What fitting is neede for 25 KG mirror

[ray316]

I have a mirror l want to put up on a wall that is dob & dab plasterboard with breeze blocks behind that.
The mirror is heavy and only has one keyhole fitting at the back , the keyhole fitting is small so wouldn't take a large head screw or coach screw..
Any suggestions please on how to go about . The mirror is new so l presume one fitting hole with the right wall fitting will hold the weight ..
The mirror is 4ft in diameter.

 

[rsgaz]

How many millimetres are these two dimensions?

 

[ray316]

Well a M6 coach screw head not go through the bottom hole ..

 

[foxhole]

I use 120mm screw , smallest head available will usually fit if not I grind the head down to size.
This screws straight thru my insulated plasterboard into thermalite blocks. Hold most things including curtain rails. If its not holding I remove and hammer in 6mm dowel to 120mm which gets a firm hold.

 

[bernardgreen]

I would NOT trust that fixing. The three screws used to fix the bracket to the plywood could easily split the plywood as they are so close to the end of the plywood..

If you want a safe single screw fixture then replace that bracket with a longer one with fixings to the ply woodspread over a larger area.

 

[charliegolf]

I'd use 3 of these https://www.screwfix.com/p/plain-mirror-plates-electro-brass-32-x-32-x-32mm-10-pack/14529#_=p

(at the 3, 6 and 9 o'clock spots on the ply backing; and them fix them with these:

https://www.screwfix.com/p/easyfix-hollow-wall-anchors-8-16mm-m5-x-52mm-10-pack/12229#_=p