What depth of tarmac should be laid

If i was to do the job with the information i have just been given,i wiuld rip it all up and start a fresh. as i do not know the weight of some of the vehicles using the road. The method used in the description ,is just a cost saving method that doesn't last many years.

Hi, mmm Not sure about this one soil and scalpings ? number one. whats the soil like? is it compacted? whats the depth of scalpings? are they compacted? I would like to come and have look and tell you the best way to do a job that will last, and doing it in the most viable way possible, but its certainly not worth doing cheap cheap and then its breaking up after a couple of years, it looks like there are enough of you to pay for a good solid job, without completely ripping it out and starting a fresh. Whatever you do make sure you have a solid foundation or the job just won't last. Don't know where in the country you are. But if you are not far away I would come and give you some ideas on how to go about doing a proper job at the right price. Hope I have helped with your question, we have been laying asphalt and tarmac surfacings in the East Midlands for many years, so we certainly know our stuff Anyway take care and good luck it. Ken