I tried that once. You will be weed free for one or two seasons and then the detritus that will naturally settle into the gravel or whatever hard coverage you choose will be enough for weeds to grow again. I laid down a permeable membrane, covered it with gravel and what happened was the weeds sent down fine roots through it making them almost impossible to pull out to the point where I was scraping the gravel away so I could get the weeds out by cutting the membrane around them in order to free them up for removal. So it will look nice for a year or two and then your going to have a lot of work on your hands to maintain it. This was done for a garden path so I was able to manage it for a while, then I got fed up, and tore out the membrane that I had placed and replaced the gravel. I decided that I was not going to bust a gut pulling weeds that grew through this cover. Imagine what kind of problems you are going to have with area coverage. PS I don't use weed killer or pesticides in my garden.

Welcome to GoY Johnivor...We also have a permeable membrane under our Gravel,and hardly ever get any weeds or seeds germinating ..It was previously a weed infested lawn,so it was taken up,and all rubbish etc removed as much as we could..My OH then added a good amount of sand ,and tamped it well down,before adding the membrane,and then the gravel..Preparation is the key really.. If you see only the tiniest bit of green growing,pull it up immediately,before it gets chance to make roots..I don't use weed killers or pesticides either..Ours has been there at least 10 years now,with no problem at all..There are Flowering borders all around our circular gravel area,which haven't caused any problems..If you also have some nearby,just keep them tidy,to lessen the chance of them shedding seeds,and also to keep borders weed free.
Hope these comments may help you to decide...

Be very sure you want it to be permanent because it wil be hell to remove if you get tired of it. (I get tired of it just walking past other peoples front gardens, but that's beside the point...)

No, you don't need to put down sand, I never do - you can just lay the membrane over (preferably compacted) soil. I usually walk all over the area, stepping hard on all of it, no gaps between footprints, before laying the membrane if its loose and friable or has been dug over. I may dig up again in spots where I know I'll be planting through the membrane though. Otherwise, when the soil settles and compacts down on its own over time, the membrane and stones may have dips and hollows. Even if you put sand on top too... doesn't really serve any useful purpose, many plants love to root into sand, so it doesn't suppress weeds any more than soil does.

My trouble with weeds stems from my location. Since I have a wooded area in the back of my property and across the street in the front of my home there is flower drop, seed drop and leaf drop from trees and bushes during the year let alone what the birds drop from it and it's impossible to get everything out of the gravel. If you don't have such a situation you may have a weedless base for some time.

I stand corrected,Johnivor,Bamboo is right.I checked with my OH,on reading the comments,and he didn't put sand down..He used the sand under circular pavers,he did at the same time..If you do decide on gravel.don't be sparse with it,and get a decent size ..Cats sometimes like to scratch in pea gravel..as witnessed in a neighbours garden !
Pots and tubs enhance the bare look,for different seasons..

The trick is to use a good quality membrane like Mypex. If you do use sprays it is good to spray off the area first if you have persistent perennial weeds like bindweed (which can last years under barriers!) docks, bryony etc. Be generous with the membrane, good overlap and pin it down every foot or so. Better to spend more on doing it well than have it blown off or worn out.
If you do it properly it will last for many years. But you will have some weed seeds, tree seed and debris blow in - it just happens! So blow off autumn leaves so they don't rot and become compost on your gravel. As soon as you see any green shoots - pull them out - so much easier to do a quick weed over once a month when they are tiny - than to ignore them and get rooted in monsters that disturb your gravel.
Big gravel is easier to clear debris off and less attractive to cats! If the site is on a slope - gravel will travel downhill - so either rake it back occasionally or fasten pieces of treated wood to hold it back. On a steep slope you could get another covering - it looks like a felt carpet - that can be paid instead of gravel. I have large areas of my garden done with Mypex and most of it has been covered for 15 years or so. About a third of an acre all told! My fruit garden, veg beds, pathways and a large foliage garden. Some is gravelled, some done in woodchip (replaced every third year) and some just Mypex. It saves SO much work. Good luck

If you want to know what's available regarding membranes, they're actually all called geotextiles, so if you google geotextile fabrics, you should be able to see a whole range of products varying in grades, thickness, etc. Some are designed to go under driveways, and are stiffer, thicker and white, but you'll see more choices than what's available at the garden centre.