On 27 Feb, 08:05, dutchman wrote:
Whats the best way of joining 2 concrete slabs - if there is one

I have laid a slab of concrete in the garden, and I need it another 12
inches wider.

OK I can put some shuttering up and lay some more concrete, but how do
I ensure that the joint is always sound and does not give ??? Do I
drill some holes sideways into the original slab and put in some metal
bars or screw in some large dia screws and leave the heads protruding
a few inches.

Or am I worring too much.
Depends what you are using it for!
Epoxy in some 12" rebar half into each, at 600mm intervals. Or screw
in some 'Multi Monti' type bolts (Screwfix).

Phil.