Mounting a 23kg 55" tv to stud wall on full motion mount?? UK

Question

I've read so many forums and advice pages about this but have seen nothing definitive!

I have a 23kg 55" tv and a full motion mount that claims it can hold 40kg+

I think my walls are plasterboard with studs but I'm not 100% certain... If I can confirm, through drilling little test holes, that there are studs are either or both of the following options ok:

1) if studs align perfectly with tv mount then just drill into wooden studs and mount on them with 4 x corner holes of tv mount, then the 2 middle holes of tv mount use heavy duty gripit plasterboard fixings.

2) if studs don't align, or just anyway, use something like 18mm ply/mdf to span all available studs behind tv, fix that in with numerous screws into wooden studs, then screw tv mount into the ply. < If I use this option should I go all the way through wood and plasterboard with the tv mount fixings or not?

Help hugely appreciated. I just want to avoid having to cut out the whole wall and but battens or additional studs in then replastering because that is waaay outside of my experience level. Thanks

Answer 1

Your #2 idea to use some sheet material to span across the whole range of studs is the way to go. However do not use MDF or particle board. Both those materials have terrible screw retention problems. Instead use good quality plywood.

Also use thicker plywood if you can get it. 18mm thickness is a little on the thin side for this application. Try to get 20mm or more. The reason is that full motion TV mounts will put incredible stress on the mounting screws and you want to maximize the ability of the plywood to grip the screw threads and provide the maximal pull-out strength.

Note that when mounting the plywood to the wall always use a pilot drill of the appropriate size for the screw threads into the stud. Sized properly the installed screw will be stronger than if you try to just brute force it into the stud without the pilot hole. The same thing for the mount screws into the plywood - use pilot holes there too.

The size of the plywood sheet may want some consideration. If you can get substantial coverage over studs and still have it largely behind the TV than it will be easy to paint to same color as the wall and be hardly noticeable. On the other hand if it has to be larger than the TV then it may actually be aesthetically better looking to extend the plywood all across the width of the working surface.