Render removed and what to do now. All help appreciated

Help required please

I have had my kitchen plaster boarded (foil back boards) and skimmed due to old plaster bubbling and feeling wet. The plaster dried on three walls in a matter of days. Although the back wall was still not dry after 3 weeks. I spoke to a friend who suggested that I remove the rendering on the external part of this wall as when he tapped this it was hollow and may be holding water.

When I removed the render it did seam to be hollow in parts and it I also noticed this was not sealed at the top which I suspect was letting the rain water run down the wall and rest in the hollows. Since removing the render the plaster is drying but due to having no radiator in the kitchen it is taking longer than I would have hoped.

The problem I now have is that the external wall is in a poor stat as this used to have a door in. and has been bricked up but not to good and the pointing could do with being renewed. There is also a wooden lintel still in the brickwork which was for the door also. So if some knowledgeable person could advise me in what steps I need to take and in what order. Do I need to let the plaster dry out and then fix the pointing or do I fix the pointing first and do I put some sealer on the brick work first and if so what do I use?

I apologise for this question but this is my first house and just getting to grips with trying to fix problems myself as I have had my fingers burnt of to many rouge traders.

How did they fix the plasterboard to the inside of the external wall? If they used foil back plasterboard on battens the dampness in the wall shouldn't have much effect on the plasterboard. However if the p/b is just stuck to the inside of the wall, it could easily be getting cold so moisture in the air condenses on it. This could also happen if they used battens but to a lesser degree.
You'll need to repair the external wall properly - rake out loose mortar etc before filling to a reasonably flat surface for rendering. Once rendered, the core of the wall should get reasonably dry, but do you know whether you have a sound dpc at around ground level? It can be hard to stop rising damp in old buildings.
Photos would tell a thousand words....

Hi regsmyth

The plasterboards were just dot & dabbed to the existing wall as originally the walls were just going to get skimmed but as they felt damp and so uneven it was decided to put the p/b on in addition.

The only problem I have regarding re-rendering is that I thought this may have been the cause of the damp in the wall in the first place. Due to possibly bridging the damp proof cause I had done back in 2000. The old rendering left two bricks off the ground and I don’t know if that is the normal. If this is not the case then at what height should I put the new rendering as to not bridge the dpc?

I will also take some photos and post them later tonight.