Sometimes, hopefully rarely, there is no nog (dwang) behind the plasterboard. I propose a screw that is placed between the boards on a free floating edge.

The screw would have a thread with a deep, sharp thread similar to a earth moving auger. Once screwed in, the head is flush or just below the board to give a good finish when plastered over. The threads bite into each sheet not allowing any independent movement in the sheets and therefore stop cracking in the finish plaster. Probably one screw per 200 mm would secure stability.

There are screw in anchors, for Drywall, that are a perfect prototype but would need adapting for this new function.
-- wjt, Dec 06 2013

I've done something like this, using ordinary plasterboard (bugle) screws in the join as you describe, for small repairs. Where the joint isn't going to be stressed much (e.g. a decommissioned ceiling fan or down-light) I'll plaster between the screws, remove the screws, then plaster where the screws were.

(Where strength is desired, I put large or small pieces of wood behind the join, and screw into them; but that's an awkward and obvious solution, and not intended to knock your idea, which would be quicker.)
-- spidermother, Dec 06 2013


This is pretty clever and has an strange, unhalfbakerylike aura of practicality.
-- hippo, Dec 06 2013



random, halfbakery