Fitting bathroom cabinet into 2 layer plasterboard wall

kan_user

Hi,
We plan to fit a mirrored bathroom cabinet (~20 Kg) into a plasterboard wall. The wall seems to have 2 layers of plasterboard followed by some hard material which may be plywood (tried tapping a small drill bit to find whether its stud or not).. The screws provided with cabinet are 45mm long but only go 30 mm into wall due to 15mm depth of wooden collar in cabinet's back sheet.

When i tried screwing directly into plasterboard wall (with no fixings assuming plywood sheet after 2 layers of plasterboard), the screw didn't bite strong enough and cabinet was bit loose. I fear this may not work and cabinet will come down when i put mirror doors and fill up cabinet space. The screw holes in cabinet are not spaced at 40/60cm and aligning them to stud work is not feasible.

Do i need any fixings for a 2 layer plasterboard wall? Even if i use any fixings, do i need longer screws to reach hard material after 2 layers of plasterboard ?? Or is there any alternate way of putting up cabinet..

Regards,
Diy-er

Plumber90

If you think there is ply behind can't you use a longer screw?

kan_user

Plumber90 wrote: »

If you think there is ply behind can't you use a longer screw?

How do I check it's plywood for sure?

jc808

if its going to be behind a cabinet anyway, consider taking a section of PB out and that will tell you for sure whats behind.

Kiran

Try screwing a longer screw into one of your existing screw holes. If it bites then just use longer screws. If it doesn't then you'll need plasterboard fixings.

martinthebandit

Kiran wrote: »

Try screwing a longer screw into one of your existing screw holes. If it bites then just use longer screws. If it doesn't then you'll need plasterboard fixings.

Seems the sensible answer to me.

andyhop

Use some cavity fixings . Two layers of plasterboard will either be sound or fire board so will have strength to hold much more than your trying to hang. You want the fixings that compress and need a setting tool to fit

jc808

Looks interesting that setting tool - how do you use it?

kan_user

andyhop wrote: »

Use some cavity fixings . Two layers of plasterboard will either be sound or fire board so will have strength to hold much more than your trying to hang. You want the fixings that compress and need a setting tool to fit

Thanks for replying.. There is no cavity after 2 plasterboard layers. I tried screwing 45mm size directly into wall (without cabinet) and it wasn't too loose but not strong either. Maybe i need to try a longer screw instead..

PheoUK

Do you know what's in the wall? Pipes etc?