www.ultimatehandyman.co.uk

Hi All,

Fairly basic/newbie question.

Do I need to apply a stain blocker before painting to the marks shown on wall in the photo attached. They were present after removing furniture, so presume were caused by poor air circulation? (Not sure what the exact name/cause of the marks are). Tia

It could be just be surface damp and dried out. Wash it over first and when dry rub over with dull sandpaper to flatten it off. You could go over with a Zinsser sealer coat https://www.toolstation.com/zinsser-cov ... int/p56164 if you want to be sure but that looks like emulsion would go over. I am not there though.

DWD