Security Classes RC1-RC6 Explained for Prague Renters

Apartment listings and door hardware in the Czech Republic sometimes carry an "RC" rating - RC2, RC3, and so on. If you've moved to Prague and seen this on a lease, a door, or a cylinder box and had no idea what it meant, you're not alone. It's a resistance classification, and understanding it takes about five minutes.

The classification comes from ČSN EN 1627, the Czech-adopted version of the European standard for burglary-resistant building products. It rates how well a door, window, or lock system resists a forced entry attempt - and it's the only standard worth citing here, since it's the one actually printed on certified hardware and used by locksmiths, manufacturers, and insurers in the Czech Republic.

What RC1 to RC6 actually mean

The scale runs from RC1 to RC6. The higher the number, the more time, tools, and effort it takes to force entry - and the longer an intruder is exposed to being seen or heard before getting through.

What class does a Prague apartment actually need

For a flat inside a secured apartment building - one with a locked street entrance and, ideally, an intercom - RC2 is usually adequate. If you're on the ground floor, in a standalone house, or in an area where break-ins are more common, RC3 is a reasonable step up. Offices, storage spaces, and anywhere with valuable equipment on-site should look at RC4 or higher.

If you're not sure what class your current door or cylinder already has, check the box or certificate it came with - certified hardware is required to state its class somewhere in the documentation. If you don't have that paperwork, a locksmith can usually tell from the door, fitting, and cylinder type on site or over the phone.

Renting long-term? What expats should know about cylinder upgrades

Most expats renting in Prague aren't in a position to replace an entire door - that's the landlord's call, and their expense. What you usually can do, with permission, is upgrade the cylinder. It's a fast, relatively inexpensive change that noticeably improves resistance to picking, drilling, and bumping without touching the door itself.

A few practical points if you're considering it:

• Ask your landlord first. Most landlords in Prague are fine with a cylinder swap, especially since it's a low-cost security improvement to their property - but it's still their door, and it's worth getting a quick yes in writing (a text message is fine) before booking anyone.
• Keep the original cylinder. Put it somewhere safe so it can be reinstalled when you move out, or hand it over to the landlord along with the new one - this avoids any dispute about what happened to the original hardware.
• Get a receipt. Useful for your own records and occasionally relevant to a security deposit conversation at the end of the lease.
• Check key-copy rules on higher security cylinders. Some high-security systems (like EVVA MCS or AirKey) restrict who can order spare keys and require a security card - worth knowing before you need a copy made for a visitor.

A cylinder upgrade won't change your official RC rating on its own - that applies to the certified door system as a whole - but it closes the most common point of attack and is one of the few security improvements a tenant can usually make without a major conversation with the landlord.

If you're dealing with a lockout rather than a security upgrade, see Locked Out in Prague? Here's Exactly What to Do. And if you want to know what a cylinder swap or a callout actually costs, check Emergency Locksmith Prague: What It Really Costs.

Read next: Locked Out in Prague? Here's Exactly What to Do →