Guide written by:
John, DIYer & IT developer, Brighton
Wall and ceiling paints come in a range of colours and finishes - matt, satin, gloss. Oil-based, acrylic or alkyd, wall and ceiling paints may be one- or two-coat and may be applied on top of an undercoat. Basic matte white or high finish satin, you choose!
What are wall and ceiling paints made up of?
Wall and ceiling paints consist of resins or binding agents, pigments, fillers, solvents and additives.
Resins or binding agents add texture to the paint and set in contact with the air. They ensure adhesion to the painted surface, the cohesion of other components and a durable finish. Basically, they bind!
Pigments are the particles that give the paint its colour, not actually dissolved in the paint but floating in suspension.
Fillers bulk out the paint, either to add specific properties or for economic reasons.
Solvents keep the binding agents in solution, hence ensuring the paint stays liquid. A paint's drying time depends on the nature of its solvents; additional solvent (e.g. white spirit) may be mixed into the paint. Solvents may be flammable.
Additives are compounds which give additional properties such as penetration into thesubstrate, improved adhesion, improved surface tautness or anti-mould treatment.
Wall and ceiling
Wall and ceiling paint: what's oil-based paint?
Oil-based (or glycerophthalic) paints
Oil-based paints are diluted and cleaned with a white spirit-type solvent. They offer strong opacity, very good surface tautness and are highly durable to boot!
These days, however, oil-based paints are giving way to acrylic and alkyd paints because of their high volatile solvent content. Their application requires good ventilation of the room both during and afterwards.
Consider using respiratory protection when applying oil-based house paint.
Wall and ceiling paint: what's acrylic paint?
Acrylic or water-based paint
Acrylic paints are the most common type of water-based paints.
In their favour: a reduced level of solvents and a considerably shorter drying time - 30 minutes to touch-dry.
The most environmentally friendly acrylic paints are awarded the European Ecolabel certifying low VOC (volatile organic compounds)emissions.
Your brushes and rollers can be cleaned with water - highly convenient and non-polluting. Acrylic paints can be applied in every room of the house.
Wall and ceiling paint: what's alkyd paint?
To understand where alkyds fit in, let's, first of all, compare the different types of paint we've already seen.
Acrylic paints don't give the same taut finish as oil-based paints - which are themselves problematic because they require the use of solvents and have a high VOC content.
Alkyd paints offer the best of both worlds: cleaning with water, short drying times, and impressive tautness - letting you create a lacquered or glossy effect and giving increaseddurability.
Alkyd paints are also less toxic and have a lower VOC emission rate than the oil-based alternatives.
Wall and ceiling paint: gloss, matt or satin finish?
Choosing the right finish for your wall and ceiling paint is as much an aesthetic as a technical question. Choose between three main types of finish: matt, glossy or satin.
Matte paints are the most fragile. Since they reflect little light, however, they hideflaws particularly well. Matte is an excellent choice for an old ceiling whose dinches and dings would be too visible with more light reflection.
For repainting walls, use satin paints for their increased durability. A satin finish will work in every room of the house and gives an attractive silkyappearance.
Gloss paints are even more durable and are recommended for door frames and woodwork. Gloss gives a more spacious appearance to small rooms and brightens darker spaces. A gloss finish will, however, reveal flaws in the painted surface.
Wall and ceiling paint
Wall and ceiling paint: what's a VOC?
VOCs, or volatile organic compounds, are chemicals present in paints that readily diffuse into the surrounding air when the paint is applied.
These products are thought to betoxic and carcinogenic, so avoid using paints with a high VOC content.
Paints are classified from A+ - for the lowest VOC content - to C for the highest.
In any case, you should keep the space well ventilated during and after application of paint and always wear a protective mask.
Wall and ceiling paint: what's an undercoat?
Undercoat: a definition
An undercoat is a specific type of paint. It's designed to prepare the ground for evening the surface to be painted and filling in the pores. Although you don't directly see it, the undercoat affects the final finish and must be chosen according to the surface being painted (the substrate).
Type of undercoat
An undercoat should be chosen according to the surface in question and can be:
- Universal for plaster, concrete or wood;
- Specialised undercoat to protect plasterboard;
- Hardener to strengthen fragile or friable substrates;
- Bonding primer, specific to contexts where bonding with the substrate is required.
Why choose a special single-coat ceiling paint?
Ceilings are substrates with quite specific properties, unlikely to receive shocks but liable to crack with age. Working at height is impractical and tiring, making a single-coat paint a good solution for quick yet slick results!
You can get paints which have a colour marker that disappears when dry.
The colour marker gives you a clear idea of where you've already painted so you don't miss a bit out - especially useful if you're repainting in the same colour.
Bear in mind that a mattappearancehides defects while gloss gives improved light diffusion and enlarges your room.
What quality of paint to choose for your walls and ceilings?
There's paint and there's paint - they're not all are the same quality.
While it's true you can get hold of basic stuff for a few pounds a litre, you might have to fork out a bit more for good quality paint. You start to see a really obvious difference when you triple the price per litre!
Good quality in a paint means improved adhesion to thesubstrate, reduced VOC emissions and better coverage for hiding the dings and unevenness in a surface.
Basically, if you're on your fourth coat of white and you can still see the old paint underneath, change brand!
Wall and ceiling paint: how many coats and how many litres will I need?
Number of coats
Most paints require two coats with drying time in between. There are single-coat paints that just need the one, as the name suggests. Be careful, however - the more porous the surface, the more coats you'll need, even for so-called "single-coat" paints.
The necessary number of coats comes down to the paint's covering power. If you want to repaint a black wall in white and you don't have a seriously powerful paint, good luck to you!
Number of litres
Easy - just refer to the manufacturer’s recommendations. A litre/area ratio is always given.
Paint is available in a range of pot sizes, from 0.5L to 10L. Buy exactly the quantity you think you'll need, allowing a little extra. Note that the price per litre goes down the larger you go, and the values given on the pot are for optimum application - add say 15% to be safe!
A final tip for choosing
In recent years, many unusual products have appeared. You can readily find specialised blackboard paint and even magnetic paint to turn a flat surface into a handy noticeboard. Colour ranges have been hugely expanded, with colour charts full of whimsical names. It's up to you to decide if you prefer "Sahara" or "Sand Dune"!
Concerning finish, matte paints are a bad choice for high-wear surfaces.
On the maintenance side, all paints give a washable surface but to varying degrees.
Keep an eye on VOC emissions and remember that proper preparation is essential to get the great results you're hoping for. Make sure you've got decent painting tools (tray, roller, overalls, dustsheets etc.) to give yourself a strong start - and hopefully finish!
Guide written by:
John, DIYer & IT developer, Brighton, 70 guides
Since I was a child, I was always interested in manual and technical works. Always fascinated by woodworking, I took advantage of my first flat as a playground. On the cards: electricity (of course, safety first!) and some partition walls; but also decorating with the help of the missus, made-to-measure furniture and little tricks to optimise the space, all the while remaining as original as possible. When the little one arrived, I started building bits and pieces for him! Lacking space, I have not got a permanent workshop and certain tools I dream about but are not part of my collection. Not to worry, I already know a lot about DIY and I have a high-tech profile that I hope will guide you in your decisions!