Downlighters & a main light?

[sparkyspike]

Would I need a three way dimmer to control all and the bedside lamps also?

You could do. If they are just for reading, then you may as well have switches on or near the lamps, then a 2 gang dimmer switch for the other lights. If you are using the lamps for mood lighting, then a 3 gang dimmer would be a good idea.

 

[ban-all-sheds]

Oh right, would there be a gap between the cornice and ceiling though?

That would be best, as it will allow the light to come out.

Would this not gather dust/dirt etc?

And dead insects.

 

[holmslaw]

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