water pipes spanning skyligh
 

water pipes spanning skylight
hi guys,
i have this situation where i need to retrofit a bracket which is capable of supporting two 100 dia (4") water pipes spanning across a skylight found in the attachment.
i think the best way to do this is to anchor two angles back to back to the existing concrete parapet, removing some sheeting from the existing roof and site welding a cleat to the existing roof frame. after this is installed, flashing is provided around the angles for waterproofing.
has anyone had any experience supporting waterpipes and what is the best structural steel section to use?