Instructions: Paint the garage door correctly

Heat, cold, snow and hail all leave their mark on garage doors over the years. In addition, there are many a push or kick. All of this has a lasting effect on the texture of the surface. The consequences are scratches, rust spots and peeling paint. At least now it's time for a new coat of paint.

The trade offers a diverse selection of different materials for garage doors. These can be made of steel, stainless steel, wood or aluminium. Galvanized gates are also not uncommon. Depending on the material, the surfaces are prepared differently for painting.

Paint galvanized garage door

In general, preparation is one of the most important prerequisites for successfully painting the garage door. In the case of galvanized garage doors, dust and dirt are removed from the surface using zinc cleaner, ammonia solution (ammonia solution) and a little washing-up liquid. For this purpose, the surface is treated with an abrasive fleece until a fine, mostly gray foam forms. Protective gloves should be worn during this preparation. After ten minutes exposure time, the surface is rinsed off with clear water and the old paint that has flaked off is removed with a spatula. The surface is then only lightly sanded with a sanding machine.

After the preparations are complete, the galvanized garage door can be primed. A special zinc paint is chosen for this purpose. After drying, the garage door is painted with the appropriate paint. The best way to paint the narrow gaps is with a round brush. A foam roller is used to work the surfaces. In this way, consistent results are achieved.

Paint steel garage door

Even a metal garage door needs to be well prepared for painting. The following work steps are necessary for this:

• First, all dust and dirt such as grease residue and salt deposits are removed.
• Use a wire brush and sandpaper to remove loose old paint from the door surface.
• If these cannot be removed, the surface should be sanded down as much as possible.
• Then degrease and clean the surface with a metal cleaner.
• Treat spots of rust with rust blocker.
• Slightly roughen very smooth surfaces with sandpaper.

After the primer has hardened, sand the surface again with sandpaper. A suitable colored paint for painting is now applied according to the metal. As a rule, water-thinned acrylic paints are applied in two steps. A layer of transparent top coat is applied to these two layers. This should be high-gloss or at least semi-matt.

Painting wooden garage door

Wooden garage doors are very trendy because they give the property a very unusual charm. Mahogany, merbau and red cedar are among the most popular types of solid wood for garage doors. Nevertheless, thorough preparation is essential and very time-consuming, even with wooden door surfaces.

• First of all, the old coat of paint has to be removed completely, because the new paint will not stick to dissolved paint particles.
• Simply remove the coarse paint and varnish residues with the brush.
• Sandpaper with the appropriate grain size or the use of a sanding machine is suitable for fine work.
• The narrow gaps are stripped with handy grinding tools.
• In the last step, thoroughly remove the sanding dust.

After the preparation, the primer follows as the first coat of paint. It is painted with an acrylic wood insulation. With regard to the drying time, the manufacturer's instructions must be observed. A suitable wood stain can then be applied. Finally, the last coat is applied with an appropriate protective varnish.

Painting aluminum garage door

In order to paint an aluminum garage door, it must be specially prepared. In addition, it is strongly advisable to only use products that are specifically designed for the non-ferrous metal.

• Since aluminum is known to form an oxide layer on the surface, paint and varnish adhere only with difficulty. As a result, this layer must be completely removed before the aluminum gate gets a new coat of paint.
• The surface should be sanded with fine sandpaper (120 grit) and sanding fleece.
• Carefully remove adhesive silicone and grease residues. Either with thinner or with a special cleaner.
• Then let it dry completely.
• Shortly before priming, the surface is wiped again with a duster.

An adhesion promoter is applied as a primer. Depending on the manufacturer's instructions, the drying time must be observed. After priming, painting takes place in two work steps. First, a base coat (water-based paint system) is applied. Before the top coat can be painted, the base coat must dry according to the manufacturer's instructions. The top coat serves as a seal and protects the aluminum door from the weather.

Paint garage door made of plastic

Sometimes garage doors are made of plastic. If certain aspects are taken into account, these can also be painted. However, before the plastic gates can be painted, they must be cleaned of any dirt and other contaminants. To do this, wipe the surface with a damp cloth. A few splashes of washing-up liquid in the cleaning water help against stubborn stains. Plastic garage doors should not be sanded before painting, as this will cause unsightly scratches on the surface. Light sanding is recommended.

Plastic-coated garage doors can then be painted or sprayed with the appropriate color. When spraying, the paint is first sprayed onto a piece of newspaper and then, without stopping, sprayed onto the surface from a distance of 30 cm. In this way, unsightly drops can be avoided. After drying, check for unevenness and, if necessary, treat the surface again with the paint spray.

Worth knowing about painting garage doors in brief

• A wooden garage door is very different to paint than a metal one.
• The following applies to both: It is best to paint when the outside temperature is around 20 °C so that the paint retains a good consistency and dries quickly.

Metal garage door

• In general, there is a large selection of different paints to work with.
• There is a choice between special paints for garage doors, but normal metal paint can also be used.
• The advantage of garage door paint is that it can be painted directly onto zinc, while other paints require a primer.
• Thorough cleaning of the garage door before painting is particularly important. Old paint must be properly removed with sandpaper.
• Grease and salt deposits as well as other dirt must be carefully removed with appropriate cleaning agents.
• The surface is then cleaned and degreased with a special metal cleaner.
• Rusted areas should be rubbed with a rust blocker so that the rust cannot eat through the new garage door paint.
• Important when painting with a flat brush: It must be painted evenly from top to bottom.
• The first coat should then have around 2 hours to dry before the second coat of paint is applied.
• It may happen that, depending on the paint, a third coat is required.
• Between the application of the different layers, brushes and, if necessary, be washed out thoroughly.

Wooden garage door

• When repainting the wooden garage door, as with the metal door, the old substrate must first be thoroughly removed.
• The old coat of paint can be roughly removed again with a wire brush and sandpaper.
• The remaining paint can be sanded off with a machine (or manually).
• The brush attachment of a drill can be used for the narrow spaces between the joints.
• When the old varnish is removed, a coat of acrylic wood insulating primer is applied.
• It is also recommended to finally treat the garage door with window and door glaze, as thick layers of glaze are more durable than thin layers.
• Of course, normal wood preservative glaze can also be used.

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