How to hang wall cabinet with void behind plasterboard?

[subzero]

Hoping for some advice hanging kitchen wall units.

We have a plasterboard stud wall, behind which is blockwork (extension newly built). So far we've mounted one wall unit by drilling straight thru the plasterboard and into the blockwork. The plasterboard in this area is almost flush mounted onto the blockwork, so there is no void/cavity behind. We are using 50mm wall plugs, pushed thru the hole in the plasterboard so that the 'head' of the plug is flush with the surface of the blockwork behind, in order to form a secure mounting. The screws are domed head 60mm. We are using these fittings after taking advice from a major hardware store, and this first unit seems to be secure.

The problem we now have is that the 2nd wall unit needs to be mounted on an area of wall where there is actually quite a void (90mm) between the back of the plasterboard and the surface of the blockwork.

We are thinking that the correct approach should be to use an extra long drill bit, and drill thru into the blockwork as above using the same type of plug for the blockwork, but with the addition of a 2nd plug for the plasterboard. Then use a much longer screw to secure the mounting all the way thru. However, we do have our doubts as to the strength of this fixing especially with the stress on such a long screw, but there doesn't seem to be an alternative.

Would be very grateful for some help with this problem.

Thanks in advance

 

[foxhole]

Cut out strip of plaster board at top of cup'd line and install a 90mm thick timber to wall, then you can screw straight to timber.

 

[subzero]

Thanks for the reply - we may have to do that

However just been to the local diy shop and explained the issue and they suggested using a 10mm expanding Rosette fixing which is new to me. Supports up to 38kg on the plasterboard, you just tighten until the 'rosette' expands behind the plasterboard forming a very strong fixing.

Any experience of using these?

 

[maltaron]

I would go with foxholes suggestion. Any fixings to the plasterboard will only be as strong as the plasterboard and I would not like a cupboard hanging on it.

 

[foxhole]

Fully laden kitchen cup'd could weight far more than that.

 

[subzero]

Foxhole,

Have tried your suggestion in cutting away a section of plasterboard but have found the following.

On the left hand side securing position (i.e. top left bracket position for the wall unit), there is pipework in the void behind. This is flush to the brickwork, at a depth of about 5cm. There is also an electric cable in this area.

Immediately to the left of the securing position, there are four layers of plasterboard going back towards the brickwork. So it doesn't appear that there is anywhere we can secure a wooden baton.

The design of the the kitchen is such that the wall units cannot be moved from their designated position. We have to resolve this somehow.

What can we do?

 

[gregers]

pack out with timber battens as best you can then screw(safly)ply onto the battens.

 

[foxhole]

Foxhole,

Have tried your suggestion in cutting away a section of plasterboard but have found the following.

On the left hand side securing position (i.e. top left bracket position for the wall unit), there is pipework in the void behind. This is flush to the brickwork, at a depth of about 5cm. There is also an electric cable in this area.

Immediately to the left of the securing position, there are four layers of plasterboard going back towards the brickwork. So it doesn't appear that there is anywhere we can secure a wooden baton.

The design of the the kitchen is such that the wall units cannot be moved from their designated position. We have to resolve this somehow.

What can we do?

Cut timber around any obstacles and secure where you can, you could then use a wall rail to replace the supplied hanging brackets , this spreads the load so you don't have to mount individual brackets in awkward places.[You should be able to cut away the four layers on plasterboard with relative ease.]

http://www.catchesandlatches.co.uk/details.php?product=1796

 

[subzero]

Thanks again for the replies, we've managed to figure out how we can securely attach a section of timber to provide a support batten.

There is a vertical stud halfway along the width of where the wall unit is going, which the batten can be secured onto, plus a fixing point into solid brick and another fixing point into another vertical stud on the leftmost side.

We then plan to attach the rightmost bracket to the timber. On the left side where it's difficult to install a noggin of any kind, we will go with a Rosett fixing plus another central bracket fixing thru the batten and into the vertical stud. Hope this makes sense. Have taken some pics so will try and upload those.

It certainly takes away some of the mystery/worry when you can actually see what you're dealing with behind the plasterboard when a section is cut out.

The hanging rail approach also looks good, hadn't thought about that one.