What type of door would be hardest to break down? Are there windows within or alongside the door that could easily be broken, allowing a burglar to reach in and access the lock? Are the locks built with high grade steel or something cheaper?

Let’s take a look at what you should look for in a door to ensure it won’t be easy for a thief to bypass.

Door Material

It’s a common assumption that steel or fiberglass doors are more secure (harder to break down) than a wood door, but this isn’t actually what we need to worry about. It’s not the door but the latch-side jamb that is the weak link in any exterior door. A forceful kick can split the jamb without actually damaging the door itself.

To prevent someone from damaging the jamb, install an extra-long security strike plate. Sink three inch screws into the neighboring stud.

Door Thickness

While the jamb may be the weakest link, that doesn’t mean the door itself shouldn’t be stout. Choose a beefy 1 3/4th inch thick door over the standard 1 3/8th inch models. These thicker doors still accept standard locksets (if you go thicker, you’ll need a special lock and bigger hinges).

Glass

Many homeowners find a glass window in or beside a door attractive and also appreciate the natural light it allows in. Choosing a door with regular window glass or even tempered glass makes a tempting target for burglars though, since these types of windows can be broken, allowing access to the lock.

Instead choose a hurricane-rated glass. These types of windows feature an unbreakable inner plastic layer.

Hinges

To ensure the hinges are securely anchored to the stud, choose three inch long screws.

Locks

Mortise locks are usually constructed with higher grade steel than average bored locksets you’ll pick up at the home improvement shop. Spend a little bit more for the added durability and security.

Source: March 2009 issue of This Old House

There are quite a few extra security devices you can get for your doors that add even more protection. Today we’ll take a look at hinge bolts, rack bolts, self-locking bolts, door chains, and door limiters.  Any of these types of door hardware can improve your home’s security, and they are relatively inexpensive to install.

Hinge Bolts

Hinges bolts are a good idea for doors where the hinges are on the outside (if a burglar can access the hinges, he can jemmy them and gain access without messing with the locks at all).

To add security to your hinges, install hinge bolts about 75 mm away from the hinges. You need two per door.

Rack Bolts

A rack bolt is a bit like a deadbolt except that the bolt is secured with a fluted key instead of a thumb tab. This makes it very hard for a burglar to get the right angle for unlocking the bolt if he breaks a side window and is trying to reach around from outside.

As for installation, rack bolts are mortised into the opening edge of the door. For extra security you can fit two to each door, one up top and one down below.

Self-locking Bolts

If a door is too thin for a rack bolt, consider a self-locking bolt. These bolts are surface mounted, meaning they are installed on the interior side of the door instead of within the jamb.

With a self-locking bolt, you simply push the bolt end to slide it into the locked position. These are very simple to install.

Door Chains

Just about everybody is familiar with door chains. They are helpful in case an intruder poses as someone you’d open the door for and then tries to force his way inside once you crack the door. A door chain prevents the door from opening more than a few inches. (Note: a peep hole is always a good idea so you can see who is out there before opening up!)

The strength of a door chain depends on how well it is anchored to the door and the frame, so it pays to use the longest and heaviest-gauge screws that will fit.

There are numerous door chain patterns available. Examples include a simple chain, a chain combined with a sliding bolt, a chain that can be unlocked from the outside with a key, and even a chain with a built in alarm that is triggered when someone tries to force his way inside.

Door Limiters

The last type of door security hardware we’ll look at is the door limiter. This is basically a more substantial version of a door chain. It has a sliding bar that replaces the chain.

When it’s in place, the bar engages with the retaining part of the unit to restrict the opening of the door. The door must be fully closed and the bar swung away before entry can be gained.

There go you: some extra security options for your doors.  All of these pieces of hardware are quite affordable, so consider taking this simple step to beef up your home’s security!