Poor Painting Surface

Sydney Painting
Grease, oil, or other contaminants will prevent paint from bonding well to a surface. Even the sebum from human skin will cause painting problems. In some cases the painting over grease or oil will simply result in an uneven looking paintjob. In other cases the oil or grease will completely prevent the paint from bonding to the surface. The paint will form bubbles or simply peel away.
House Interior painting
Most internal walls need moderate cleaning over the entire surface before painting. Grease is most likely to exist at arm height, where people touch the walls, and it is more common in houses with children. But the entire wall surface should be neatly cleaned as grease is often hard to see. Sugar soap or Trisodium Phosphate are the two most common cleaning solutions. These are mildly alkaline solutions (base, the opposite of acid) made form powder that will remove grease and oil that routine domestic cleaning products tend to leave behind. For most walls this is quite sufficient. Walls should be dusted / vacuumed before being cleaned with sugar soap / trisodium. 
Other Wall Painting.
If the interior walls are near any cooking facilities they will be exposed to fairly heavy grease and oil. This will accumulate over the years, often making the uncleaned surface impossible to paint. Walls near fireplaces, some heating appliances, many bathrooms, or rooms with crayon marks will cause similar problems. They may need thorough cleaning, at least in some areas.

Some stronger solvents for problems grease areas.

- Citrus cleaners like De-solv–it. This appears quite safe and works well for 99% of wall stains. 
- Acetone – probably the strongest solvent. Used in nail polish. Make sure the room is ventilated and avoid breathing acetone. 
- Turpentine – the basis for oil paint. This may remove paint as well as oil and grease. 
- Hand sanitizer will remove some wall marks, though the other cleaning methods above are probably more reliable. 
Door frame and Skirting board painting services Sydney
Door frames and window sills often have a lot of contact with human skin or other sources of grease. Even a thorough cleaning may prove insufficient to remove the grease and oil. Occasionally the surface must be sanded back and given an undercoat before painting. 
Commercial painting Sydney
Talk to your painters about surface preparation before painting. We all want the best results from painting.