Baffled by extending WiFi from Asus RT-AC88U

[Jason66]

Hi, this community has helped me before so I thought I'd bring a new problem - I've extended the hkuse and built a new outside space, trouble is, it's as far away from my home office and the router as I could get. WiFi coverage is patchy.
I also had an idea to put a spare old PC in the garage to play music from my NAS, the garage is now part of the extened house and you guessed it, no WiFi.
I thought I would extend the WiFi somehow, I can't really run cable now all the walls are plastered and decorated, and the floor is laid. In an ideal world, the solution would be easy plug and play.
So the question is, what are my options to get WiFi extension without wires? OK i know I'll need power . I quite like the RT-AC88U but I'm not especially precious about keeping it.
Currently we have a few things on the network- about 4 PCs, 3 or 4 TVs, a bunch of phones and laptops plus a Raspberry PI NAS with Plex. There's no serious gamers here.
I have to admit to being confused by the sales patter and whilst I like a low cost DIY approach i will invest if it saves me time and hassle

 

[L&LD]

An RT-AC86U (used as the main router) and the RT-AC88U used as an AiMesh v2.0 node may be all that is needed.

Put some numbers to your statements above (how far is 'as far away as I could get.').

With a little creative re-locating of the main router and the exact placement of the node, you should be very happy with the results in the garage.

Ideally, you would run an Ethernet cable (at least two...) to the space you want the AiMesh node in. Running the cable on the outside of the buildings is an option if done correctly.

If the RT-AC86U + RT-AC88U doesn't prove to be a good match for your wireless environment, consider 2x RT-AC86U's.

You can go all the way up to 2x RT-AX86U's for the best performance (low latency, highest bandwidth possible).

 

[eibgrad]

As @L&LD has alluded to, knowing how far is key, because in some instances, your best bet is to use a prosumer-grade wireless p2p (point to point) bridge to extend your coverage, esp. over a wide patio, rather than trying to *force* consumer-grade routers to handle the job.

 

[Jason66]

Thanks for the replies. The base router is in the study which is where the Virgin hub is located (in modem mode). There are two internal walls and one external wall between the office and the covered patio area - it's about 15 meters, there is quite a lot of metalwork in the way. The garage is about the same distance but has another couple of brick walls in the way including a big aluminium roller shutter door.
If I were to relocate the router away from the Virgin Hub, is there any restriction on the length of Cat 5 I could use?
Realistically, I can't take Cat 5 out of the study without some issues with the management (she likes good WiFi but if I start drilling holes, she will get iffy!)
There may be an option to go outside the office and back in the garage with Cat 5 - you've got me thinking now

 

[L&LD]

I'm using 100' of store bought (ie. pre-terminated) Ethernet cable with just Cat5e specs with no issues between 2x RT-AX86U's.

 

[dlandiss]

is there any restriction on the length of Cat 5 I could use?

The length limits for Ethernet depend somewhat on the speed you require, but for the use you have described it should be 100 meters (330 feet):

https://www.showmecables.com/blog/post/cable-distance-limits-data