I used to live quite near there and have done a similar 2 leg flight on many occasions. Then drive for an hour. It's quite an exhausting journey and I don't think I'd have fancied a 5 hour drive. I think I would book a hotel for a night.

Vancouver is a lovely city. Could you have a few days there before you drive on?

We got a flight to Calgary and return flights from Vancouver on the way back. Had a hire car that took us on a meandering route via Banff and Jasper etc. The most amazing scenery! Definitely travel by road as you'll miss the scenery if you take an internal flight.

Is there anywhere in particular you're interested in? Vancouver is a nice city but the national parks are the must sees

Could you get a greyhound bus and pick up rental car at destination?

Sorry, just seen you're visiting family. I did read your post but I don't think it went in! 🤦‍♀️

Is Calgary closer to your destination?
Is there a flight via Europe (Amsterdam, Frankfurt etc) which connects with the airport closest to yoir family? That would be similar to travelling via Heathrow. Or a flight via Toronto? Google Flights and Skyscanner are good for finding flights.

If not, I would overnight in Vancouver to shake off the jetlag before starting the drive.

Depends on how much time you have at the destination. I would say go for the extra flight unless you have another reason to stop in Vancouver, or drive the 5h (scenery etc).

Flights with 2 stopovers aren’t particularly enjoyable, especially when there’s jet lag involved, but it’s honestly not so bad and it gets you there quicker.

One of my recurrent work trips involves a 2h + 14h + 2h flight. Going east is a bit worse (so coming back to the UK for you), because you’re ‘skipping a night’ instead of just prolonging the day, which is what happens when travelling west.

But honestly, it’s logistically so much easier because you just check in for the first flight and know you aren’t leaving the airports at all, queuing to pick up a car, figuring out satnav/google maps in another country where you might not have good data, swapping to driving on the other side after 10h on a plane… All you might need to do is clear customs and walk your bags from one belt to the other when entering a new country, but it’s very simple. It’s also going to be quicker exiting the airport at the smaller destination airport, than doing so at a big hub such as Vancouver, where the queues and crowds will be larger.

The third flight always feels like it never ends but you’re so close at that point that you easily push through. It’s also often much cheaper to book an extra transfer than take a direct flight or do just one stopover… Airlines are funny like that!

Forget to say, direct was with Air Transat.
www.airtransat.com/en-GB/cheap-flights-uk/to-canada/manchester-vancouver?search=flight&flightType=RT&gateway=AIRPORT_MAN-AIRPORT_YVR&pax=1-0-0-0

Sorry, just checked the link and the flights aren’t direct now!

I lived in BC for a few years. Depending on where your final destination is I'd either spend a few days in Vancouver itself before/after, or do it as connecting flights. The long haul flight and 8hr time difference will make it a difficult drive. Driving 5hrs over there can be mind numbingly boring, and dsngerously so especially when you're on the 'wrong' side of the road to the UK and with the amount of big trucks on most of the regional highways.

I'd definitely not do the drive when you arrive. You might be ok to do it the next day - we woke early and then took the ferry and drove to Tofino which is about a 4 hr drive and were fine.

What would be the closest airport to your final destination? Like a PP said, check google flights for best routes and prices, or if you let us know the name of the airport we might come up with alternative journeys.

No experience of the journey but live in Vancouver. I’d stay a day or so just to get some rest and let your body clock adjust a bit before driving.

I don't know where exactly you're travelling to that's 5 hours away but guess it could be similar to us. We have family in the Okanagan and we've done many different options and combinations including flying via Calgary and then another flight to Kelowna (we've also flown to Vancouver and then connection to Kelowna). What we quickly realised is that arriving with family after a lengthy flight and tetchy kids is not the best. We prefer a chance to decompress, plus we also need to hire a car anyway so this is what we do:
Fly to Vancouver either directly from Heathrow or do look at a US airline where you can fly to Portland and then take a connection to Vancouver (only about 50 minutes in the air) and sometimes cheaper. Either way plan to get to Vancouver in the evening and stay at an airport hotel. Get through customs, go to hotel, eat, sleep! Collect your rental car the next morning (big diner breakfast!) and then do the drive. We have found this is the best way to break up the journey and relax/sleep and feel more like ourselves before we continue the journey the next day. If by the same coincidence you're also going to the Okanagan then make sure you stop in Hope en route! The scenery the whole way is beautiful.

We did it a couple of years ago. You’ll be exhausted. Either get a flight, or stay fir a couple of days - it’s an interesting city to visit; so would recommend the latter.