Made-to-measure security doors, in the right class

For the standard, none: the scale of burglar resistance classes is the same. The difference is in the use. A security door is the one to a flat, opening onto a landing, that is, onto an internal, dry space. A security front door is the one opening directly to the outside, the entrance of a detached or independent house.

What changes is what it has to be able to do. An external front door takes sun, rain and wind, so it needs weather gaskets, a thermal break on the frame, panels made to live outdoors and a threshold that does not let water through. A flat door can do without all that and concentrate on security and sound insulation.

The test tools and the minutes change. In class 3 the attack uses a second screwdriver and a crowbar, that is, a real lever, and the door has to hold for five minutes. In class 4 impact and cutting tools come in, hammer, chisel, axe, saw and cordless drill, and the time goes up to ten minutes.

In practice class 3 covers a ground-floor entrance, a detached house, a door facing the street or a garden well. Class 4 makes sense when the house is isolated, is left empty for long periods or has no neighbours who might hear. Above 4 you leave the home and enter the world of businesses and warehouses.

None, if you look at the standard. EN 1627 knows only the six burglar resistance classes, from 1 to 6. 'Armoured' is a commercial name, not a certified level: it usually indicates a heavier structure, with thicker sheet or extra reinforcement, but there is no test that defines it.

When you compare two offers, forget the adjectives and look at the declared class and the document that certifies it. Check as well that it refers to the complete door with its frame and not to a single component.

Yes, and the class is not lost if the glass is the prescribed one. On security elements you use burglar resistant glass certified to EN 356, laminated with several sheets and films: for a class 3 door, for instance, the standard asks for P5A glass. The glazed part has to be tested together with the door, otherwise the class written on the certificate no longer applies.

Glass is at its best in front doors with a transom and side lights, which on independent houses are the most common choice: the entrance stays bright and with satin glass you cannot see in from outside. It costs more than a solid panel and is one of the items that shift the quote most.

There is no single price, and anyone who gives you one over the phone without having seen the opening is giving you a bait number. Five items shift the total: the burglar resistance class, the size and shape of the opening, because double leaf, transom and side lights are extra elements to build, the panels inside and out, the glass if there is any, and the lock with its cylinder.

Then the fitting weighs in, very differently depending on whether the old subframe is reused or has to be demolished and made good. When you compare two quotes, check the same things are inside them: certified class, frame, panels, removal of the old door and disposal. With us the site visit is free and the number that comes out of it is the final one.

The most common sizes are 80 and 90 centimetres wide by 210 high, referring to the clear passage, that is, the void left when the door is open. The hole in the wall needs to be a few centimetres bigger, because it has to take the subframe and the frame.

On the entrances of independent houses the standard barely exists: there are wide openings, transoms above the door, glazed side lights and stone thresholds already laid. There you work to measure, and we take the measurement at the site visit: an error of a centimetre on a security door cannot be recovered by widening the architraves.

First goes the subframe, the rough frame that stays in the wall: it is fixed to the masonry with straps or anchors, in the number and at the points indicated by the manufacturer, and it has to be level and square. Then the finished frame is hooked on, the leaf, which is heavy, is hung, and finally hinges, deadbolts and stop are adjusted.

The part almost nobody talks about is that the burglar resistance class only holds if the fixing follows the test instructions. A certified door anchored with four plugs into hollow bricks, or held up by polyurethane foam, in practice goes back to being an ordinary door. That is why at the site visit we look at the wall too, not only at the opening.

Almost always it is the hinges, which on security doors adjust on three axes: in height to lift a leaf that has dropped, sideways to recover the gap, and in depth so it beds down better on the gasket. You work with an Allen key, one screw at a time and half a turn at a time, trying the closing after each turn.

If instead the leaf is level but the key turns stiffly, it is usually the latch and deadbolts no longer finding their housings on the frame: there you adjust the striking plates. A practical tip: never force the key to get the bolts in, because it ruins the lock, and a lock costs far more than an adjustment. On doors we fit, we come and do the adjustment ourselves.

In most cases you do not replace the lock, only the cylinder. On euro-cylinder locks you take out one screw on the edge of the leaf, slide the old cylinder out and put in a new one of the same length: it is a ten-minute job, and it is what you do when keys are lost or you buy a house from someone else.

It is worth taking the chance to move up a level: there are cylinders with protection against drilling, bumping and pulling, and the defender, the plate that protects the cylinder from outside, counts as much as the cylinder. On old double-bit locks there is no cylinder: there you change the whole unit, and it is often the moment to move to a euro-cylinder lock.

On the panel a soft cloth with warm water and mild soap is enough. Avoid solvents, alcohol, acetone and abrasive pads, which dull the finish. On a real wood outer panel you need products made for outdoor use, and it has to be gone over now and then, because sun and rain work all year round.

The maintenance that really counts, though, is another: once a year lubricate the hardware and the cylinder. On hinges, bolts and latch a silicone or PTFE spray is fine. Inside the cylinder never oil, which cakes the dust: use powdered graphite or a spray made for locks.