We should start with two short statements:

Rules of thumb:
First: There is no fully burglar-​proof hard­ware!
Sec­ond: There are no fully burglar-​proof win­dows either!

There is sim­ply no way for the join­ery indus­try to man­u­fac­ture win­dows that would guar­an­tee com­plete secu­rity against bur­glary. We can only dis­cuss win­dows and hard­ware that is more or less resis­tant to intrusion.

So far the fun­da­men­tal doc­u­ment relat­ing to the issue of hard­ware bur­glary resis­tance is the stan­dard ENV 1627:2006 which estab­lishes 6 win­dow secu­rity classes. From the Ger­man word “Wieder­stand­sklasse” (resis­tance class) it has also become nor­mal to talk in Poland of so-​called “WK” classes, for exam­ple, WK 1, WK 2. Class 1 is the low­est level of secu­rity, class 6 is the high­est level of security.

Resis­tance classes

Bur­glary resis­tance class answers the ques­tion of how long a win­dow will with­stand unau­tho­rised attempts to open it from the out­side by using dif­fer­ent sets of tools and var­i­ous forces.

Resis­tance to bur­glary is a char­ac­ter­is­tic result­ing from the con­struc­tion of the win­dows, as well as with the selec­tion of appro­pri­ate mate­ri­als for a design. Buy­ers, as well as sell­ers com­monly use the term “burglar-​proof”. This is in fact an incor­rect and mis­lead­ing term, because win­dows that would be 100% burglar-​proof do not exist.

Depend­ing on the selec­tion and arrange­ment of hard­ware they can belong to dif­fer­ent bur­glary resis­tance classes. The WK index deter­mines the time needed to force entry through the struc­ture of the win­dow. Three classes of solu­tions are most preva­lent on the market:

  • WK1 – a win­dow that can­not be forced using only brute force (with­out tools);
  • WK2 – a win­dow that can­not be forced for 3 min­utes using sim­ple tools (screw­driver, pli­ers, tongs, etc.);
  • WK3 – a win­dow that with­stands even a steel crow­bar for at least 5 minutes.

When choos­ing one of the types of bur­glary pro­tec­tion, it is nec­es­sary to remem­ber that the hard­ware itself is not enough. An impor­tant ele­ment of the whole set of anti-​burglary ele­ments is the anti-​burglary glass and door han­dle with a key or button.

If win­dows with ele­ments inhibit­ing bur­glary are cho­sen, one should also con­sider equip­ping the win­dows with con­tact sen­sors. Con­tact sen­sors are a sim­ple and effec­tive sen­sor of open win­dows and doors that forms part of a secu­rity sys­tem or access con­trol sys­tem. It is impor­tant that for a con­tact sen­sor to be installed in all win­dows and doors it pro­tects the build­ing against intru­sion attempts at the stage of the attempt, as opposed to motion detec­tors located inside a build­ing. A con­tact sen­sor works on the basis of a mag­net and a tube with embed­ded circuits.


Fot. Kon­tak­tron

Open­ing the win­dow breaks the elec­tro­mag­netic cir­cuit. Each sen­sor is con­nected to an alarm con­trol panel. When leav­ing the house, it is not pos­si­ble to arm the alarm when any win­dow is not closed. Con­tact sen­sors are installed at the man­u­fac­tur­ing stage of windows.

A sim­i­lar but much more expen­sive solu­tion is a con­tact sen­sor inte­grated with cir­cum­fer­en­tial hard­ware. This also works on the basis of an elec­tric cir­cuit, but with the dif­fer­ence that just a slight manip­u­la­tion of the hard­ware or han­dle is enough to set off the alarm. This sys­tem also requires all win­dows to be closed prior to the alarm being armed.