How long can you safely keep tyres on a car before changing?

[G864 TST]

Strange question I know - I do very little miles in my (pride and joy) GTI
4 years old with just under 10k on the clock
The tyres look in great condition but how long before I should consider changing them due to natural deterioration 
I'm looking for an excuse to buy some monza shadows 

[bacillus]

iirc I saw an video in the past stating that dealers shouldn't sell new tyres older than 6 years because the tyres degrade over that time period and can be dangerous if used on the road.

[Wayne]

If it is sitting around then I would say 4/5 years max.

[2007GTI]

yes I heard 4/5 years.

the rear original factory tyres on my car (22k) are cracking badly on the edges and although they have 5mm left, they will need changing before they get down too much.

[Organisys]

Telephone the tyre manufacturer and ask?

They will tell you how to identify when the tyre was made too.

[seiko]

when I bought my skyline gtr a few years ago it had good looking Bridgestone tyres all round, but handled like it was on ice, took it to my local tyre dealer to change them and he had a hell of a job to get the off the rims because the compound had gone in them and they were rock hard and dangerous, even though they looked good with loads of tread