How do you tell if there is concrete behind drywall?

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If there's no drywall, just knock on the wall. If the wall feels as hard as concrete, it probably is. If there is drywall, take a drill and a very small bit and drill a hole somewhere inconspicuous. If the bit stops going after an inch or two the wall is concrete.



Then, how do you know if wood is behind walls?

A good starting place is 16 inches from a corner. For better precision, use a tape measure and mark 12 inches, 16 inches, and 24 inches from the corner. Tap the wall at each distance. You'll hear a solid sound when you tap the part of the wall that is supported by a stud.

One may also ask, how do you tell if you have plaster walls or drywall? Push a thumbtack or pin into the wall in an inconspicuous spot to test its hardness. Drywall is softer and won't crack. Plaster is much harder. A plaster wall won't want to take the pin and will probably splinter.

In this way, what is behind a drywall?

Drywall is the rigid gypsum-based board that forms most walls in homes. Often called wallboard, drywall is usually 1/2-inch thick. It is either screwed or nailed directly to the wall studs.

Can you hang a TV on drywall?

Use a toggle: If there simply aren't any studs where you want to mount the TV, then you need to use some sort of hollow wall anchor. Mounting a TV on drywall or plaster without attaching to a stud can be a very safe and reliable solution IF you know the limits of the wall and the toggles.

39 Related Question Answers Found

What is Blueboard?

Blue board drywall is also known as plaster baseboard. Blue board is used for veneer plastering, and the surface paper has special absorption qualities. It has a high water and mold resistance and there are fewer steps involved in veneer plastering. Blue board drywall is not made for mud, tape, or paint.

Is sheetrock the same as drywall?

Drywall is a panel made of gypsum plaster pressed between two thick sheets of paper. It is used to make interior walls and ceilings. Drywall construction became prevalent as a speedier alternative to traditional lath and plaster. Sheetrock is a trademark for drywall made by the US Gypsum company.

Do it yourself repair drywall?

drywall panels
  1. Step 1: Outline the Damaged Area with a Carpenter's Square.
  2. Step 2: Cut the Sides with a Keyhole Saw or Utility Knife.
  3. Step 3: Cut the Support and Install in the Wall.
  4. Step 4: Cut the Drywall Patch to Size.
  5. Step 5: Install the Drywall Patch with Drywall Screws.
  6. Step 6: Complete the Drywall Patch.

When did drywall start being used?

Drywall was invented in 1916. The United States Gypsum Corporation, a company that vertically integrated 30 different gypsum and plaster manufacturing companies 14 years prior, created it to protect homes from urban fires, and marketed it as the poor man's answer to plaster walls.

What was used before drywall?


Before drywall became widely used, building interiors were made of plaster. It has been around for millenniums. Their first use of gypsum in construction appears to have happened in 3,700 B.C. when the Egyptians used plaster and gypsum blocks over woven straw lath in building the pyramid of Cheops.

How do I know where the studs are in my wall?

You can find studs with an electronic stud finder or you can try to find them manually. If you have drywall walls, a stud finder locates studs quickly and accurately. It's less effective on lath / plaster walls, but some have a metal-scanning feature that may locate the nails securing the lath to the studs.

Is there a stud finder app?

Stud Detector is one of the best stud finder app for android users which allows you to easily ind metal framing studs. It is simple, easy to use and free android app which works on basis of magnetic field and compass apps. You can also use it as to know magnetic field from your android smartphone.

How do you tell if you're drilling into a stud?

Make a fist and knock on the wall with your knuckles. In some places, you'll hear a hollow sound. Other areas will sound more “solid.” The “solid” sound indicates you have knocked on a stud. Measure 16 to 25 inches away from either side the first stud and rap on the wall again to hear if you've hit another one.

Can you drill into a stud?

Once you find the stud, get out your power drill. A large bit shouldn't be used when drilling into a stud since the stud is strong enough to support the weight of your hanging items without special hardware. Insert the drill and pull it out slowly once you've made your hole into the stud.

How do I find a stud with a magnet?


Use magnets to help locate the screws in the studs, but also try to imagine the hidden structure underneath. While magnets are usually helpful, the process is easier if you look for some underlying clues. Many studs are spaced about 16 inches apart. Start your search from one edge of the wall, and work 16” from there.

How much weight can drywall hold?

How much weight can drywall hold without anchors? This can be 5 to 10 pounds, but keep in mind that the drywall is an extremely brittle material and, it is not strong enough to hold the weight for a longer period of time.

How much is a stud finder?

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What is a good stud finder?

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  • Best Overall Stud Finder: ProSensor 710 Franklin Sensors at Amazon.
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  • Best Magnetic Stud Finder: CH Hanson 03040 at Amazon.
  • Best Stud Finder for Plastics: DeWalt Wall Scanner at Lowe's.
  • Best Stud Finder for Metals: Zircon MetalliScanner M40 at Amazon.

Can you put plywood behind drywall?

Yes, plywood can be used behind sheetrock. I just finished a bathroom, a small bathroom where every inch counted so I infilled between the studs. Yes, it was a bit labor intensive but now a grab bar or towel bar can be added anywhere without the worry of it being pulled out of the sheetrock.

How deep are studs behind drywall?


When a home is framed, the wall studs are usually spaced 16 or 24 inches apart. If you start in a corner and measure out 16 inches and you don't find a stud, you should find one at 24 inches.

How thick is a lath and plaster wall?

A traditional 3-coat plaster is typically 7/8″ thick and when you add in the 1/4″ wood lath that supports the plaster wall, you have a wall that is more than 1″ thick! Compared to today's most common drywall thickness of only 1/2″, that is a difference worth noting.

Why is my wall squishy?

There are two different causes for soft drywall: moisture and wetness. They may sound like the same thing, but there are subtle and important differences. The biggest difference is that a moisture problem doesn't always mean a leak, often moisture build-up is caused by improper venting.