Scrub the tile with a mixture of 1 part white vinegar to 4 parts water or use a mild grease fighting dishwashing liquid and water.
Painting terracotta roof tiles.
Nutech elite terracotta primer has been specifically formulated to provide superior adhesion and long term performance over properly prepared unglazed glazed and vitrified terracotta roof tiles.
I am not sure that painting terracotta roof tile is the best idea.
Once the firing is complete these tiles will withstand years of weather exposure when professionals properly install them on a roof.
Also to mention that any product guarantee will be lost.
Apply masonry primer to the terracotta tiles.
Since terracotta tiles are.
Use a nylon scrub brush or sturdy mop.
How to paint on terracotta tiles step 1.
The pros and cons of painting terracotta roof tiles.
If painter claims they can paint a terracotta roof then ask for manufacturers data sheet and double check the product is suitable and guaranteed for terracotta coverage.
Clean the surface with a trisodium phosphate tsp cleaning solution and a rag.
I was doing research as i was getting mixed answers and learned that terracotta is very porous.
Painted or coated as an application such as this would have trouble with any mechanical adhesion.
Even if you paint the top of the tile moisture can be sucked in from underneath and cause the paint to flake off.
Any one promoting the re glazing sealing painting of terracotta roofing tiles should be avoided.
Protect nearby surfaces with painter s masking tape and plastic sheeting.
Terracotta roof tiles are created from clay and fired with a glaze to provide a long lasting protective finish that contains an attractive sheen.
Change all broken tiles.
Since you cannot paint terracotta roof tiles here is the terracotta restoration process.
Terracotta roof tiles which have glazing evident should not be sealed.