Janice (a.k.a The DIY Diva) has been writing décor and DIY articles for the past 6 years. Read more
The paint of the interior wall of my lounge, just on one side at the lower half, is blistering and peeling (and the plaster underneath is 'crumbly') - I'm assuming it's due to the damp.
The problem could be caused by deterioration on the DPC (damp-proofing course), which could result in ongoing problems. It could also be that the outside level is higher than the DPC on the exterior in that particular section.
I would suggest that you remove as much paint and crumbly plaster as you can. Then use a product such as Coprox to apply to the substrate surface before applying new mortar and repainting.
If the problem does come back you may have to remove a larger area and treat with Coprox. I've used this product myself so I know that it works extremely well - even after 5 years.
For more information on damp, moisture problems and re-applying mortar to walls, visit: www.Home-Dzine.co.za - DIY and Maintenance.