Help:What aggregates are best for flat roofs

[tin_pin_gin]

I have just bought a house with two flat roofs. One has a covering of aggregates and one is open to the elements and is beginning to show it.

I guess a layer of stones is useful to keep the worst of the weather (hot and cold) from the roofing material itself but admit to knowing nothing really about flat roofs at all.

So, my question please is what aggregates are best for the job (and even what size should they be!) and how much quantity should I be ordering for every 10sq m of roof?

Any help is much appreciated.

 

[bendylow]

6mm lime chippings from any roofing yard,1 bag will cover approx 3sqm.

 

[tin_pin_gin]

That's great - thanks for your help.