Loft question at 76 sorry

[oldie]

I have a loft in a 35 year old house which is 11mtrs x 8mtrs and has joists 3.5cm wide x 10cm deep spaced 60cm apart. My son intends to board over the joists with loft boards from B & Q but although I am sure he can do this what weight could he store?
Alfie

 

[tony1851]

Loft answer at 92;
Is it a truss-roof (ie with lots of pieces forming triangles, and joined with metal plates) or is it a conventional roof?
If it's a conventional roof, you just store things roughly where the middle supporting wall would be below; if it's a truss roof, slightly more problematic.

 

[oldie]

Here some pics: