Exploding Cornice?

[Metal Head]

Now I have got your attention . I have attached 3 photos of some cornicing that was put up in our kitchin by Harvey Norman 3 months ago when they put in a new kitchen. It appears the nail(s) are moving out and have caused the local plaster to break.

As well as this, a crack has formed on one of the joints and it moving away from the plasterboard.

Can this happen in such a small space of time or is it just bad workmanship?.

All replies will be much appreciated.

Cheers
MH

[ozwinner]

Looks like the cupboards are moving or shrinking a bit.

Al

[rod@plasterbrok]

Hi Metal head.

What you have there is not uncommon around a kitchen cupboard.

The has been some obvious movement in the cupboards to cause the type of damage around the nail.

It appears to me that whoever installed the cornice has done the correct thing by nailing/screwing as well as the cornice adhesive. Movement in the cupboard bulkhead is the cause of the cracking, I would address this before an effective repair can be done. Without seeing the structure it is hard to recommend a way to fix the bulkhead.

There can be other causes such as flex in a truss roof or floor movement if its a 2 storey home, etc. When you repair the cornice use a flexible sealant to the under side of the cornice where is abutts the timber bulkhead.

Plaster will not adhere to the MDF bulkhead and will form a hairline crack underneath. (this is only a part of the problem you have here).

I use a different method of cornicing around a cupboard bulkhead that does not require screws or nails, that allows for slight movement in the cupboards.

The main objective is to attach the cornice in such a way that it won't fall down and allows for very slight movement in the cupboards. When you fix with a nail or screw and there is movement the nail or screw will always pop or in the worst case break away the cornice underneath as you have there.

By fixing the cornice the way shown in the pic (rushed drawing) you have no nails to pop and very solid fixing, that also helps keep the bulkhead solid. You also need to use cornice adhesive on the edge of the mitres to lock them together, rather than just filling the gap.

Hmm it won't let me attach the pic comes up with error on page. I will post this, then put the pic in another post below

Cheers Rod

[rod@plasterbrok]

Here is the pic I hope. In addition to the above information. If you cant put a temporary nail in due to damge to a pre-finished bulk head, use screws through the cornice but remove them after the cornice cement has set. Then patch where the screw holes were.

Leaving the screws in, can lead to the problem Metal head has.

Caution though:
Only remove the screws if you have applied adhesive as described in the pic. If you use the standard method of applying adhesive, you will need to leave the screw in place.

[China]

Only 3 months I would be contacting Harvey Norman what ever the cause