 40mm is quite big and difficult to fit within walls. Conduit needs to be straight, pulling around more than one corner is hard and likely to damage you cable. A vertical riser is really important so you can get cable between floors, again straight and I’d say more than 40mm. Consider fire protection when using big conduit, you don’t want it to be a route for smoke.
- central manifold - yes a good idea as then powering/ controlling the actuators is all in one place. ( I didn’t!) Do make sure you insulate the pipe runs though otherwise your common run will get hot and potentially the target room will take longer to warm up. Obviously put in loads of insulation into the room ceilings, walls and floor - consider the impact on cable rating of running in insulated spaces . If heating rooms on occupancy, responsive heating is really important, so do think about electric (dead easy to control) or make sure your boiler has plenty of power (and is obviously highly efficient)
HTH
Jon
PS have a look at this for ideas of what could be automated so the wiring / planning to consider
and also part 2 from the same link