Hidden turned-off decking affects joists under

[KeesW]

I need to create a floor framing plan and have drawn its joists. A part of my floor is to be covered by spaced decking boards and I have these on a separate layer. When this layer is turned off the joists still show partially dashes rather than as complete solid outlined framing members as required. I remember coming across this issue some years ago but have forgotten where it is and how I can turn it off. Any suggestions?

[Lingwisyer]

Use a GO to override the Linetype of your joists in your framing plan?

[Glori_aaa]

Did you try changing the floor plan display and projection mode? 
(This can be found in your element settings - Ctrl-T)

[Erwin Edel]

Also check the model view options, there are settings for showing beams and columns as dashed if they are below a slab.

[KeesW]

Thank you Erwin. I know that but expect to see my beams created with solid lines show as solid lines when I hide the decking. I have the same beams under a plywood cladding and they show with traditional dashed hidden lines. When I hide the cladding layer, beams show with solid lines. When the same cladding over the same beams, but comprise spaced decking as cladding, beams present with poorly hidden dashed lines with decking in place,  and even poorer dashed lines when the decking is hidden. 

[KeesW]

Thank you all for your comments. I think that I have identified the cause and it is not what anyone suggested. Instead the problem appears to be related to the use of intersection group numbers. Changing the group number of the floor joists from that of the floor decking causes Archicad to show both of them correctly. The joists under the decking and flat plywood floors still show with solid, rather than hidden lines, but this might be graphic override issue and I will check out.