lime over gypsum plasterboard?

[christianb]

Lime plaster will not adhere to plasterboard

I refer the honourable gentleman to my previous answer. Drill holes in the board and it will stick. I've done it several times with no failures.

 

[BMcD]

christianb wrote:

I refer the honourable gentleman to my previous answer. Drill holes in the board and it will stick. I've done it several times with no failures.

I'm not doubting your success using this method, only I wouldn't adocate using it because:

• A. Drilling a gridwork of holes at 100mm centres in plasterboard will compromise its integrity
  
  B. You still have large areas of plasterboard between the holes which lime plaster will not adhere to.
  
  C. Although plasterboard is a low suction background, the core is excessively high in suction and will dry out the plaster as it is squeezed through the holes to form the nibs. The plaster will be weak at these points as it will not achieve its full strength due to rapid drying caused by the excessive suction.