The buyer, as a rule, listens to what the seller tells him, not really understanding the intricacies and quality criteria of steel doors. But a decent appearance and an acceptable price are not the main things to look for when choosing a door.
Find out which filler is used. Manufacturers install a filler between the steel sheets of the door to improve the heat and sound insulation properties. It can be polystyrene, pine or special “backfill”. The best and most advanced filling material is mineral wool. It does not support combustion, is environmentally friendly, and provides high heat and sound insulation. But, with unqualified execution, problems with the lock may arise.
Polyfoam over time begins to release toxic chemical compounds, so it is better to choose a wooden bar. The filling of Italian or French doors is high density polyurethane. They fill the inter-sheet space of the door under pressure under factory conditions, providing the highest thermal insulation.
Attention to the castle. First of all, he must attract us with his reliability. No-no … no one but me. And it is better that the door is equipped from the inside with an additional bolt. Some companies install a door opening limiter – an improved version of the door chain. Thanks to him, the door, without your permission, cannot be opened more than 5 degrees.
Next: remember – nothing is eternal. Even the most reliable and most western-branded lock is not immune to breakage. Therefore, we find out from the seller whether it is possible to replace the lock (there are cases when it is tightly welded and the replacement can be done only by changing the door). A good option would be a lock with a replaceable core, which can be easily replaced on your own..
And finally, clarify how the issue of opening the door in case you lose your keys is resolved. “Fireproof” qualities of the door. Find out how the door will behave in the event of a fire. What quality guarantees does the manufacturer provide in this case? Many doors jam from high temperatures. Therefore, it is better to choose a steel door more expensive, but with fire-resistant properties..