Roof disappearing when I split it.

[CheezyArki]

I watched some videos on YouTube on how to make 3D roof tiles. But when I tried to split my roof, it suddenly disappeared. 

[Barry Kelly]

What disappeared, the roof or the tiles?

Tiles done with the roof accessory add-on will disappear when you split the roof.

The roof should remain and you will have to apply the accessory again.

Barry.

[CheezyArki]

The roof sir. I am trying to apply the accessories but first I need to split the roof. But when I split it, it suddenly disappeared instead of separating the roof planes. 

[Barry Kelly]

So, you have a multi-plane roof and you right click and choose 'split into single roof planes' ?

If that is the case, I have not known roofs to disappear.

Can you show a screen shot of the roof while selected before the split.

Barry.

[CheezyArki]

Here it is sir Barry,  

[Barry Kelly]

Very strange.

The roof appears to be in its own storey, but that should not matter.

I can't see anything else unusual.

The roof is grouped with something, but again that should not matter.

Does the same happen if you select and split the roof in plan?

Barry.

[CheezyArki]

Yes, I tried it in the plan also. It's the same thing happening.  
Also, I tried doing it on a new and clear file and still the same. I wonder If I accidentally pressed some settings here. I'm kind of new to this software, so I can't proceed with my exploration.  

[Barry Kelly]

I am at a loss.

You should end up with the exact same roof but in single planes.

ALT-click on the multi-plane roof so you have those settings as default, and then model a single plan instead of a multi-plane roof.

If you can see that single plane roof, then I have no idea what the problem can be.

Barry.