How to calculate how much paint to buy?

[MWP]

I need to paint my daughter's studio apartment and wondering how much paint I will need, along with other pieces of equipment. The studio is a combined living room/bedroom 4.2mX4.3m (a large built-in wardrobe takes up half of one wall and sliding glass doors take up one other end of room) and there is a narrow hallway 2.6m long.

I believe there are paints which include primer, instead of doing a primer coat first, is this a good idea.

Many thanks

Michael

[MitchellMc]

Hi @MWP,

As a general rule, paint coverage is typically around 8m² per litre for two coats, depending on the surface and the paint you're using. Given the size of the room and hallway, and factoring in the wardrobe and glass doors, you’re likely to need around 6 to 8 litres of paint for two coats on the walls. That assumes standard ceiling height and that you're just painting the walls.

If the current paint is in good condition and is low-sheen, then priming is not required. Clean the walls with Sugar Soap and then wipe them down with fresh water. Once dry, you can then coat the walls with something like Dulux Wash and Wear. However, if the existing paint is glossy, patchy, or you're covering a dark colour with a light one, a separate primer would be worth considering. 

Please let me know if you have any questions.

Mitchell