Roof racks and weights

Hi all,
I have seen a roof rack somewhere that states it will take 300kg on a Disco2?
I know stuff fits, but is it legal to have a shedload of stuff on your roof?
how much weight is the car designed to take?
if you have 2 sets of 50kg roof bars, does that mean you can take 100kg (assuming you spread the weight)
three sets?
will i wake up to find the roof tent inside the vehicle?
If i equip a vehicle will it then be legal to drive down to Dover?

A properly designed and fitted roof rack will have past tests and be legal
the 300kg ones have about 8 fixing points to spread the load and it covers the whole roof area, I wouldn't want to put that sort of load on some rails, but a proper rack no problem.

I love that rack, chances are it cost more than my car LOL

Its a Safety Devices on, just grabbed a pic of google, I would think they are not cheap
Looking on fleebay £1100 new.

The rack itself might take 300kg but I suggest you check LR's max figure for roofloads - surprisingly difficult to find online - which is going to be a lot less than that.
Consequences of heavy weights high up are increase instability due to the raised centre of gravity with the potential of putting the vehicle on it's side.

Even checking the Disco's own 'heavy duty' roof rack as sold in 'expedition' gear has a maximum of 50kg,
the picture in the brochure shows what must be a rack full of empty boxes

I know in my d1 handbook it stated the max load for the roof and if I remember correctly it was 100kg but no idea if that's on the standard bars or on something else attached to the gutters.