Which surfaces need colour?
For every surface there is a paint product that has been developed to last in the particular conditions where the paint is intended. For example, the kitchen and bathroom should be painted with a durable and washable paint (usually higher gloss level), but for the living room or bedroom ceiling it is quite sufficient to use a full matte colour that does not require cleaning. Also a colour that is meant for the interior is not strong enough to withstand in the outdoor conditions. By choosing the right colour product for the surface, it will look beautiful for a long time and you don’t have to re-paint every year.
Does the surface need priming?
Wood surfaces must be primed to ensure proper adhesion of the paint.
Knots in the wooden surface must be primed to prevent resin from flowing out.
Priming the walls and ceilings is especially important, if the surface is partly puttied. Without priming the surface will absorb the paint unevenly and as a result the surface might have uneven level of glossiness.
A weak stucco surface has to be primed with alkyd primer in order to make the surface stronger and to give the surface better coverage with the paint later on.
Priming may also be necessary when transitioning from one type of paint to another (for example painting oil pint over with latex paint).
The surface absorbs the primer well, and the primer evens the porosity of different surfaces. This ensures good coverage of the paint later on.
It’s not important for the primer itself to have great coverage, because the surface will be pained over with a finishing paint. Priming reduces the finishing paint consumption and ensures a lasting result.
What types of paints to use – Water-based or solvent-based?
It is certainly more convenient to paint with a water-based paint, which is low-odour, easily applied, dries quickly. Furthermore, you can clean your painting tools with just water. Today, water-based products are offered for almost all types of interior surfaces.
However, solvent-based paints also have their advantages. They are well absorbed by the surface, where the form a washable, durable and even coat of paint. Thixotropic alkyd paints are available, that do not drip or flow. Solvent-based paints are most commonly used on metal and wooden surfaces (windows, doors, furniture).
With previously painted surfaces it is best to re-paint with the same type of paint. With a new surface, determine the right type of paint by:
- the appearance of the surface with the particular type of paint (colour samples at the store)
- the level of glossiness (solvent-based paints are usually more glossy)
- the selection of different colours and tones
- the price
What gloss level to choose?
First, decide whether you prefer a glossy surface or a matte surface. Paints generally have 6 different levels of glossiness, which are indicated on the product package:
- Full glossy 90-100
- Glossy 60-89
- Semi-Gloss 30 to 59
- Semi-Matte 11-29
- Matte 6-10
- Full matte 0-5
The general rule is that the glossier the paint, the stronger the coat of paint is. This means that a glossy paint does not get dirty so easily and it is also more durable and washable. It is also important to know that a glossy colour brings out the smallest roughness’s the surface may have.
Full matte paints is usually washable and are therefore best suited to dry rooms. Innovative raw materials also allow exceptions where a matte exterior paint is also weatherproof.
The glossier the surface, the deeper and more vivid the colour we perceive. The porosity of the painted surface greatly affects the way we perceive the colour. If we compare the same tone of colour with one being glossy ant the other being matte, then you can easily see that one is darker (glossy) and the other is lighter (matte). This is due to the fact that a stronger and even surface reflects the light quite evenly in one direction which makes us see the colour deeper and darker. From a more porous surface that light reflects in more different directions and we perceive it as being lighter. The binder of the paint also affects how we perceive the colour. With acrylate paint colours seem more blue when with alkyd paint the colours seem more yellow.
Useful suggestions for painting
1. Plan your work carefully
Calculate how much paint is needed, purchase necessary equipment and supplies for painting. Make a plan where to start painting and how to finish your task. Check the tone of the colour on a small surface before painting the entire room.
2. Painting conditions
The temperature of the surface, the paint and the air must be at least +5 ° C and the relative humidity of the air should be below 80%. All surfaces must be clean and dry. If you are using solvent-based paint make sure the room is adequately ventilated, but do not cause a draft. In a very dry and warm room the paint will dry too quickly and the painted surface will be uneven.
3. Use protective equipment
Use suitable work clothing and other protective equipment. Use a dust mask when sanding, which effectively protects the respiratory system from inhalation of dust. When sanding a puttied surface, use protective glasses.
4. Putty carefully
The more precisely you putty, the less sanding is needed and the consumption of putty is also reduced. Note that you usually have to putty twice, because the putty shrinks when it dries.
5. Tools for puttying and sanding
For puttying use a steel filling knife with a width of 100-600 mm depending on the size and unevenness of the surface. For sanding use a sanding block or a base plate hand sander, for larger surfaces you can use a base plate sander with a telescope handle.
6. Priming is important
Priming is especially important with partly puttied surfaces, because surfaces with different porosity absorb the paint differently. The primer forms a base surface that absorbs the paint evenly and ensures better adhesion.
7. Use high-quality tools
Despite the higher price it’s always worth to use high quality equipment. High-quality paint rollers absorb the paint better, don’t leave hairs on the surface and the coat of paint will be even.
8. Use masking tape
Cover the surfaces that your do not want to paint with a plastic to protect them from paint splashes. Attach the plastic with a masking tape. Remove the tape immediately after painting, because later the dried paint may come off with the masking tape.
9. Make sure the painted surface is clean
The workplace should be cleaned from dust, because, for example, latex paints will not stick on a dusty surface and dust that attaches on the freshly painted surface will ruin your work.
10. Start painting from the ceiling
Always start painting from the ceiling. This will prevent paint splashes on finished walls and floor surfaces. Paint in the direction of the light in order to reduce the visible traces of the paint roller. Use plenty of paint to extend the drying period of the paint which allows it to dry evenly. Read the instructions on the paint package before you start painting.
11. Clean the painting tools
During breaks from painting, put the paint roller in a plastic bag and the paintbrush in a jar with suitable thinner. Clean the tools right after you have finished painting, this way you can use them next time as well. Follow instruction on the paint package on how to remove left over paint from the roller and brush.
12. Think about the environment
Do not pour the paint or thinner down the drain, into a lake, river or other body of water nor into the soil. Not even when the paint is water-based. The additives in the paint complicate the cleaning process of the water in cleaning stations. Liquid paint residues should be taken to a collection point of harmful substances or you can let the paint dry and take it to the dumping ground along with empty paint cans.