How do I fix wall cabinets to thermalite blocks?

[dmt]

Hello!

I am in the process of moving our kitchen to an extension, built about twenty years ago, and I have discovered the interior walls are built with thermalite blocks. It is wonderful to drill into but I have concerns about securing wall cabinets to it! The cabinets will have to carry quite a bit of weight of crockery.

Any advice on the best type of fixing would be much appreciated.

DT

[Phil Anthropist]

I don't know, but Thermalite do give technical advice:

[dmt]

They do but it is a bit 'non commital'. Generally there advice is you can use "anything suitable".

[Phil Anthropist]

If there are no special fixings for Thermalite and it will take normal plastic wall plugs then all I can suggest is that in addition to using the usual wall cupboard brackets that you also fix one or two horizontal wooden battens to the wall with long screws and wall plugs well into the Thermalite. These battens will be behind the wall cupboard and you can screw through the back of the wall cupboard into the battens. The back of the cupboard may be hardboard therefore you will need to put some corner brackets level with the battens so that the battens are fixed to the sides of the cupboard. I have used this technique when both the usual cupboard brackets coincided with electric cables under the plaster and it was easier to use wall battens than to dig out the cables and re-route. You might also be able to reduce the weight to be supported by storing some of the heavier crockery in a base unit.

[zaax]

[Andrew Gabriel]

One particularly interesting comment in there...

"use a steel, not a masonry bit".

I never use hammer action, but I hadn't thought of using a steel bit in thermalite blocks.

[dmt]

Yes I noticed that bit and thought it a very worthwhile bit of advice. The secret with drilling into Thermalite seems to be keep the hole as small and as parallel as possible. I found this link

and I think I might go for the twist lock anchor.

[<F1LBY>]

Use Wickes nice grey rawl plugs - they&#39;re excellent. All my kitchen cupboards are hung of the wall with &#39;em (Thermalite behind the plaster). No casualties in the last 3 years and heavy objects in the cupboards. They adhere well to Thermalite with no slippage - and they don&#39;t fall apart either.

[salesguy]

...

Defo use a steel bit. The small &#39;wings&#39; on a masonry bit expand the hole & loosen the fixing.

The helix type of fixing are spot on - they will hold a cabinet + contents. If you are really worried, use a batten fixed with 4 of the helix fixings & then screw into that.

Also, drill the hole for the fixings 1mm smaller than specified. The fixings will still hammer in fine & they will be nice & snug.

SalesGuy (ex Thermalite salesman)

[dmt]

Sounds good to me! Thanks!

[dmt]

Well I investigated the range at Wickes and plumped for their &#39;Universal&#39; fittings (Screwfix also do them:

), complete with screws. The pack instructions said use an 8mm masonry bit but as per previous advice I used a 7mm steel bit. As it happened a 7.5mm bit would have been better as 10% of the plugs bent as they were hammered in, once they bend you may as well give up and try another. Apart from the minor issue though they went in superbly and are rock solid.

I did try a conventional, basic wall plug to compare and that was rubbish. I think I will use these universal fittings from now on, definitely worth the extra.