How to glue foam to metal: what you need and a review of popular brands

It is much more difficult to securely attach foam to metal surfaces than to ordinary walls

Don't know how to glue foam to metal? I have repeatedly asked myself this question, tried several options and now I want to share my own skills and tell you how to choose a high-quality composition, prepare the surface and glue the insulation.

When insulating garage doors, you need to attach the foam especially carefully, since the structure is exposed to temperature changes

What you will need

Pre-prepared:

measuring device (tape tape), knife, spatulas;
rubber (or cloth) gloves, burlap or clean rags;
degreaser;
grinding machine (for cleaning metal surfaces);
adhesive composition;
wooden support or plywood sheet for the foam board.

When using spray adhesive or foam, you should also stock up on cleaning fluid.

Preparatory work before installation

If you are thinking about how to glue polystyrene foam to metal with polyurethane foam, then it is important to know that this material can be fixed to almost any metal. Among other things, you can use almost any glue or putty. However, you cannot purchase a composition whose ingredients contain gasoline, acetone or any other solvent. The slabs will collapse.

Another mistake that craftsmen often make is not using enough adhesive. Such compounds must be applied to the back side of the slabs; this must be done in 5 places or more. First, the mixture is applied in the corners, and then in the center. Before gluing foam plastic to metal, you need to remember that saving is inappropriate here. To do this, some apply the composition only in three points; this is incorrect and violates the technology.

Before gluing metal and foam plastic, the surface should be prepared; it should be cleaned of dust, old paint and varnish coatings, dirt and rust. You can use an oscillating or belt sander for this. After such cleaning, the base is degreased with any convenient means. Gluing is not such a quick process; sometimes it is necessary to ensure that the material is fixed until the glue hardens. At first, the thermal insulation may slide under its own weight, so it must be supported from below with a board or plywood.

What glue is suitable

The fixation composition should not include acetone, gasoline or other solvents. They provoke the destruction of polystyrene foam sheets.

Polyurethane foam

The advantages include:

ease of use: a craftsman who does not have installation skills can work with foam;
low cost of the composition;
Foam is sold in cans, so it is used not only for gluing foam plastic, but also for sealing joints between slabs.

Disadvantages: the product glues any materials, but does not tolerate slowness. The foam dries quickly in the tube, so you will need a special solvent.

Polyurethane

Advantages:

synthetic glue is easy to apply;
has greater resistance to moisture than dry mixtures;
frost-resistant;
guarantees high adhesion;
moderate consumption of the composition (1 cylinder is enough for 10 m2).

The only negative is that to use the aerosol glue you will need a mounting gun.

Liquid Nails

They are not considered a reliable means, so for strong fixation they are used in conjunction with a dry adhesive mixture. Surface application proportions:

1/3 – liquid nails;
2/3 – dry mixture.

Is it advisable to use foam?

With the help of foam, you can simplify and speed up working with foam several times over. It is perfect for those cases when you need to do everything quickly and efficiently. It features high technical characteristics and low consumption. Sold in cylinders, making it easy to transport and use. Compared to simple dry mixtures, it is more expensive, but it pays off, because... 1 cylinder is enough for an average of 20-25 square meters.

The main advantage over aerosol adhesives is that you do not need to use water, electricity or any special equipment to work with foam. During the insulation process, it is possible to save up to 50% of time compared to other popular compounds.

There is no need to take technical breaks, there is no need to install a layer of reinforcement or drive in dowels, you can work even in cold weather. The foam is characterized by excellent adhesion to polystyrene foam. Resistant to fire and high humidity. Does not support combustion and does not emit substances harmful to human health.

Review of popular brands

The adhesive composition used for gluing polystyrene foam sheets to metal must be characterized by:

endurance to decrease in temperature;
possibility of use for outdoor work;
absence of any solvents in the product;
guaranteed high degree of adhesion of bonded surfaces;
ease of use.

It is preferable to choose a composition that contains composite mixtures, bitumen or plasticizers.

"Ceresit"

Due to their high quality, the brand’s products are respected by professional builders. Advantages of the adhesive composition "Ceresit":

Ideally applied to foam blocks;
good ductility;
can be used for interior and exterior work, resistant to temperature changes and various atmospheric phenomena;
impact-resistant, vapor-permeable composition;
environmentally friendly;
long period of adjustment (20-25 min.).

Disadvantage: The working solution must be used within 2 hours.

"Moment"

The Moment glue line is expanding every year. Positive properties of the composition:

even with prolonged use, the adhesive seam does not crack;
has excellent technical characteristics;
does not shrink or deform when dried;
frost resistance, water resistance, heat resistance;
the adhesive is available in containers of different volumes;
short drying period.

The disadvantages include the unpleasant odor of the glue (disappears only after complete drying), and is more often subject to counterfeiting (as a result of which the composition contains toxic components that are harmful to health).

"Master Termol"

Combined adhesive for polystyrene foam “Master Termol” has the following properties:

long period of adjustment of slabs (up to 50 minutes);
high adhesion and ductility;
the composition is environmentally friendly;
the lowest temperature for using the mixture is -5 ˚С, which allows installation work to begin earlier and finish later;
the technological movement time is 12 hours, after which the foam can be doweled.

Time to use the finished composition is 30 minutes, material consumption per 1 m2 is 6 kg.

"Profline 3K-45"

An adhesive mixture for installing foam plastic and mineral wool, which is suitable for interior and exterior decoration. Positive properties of the composition:

ease of use;
moisture resistance, elasticity, frost resistance;
economy;
high adhesion;
Shelf life of the finished mixture is 2 hours;
environmentally friendly product.

