What is the best way to attach pine wooden balcony lats ( 11 cms wide, 90 cms high and 2 cms thick) to a metal tube railing/frame (3 cms x 3 cms, about 70 cms apart from top to bottom). The balcony is long and goes round half the house, about 30 meters. The metal frame has been treated with rust proof paint and 2 coats of brown metal paint. The wood lats have been treated with anti mould and 2 coats of exterior wood protector.

Is it best to:

1. Screw on a long horizontal wooden lat ( 3 cms wide, 1.5 cm thick and 30 meters long) on the outside of the frame first, and then to screw on each lat in turn from the outside, wood to wood.
2. Or can I screw the wooden lats directly onto the metal frame using metal screws, wood to metal. The metal is thick and this will be time consuming.

Questions:

3. What types of screws should I use? Are there any specific screws intended for just this purpose.
4. Can you glue the lats on first, to make sure they are straight and the gaps between each one is correct and then attach them using the screws.

Any other handy tips or suggestions would be much appreciated.

Cheers,

Andy