For bulletproofing housewalls, which would be better to put inside the thick walls? Ceramic or metal plates?

The best bulletproofing is shooting back and neutralizing the initial shooter! Bang, Bang!! That ought to take care of the problem quite nicely.

Ceramic plates are way to expensive..... metal plates arent that great but are cheap and if used properly can stop a variety of bullets.... Funny you should ask this today.... I took 3/16ths inch metal plates to the gun range today and 7.62x39MM, 30/06 and .223 rifle cartridge bullets cut thru it like hot butter at 100 yards... On the other hand .45 and 9MM pistol rounds were not able to go thru the metal at 50 yards.... I wouldnt get to hung up on the grade of metal.... What seems to work for me is layers of metal... A couple of 1/4 inch steel plates will stop most rifle bullets..... In one part of a house in a crappy neighborhood the owner had me put 1/4 inch metal plates and filled the rest of the interior wall area up with layers of drywall 5 1/2 inch thick..... You could also use metal plates in the wall framing and fill in between with sand.... be sure the houses structure can take the weight..... I worked with this one guy that lived in a crappy neighborhood with low life gang types shooting up the place.... He put a 1/2 inch thick metal plate behind the couch where he sat and watched TV.... It was in the front of the house and also was the safest place to sit.... Bulletproofing a house can be real expensive - more like cost a fortune... Have the fascade of the house covered in brick... Or just bullet proof only the areas where you sleep or watch TV or any other area you spend some time it...

It is not a matter of the type of material, but the thickness of that material. A very thin sheet of one won't be as effective as a 2 inch sheet of the other. In general, inch for inch, ceramic is stronger and lighter, but more expensive. Also note, not all steel is equal, you will need special hardened steel.

Finally, the most effective and economic bullet stopper is sand/dirt. If I had to make something bulletproof, I'd make two walls about 2-3 feet apart, and fill the internal space with sand or dirt

Jsied, is the stuff you are talking about the same as this stuff here? http://www.theboxotruth.com/docs/bot34_3.htm

If I were to bulletproof a place, I wouldn't worry about stopping a 44 mag, I'd worry about the guys with rifles!

You can bullet proof any construction with laminated fiberglass ballistic protection in readily available panels.

These panels get thicker & heavier as more protection is required. A 1/2" thick, level III panel will stop a .44 magnum. thicker- higer rated - material can stop various rifled slugs & bullets

see the link below - looks like the same stuff used in the pictures linked by akluis. That link does not tell us the thickness or classification of the material. The fact that most bullets went thru does not mean the material failed, just that the wrong material was used.

There are a lot of ways to bulletproof a building, Thinner layers of absorbing materials (see links) can easily be added to existing house construction without extreme modifications.

For the longevity, I would prefer the metal plate.

not sure hte purpose... but if trying to create a "safe room" that can take a few shots

The Ceramic, once struck (depending on the make ,etc) can loose it's effectiveness.

for my $$... Steel plate.

I would also completely coat the walls in a "rhino lining" type of material used for linting truck beds. This will help the wall maintain some integrity if multiple shots are made and penetrate the block wall.

Our shooting range starts with a total of 24" of cement lined every 6 inches with steel sheeting and sealed with a ceramic compound purchased from a former military vendor. We chose this because there is a neighborhood in the area and got a break for the supplies by buying bulk. That is the back wall. The interior side walls are composed of two rows of cement filled and steel reinforced cinder blocks. I'm not sure what you want it for, but we built this based on a design obtained from a U.S. Marshals' indoor range in Virginia.

I have a Gold plated curling Iron and a Ceramic flat iron..for straightening hair, use the Ceramic Iiron...It is about how the hair slips thourgh the tongs of the tool

This is a very specialized question which it would need a true expert to answer but I do remember visiting the presidential palace of the country that I lived in many years ago after the military had attacked with small arms. There must have been thousands of pock marks and not one bullet had gone through the walls which were very thick and made of adobe.

In addition to the other excellent answers, I wish to suggest you do a Browser search on the Dicker Stack-sack Home construction method. He uses burlap sacks filled with concrete mix, dipped in water, and laid like bricks, with pointed steel rebar spikes driven down into them as you advance in the construction while still wet. The walls are as thick as the bags are wide, plus sprayed concrete troweled out smooth. Commercial-style plumbing and wiring in visible conduit and pipes, cover all code needs. Plus, it is "resistant" to gunfire. Regards, Larry.

Just build a monolithic dome house...... In addition to bulletproof, they are tornado proof , wildfire proof, earthquake proof, lightning proof and a whole hols of other proofs.

And for not much more cost then building a stick house.