During preparation of the composition, preventive safety measures should be observed. The dry mixture is characterized by increased dust formation, so it is necessary to protect the eyes and respiratory tract from it.

"Penoplex Fastfix"

Highly effective composition for installation of thermal insulation. Advantages of glue:

universal - glues foam equally well to various surfaces, including metal;
ease of use - time for preparing the adhesive is reduced;
heat resistance – not afraid of temperature differences from -50 to +90 ˚С;
after the glue hardens, thermal conductivity is not impaired;
no shrinkage.

Those who have used Penoplex Fastfix adhesive consider the disadvantages to be the fact that the amount of work performed to cover the surface does not correspond to what is mentioned on the packaging; it is much less.

How to prepare the surface

No matter what adhesive is used, the preparation process is always the same. If the metal is not properly processed, then no glue will provide reliable fastening of the foam.

Materials and tools for work:

Metal brush . Used to clean the surface and remove rust and old paint residues. Instead of a hand tool, you can use a power tool - a drill or grinder with a special metal brush;

A special wire brush will help you quickly remove rust and paint from the metal surface.

Paint remover . It is used if there are several layers of old paint on the surface, which does not adhere very well and may peel off later. The composition is easy to apply, but is toxic and requires compliance with safety measures;

Paint remover in aerosol packaging is very convenient to use

Solvent. Used to degrease surfaces. Personally, I use the P-646 composition; it is inexpensive and well suited for preparing metal for further processing;

Solvent R-646 is used for cleaning and degreasing metal in preparation for insulation

Composition “3 in 1” for metal surfaces . A special composition consisting of paint, primer and anti-corrosion treatment. After application, the surface will be reliably protected from rust for many years. If you have metal without pockets of corrosion, then you can use ordinary primer for metal, its price is much lower;

Special paints with anti-corrosion additives are the best preparation of metal for insulation

Brush or roller . Used for applying paint. For large, flat areas, a roller is more suitable. For designs with many curves and angles, it is better to use a brush.

The brush should have thick bristles to ensure high-quality application of paint or primer to metal

Metal surface preparation:

Illustration	Description of the stage
	A wash is applied to the painted surface . The composition is simply distributed over the metal and left for 15-20 minutes. After this, all old layers of paint can be easily removed with a spatula. If the paint does not come off in certain areas, the treatment is repeated again.
	If there are pockets of rust, the surface is treated with a brush . In our case, we used a grinder with a disk wire cup. With its help you can very quickly remove small layers of paint and rust.
	The surface is painted. Before this, it is simply wiped with a rag soaked in solvent. The paint can be applied with a sprayer if available, but you can also use a brush. If your metal is rust-free and the paint adheres well to it, you can simply degrease it and apply a fresh coat of primer for reliability.

Mounting features

Izolon (penofol) is covered with aluminum foil, which allows for the best possible retention of heat. Its adhesion to the surface of the insulation can be chemical or physical, that is, cross-linked. Izolon may have additional characteristics such as thickness or color. If you are looking for win-win insulation for your home, then this option will be the best choice. It is also perfect for insulating elements of air conditioning systems, pipelines, and production mechanisms. Foamed polyethylene is used for both external and internal work. The material has quite significant advantages.

Among them are:

small thickness;
ease of installation;
environmental cleanliness.

Installation of insulation is possible without the use of special tools. Working with foamed polyethylene does not require additional protection of the respiratory tract and skin. The material is so light that the load-bearing capacity of the glue will not be critical.

How to glue foam to metal

Until relatively recently, foam plastic was mainly used only as a seal for equipment during its transportation. However, it soon began to be used as a finishing material that perfectly insulates heat. You can also often find foam plastic ceiling slabs, stucco moldings and other finishing elements, which significantly facilitate do-it-yourself repair work, reducing the time required for completion and financial costs.

Insulate from the outside or from the inside?

In modern construction, there is a rule: insulate a house from the inside only if it is impossible to do it from the outside. And not by chance. With external insulation, the walls are protected from external influences - atmospheric and temperature, from hypothermia (and freezing), condensation, and extraneous noise. Accordingly, with facade insulation, the building is more durable. This means that in this case the adhesive for insulation should be chosen, intended only for external use.

From all of the above, the logical conclusion follows that the preferred type of home insulation today is facade insulation, using mineral wool insulation. All that remains is to figure out the installation: choose the adhesive for mineral wool and use it correctly.

Attach penofol with the foil side facing the inside of the room. A greater thermal insulation effect is created by an additional air layer 1-2 cm thick (using a backing - sheathing).

By watching the video you will learn more:

Glue of different compositions for polyethylene foam can be ready-made or requires preparation on site. You must carefully read the instructions for the selected mixture:

The glue is applied in an even layer, paying special attention to the edges. Before sticking, you need to wait up to 1 minute so that the composition has time to be slightly absorbed. This ensures better adhesive properties. Attach the treated penofol to the insulated surface. The plates are fastened joint to joint, but not overlapping;
setting time varies depending on the characteristics of the glue (at least 15 seconds);
smooth the surface of the polyethylene foam, removing folds. Tape the seams, you can use foil tape;
glued insulation in residential premises requires additional decorative finishing. The last layer of the structure (plasterboard or lining) is installed on the sheathing.

Nothing brings satisfaction more than a job done correctly and skillfully. If you follow all the recommendations, attaching the insulation will not cause much trouble.