I'm installing some 12volt downlights in a small toilet in a gap above a sink. I realise I'll need to create a void using a simple wooden frame to house the transformer above each light. How deep should I make it?

Thanks

Paul, did you buy the lights yet? Hampton Bay makes what you describ but they also make a 120v version which needs no transformer.

I'm installing some 12volt downlights in a small toilet in a gap above a sink. I realise I'll need to create a void using a simple wooden frame to house the transformer above each light. How deep sould I make it?

thanks
That depends of course on the size of the transformer.
As you did not provide any details on either transformer or power requirement of the downlights (why not use an electronic fluorescent tube light?), it is impossible to advice you.
;)