So, you’ve found your way here because you’ve installed insulated plasterboard and you want to fix something heavy, like a TV, to your walls.
Lightweight mirrors or lamps? Fine. Just use a self-drilling drywall anchor fixing, which is usually OK for loads of up to 8kg.
Medium weight shelves or cabinets? Also fine, but be sure to use steel expanding cavity fixings, or ‘umbrella’ fixings, which transfer the load (of up to about 12kg per fixing) behind the plasterboard so that the stress is put on to a wider area.
But heavyweight items? Well, we hate to be the bearers of bad news, but you can’t actually fix heavy items directly to insulated plasterboard – it simply wouldn’t take the load.
So, what are you going to do about your far-too-expensive wall-mounted TV? Or that antique dresser that’s screwed to the wall to stop it falling on any heads?
Well don’t worry, we have a couple of solutions – you don’t have to start eBaying just yet…!
With heavier loads, you don’t fix to insulated plasterboard, but through it.
But wait, before you start banging holes in walls it’s important to consider how your insulated plasterboard has been installed.
If it has been installed via plaster dab or drywall adhesive directly to the masonry behind, your only real option is to use anchor fixings to attach the fixture into the masonry itself.
Alternatively, it might have been mechanically fixed to timber frame studwork, metal furrings or to pre-treated timber battens that have been backed with a strip of damp proof course and fixed to a masonry wall. Here you can attach the fixture to the timber behind – whether this be the studs or noggins of a timber frame construction, or timber battens that have been fixed on top of the masonry. In this instance you would use self-tapping wood screws.
Another option in this latter instance is to is to fix a plywood sheet in the area between the timber battens where the fixture will be located. The fixture can then be attached to the plywood sheet using ‘umbrella’ fixings.
While this method requires some thinking ahead, as you will have to decide where to place your fixtures before installing the plasterboard in the first place, it will save a lot of the time and hassle as it gives you a larger area in which to fix, rather than wasting time trying to find a noggin or batten.
However, please bear in mind the following when using this method:
- This plywood sheet must be a minimum of 18mm.
- The plywood sheet must be supported behind by pre-treated timber support battens.
- You will probably require a deeper batten than the usually recommended 25mm in order to accommodate the depth of the plywood and also the timber support battens.
- The plywood sheet should fit flush to the surface of the timber battens to which the insulated plasterboard will be fixed.