Firstly, a steel door must provide some security features. There are several of these functions: resistance to brute physical force (determined by the strength and reliability of the structure); counteracting “intellectual breaking” (determined by the complexity and “cunning” of locks); counteraction to various kinds of non-standard impacts (there are fire doors, bulletproof doors, vault, panic room doors, doors equipped with access control devices – from simple glass to audio and video systems, etc.)
Secondly, the door must provide initial functionality, protection from the external environment: it must have certain heat and sound insulation properties.
Thirdly, the door should not be nasty in appearance, hearing and smell – that is, it should be somehow decorated, it should not creak and knock, it should be made without the use of toxic materials.
Finally, the fourth group of characteristics relates more to sellers than directly to the product: the door and its parts must be reliable, the seller must give and fulfill guarantees for their products.
Obviously, it is impossible to define an “ideal door”. You must first find out what exactly it is intended for, and then choose a model according to your needs and financial capabilities. Thus, we have formulated the first (and perhaps the main) principle of a “reasonable approach” to choosing a door: first of all, you need to understand what requirements you will impose on products, and, accordingly, which group of characteristics given above will have the main and which one is of secondary importance in further selection.
Door security features
The overall resistance of the door leaf to brute force is an important, but not the only and not always decisive characteristic. Indeed, the door for an ordinary apartment in an apartment building can be relatively weak: if it is broken into with a sledgehammer, grinder or autogen, then the attackers are unlikely to succeed in not attracting attention to themselves.
It is necessary to approach the choice of a door to a country cottage or an unguarded warehouse in a completely different way: in this case, the probability of a “rough break-in” is high, and the design of the door must ensure high mechanical strength of the product.
Unlike brute force, “intellectual breaking” or opening, requires some skill of the cracker and can be carried out almost silently. Accordingly, a burglar has at his disposal an almost unlimited supply of time (practically no lock is able to resist a skilled burglar for more than 20 minutes). This is how a large proportion of apartment doors are opened in big cities. As a rule, the object of “intelligent burglary” is a lock, and, in our opinion, it is the lock that determines (we repeat, in standard urban conditions) the burglary resistance of the door as a whole.
a) you should not save on locks if you want to get a door that is resistant to unauthorized entry;
b) it is better to put two locks, and different systems (cylinder and level) – opening different types of locks requires a specialist with a higher qualification;
c) It is strongly recommended to install special additional protection for locks – armor plates for cylinder locks and armor plates for lever locks;
d) remember: any lock can be opened, so if you think that your apartment can attract the attention of highly qualified specialists, install an alarm. When ordering a door, we advise you to install a mortise reed switch, it will not change the appearance of the door and can later be used to connect an alarm.
We examined the characteristics related to ordinary apartment doors. If for some reason you need a door that has some special properties, then, unfortunately, you will have to sacrifice some indicators: for example, fire doors must be equipped with special locks that can withstand thermal loads, but, as a rule, are less resistant to breaking ; Bulletproof doors are heavier than standard doors, which increases wear on locks and moving parts.
Heat and sound insulation of the door
At the dawn of domestic “door construction”, metal doors had worse heat and sound insulation properties than even the simplest wooden ones.
This is due both to the fact that metal is generally better than wood to conduct heat and transmit sound, and to the fact that wood is a softer and more ductile material, lends itself to a good fit at the installation site (accordingly, in a well-made wooden door there are fewer slots and a canvas the door fits snugly against the frame; it was possible to achieve similar indicators with a metal door, but the cost of this repeatedly increased the cost of the doors of that time).
At that time (until about 2000), the main option was to install two doors: an external steel door, which had a protective function, and an internal wooden one, which took on heat and sound insulation (as well as part of the decorative functions).
Now the situation has changed
An increasing number of companies can offer models of steel doors, which can easily serve as the only door in terms of protective and decorative functions, as well as in terms of excellent heat and sound insulation. Modern doors often even surpass most wooden ones in terms of the latter indicator, and it should be noted that a good wooden door is at least not cheaper than a good steel one.
High heat and sound insulation characteristics of modern steel doors are achieved by the sum of several parameters:
- High-quality seal around the perimeter of the door leaf, preferably in two circuits. To accommodate seals, door frames and leafs are made from special bent door profiles.
- Installation of massive (from 8 mm thick) decorative panels that dampen sound vibrations very effectively.
- The inner space of the door leaf is filled with insulating materials (styrofoam, mineral wool), which prevent the “drum effect”.
- High-quality sealing of gaps between the door frame and the wall, as well as filling the frame itself. The most effective material for this is concrete.
Exterior door trim
A long time ago, there were only two options for finishing entrance doors: painting and covering with various kinds of artificial leather. For reasons of either economy or personal gain, the builders left the front doors bare and painted them with the first paint they came across, and after settling in, the tenants tried to somehow increase the heat and sound insulation and hide the defects of the canvas. “Elite” doors were made with a solid wood panel and varnished (such doors are, for example, in old houses owned by GlavUPDK).
When the first steel doors appeared, their finish did not differ much from the standard one: the metal was painted, covered with artificial leather or upholstered with clapboard. The first two options still exist; lining in Moscow practically died out, but remained in St. Petersburg and provincial cities.
However, in the mid-90s, imported doors appeared on the Russian market, which were finished in a completely different way: Israeli doors (SuperLock, Magen and Mul-t-Lock) were covered with PVC film, and Italian and Spanish doors had decorative overlay panels. Gradually, domestic manufacturers also learned to use foreign experience.
Veneered MDF panels
Judging by our experience, more and more people prefer to install various kinds of panels instead of artificial leather upholstery even on inexpensive domestic doors. Usually thin (up to four millimeters) flat panels are used, as well as thick (from eight to twenty millimeters) three-dimensional panels.
Thin panels can be plastic, or made from MDF. The outer surface of such panels can be covered with plastic film or natural veneer. “Volumetric” panels are made of thick plywood or MDF, or solid wood. In the first case, a milled pattern is applied to a sheet of MDF or plywood, after which the surface is covered with a film or veneer. Solid wood panels are tinted and varnished.
The advantages of paneling are obvious: as a rule, there are much more options for the color and pattern of panels than the colors and embossing of artificial leather; you can choose the color and pattern for the overall design of the apartment; finally, doors with panels just became “fashionable”. Prices for panels depend on the material of the panel itself and the finish. Thin laminated panels cost from 800 rubles; solid wood panels cost at least $500.
To sum up
Both panels and artificial leathers have a common drawback: they are easy to ruin. Therefore, quite often the outer side of the door is painted or coated with a special plastic coating. Unfortunately, both require serious financial investments in equipment from the manufacturer, so quite often the quality of painting leaves much to be desired.
It should also be noted that an ideal vandal-resistant coating does not exist, and replacing a panel is still easier than repainting the canvas (as a rule, you need to take the door away for repainting in the workshop), so STAL recommends installing panels for the outside of the door.