How to Build a Professional Pitchers Mound

Sydney_mound There have been several requests recently about this topic…and for the record….building a mound has several options and this is just one.

First a bit if history:

Rule 1.04 in the MB rule book states, ” The pitchers plate shall be 10 inches above the level of home plate. The degree of slope from a point 6 inches in front of the plate shall be 1 inch to 1 foot and such degree of slope shall be uniform”. The rule book gos on to detail other mound specifics regarding the pitching rubber, the diameter and the size of the level area on top of the mound.

It didn’t used to be this way.  In the late 1800’s approximately 1859,  there was no pitching rubber,  only a  line that was drawn in the dirt about 45 feet from the home plate. A few years later they changed the line to a box so the pitchers could no longer take 2 or 3 steps before throwing the ball from the line. The front line of  the 6-foot square box was still 45 feet from the home plate ….not 60 feet 6 inches like it is today.  Another perspective is that the distance between home plate and the pitchers mounds initially was measured from the front foot of the pitcher during the early days of the game not as it is today where the distance is measured from the back foot.

In those days the batters were actually allowed to tell the pitcher where he wanted the ball thrown. In about 1882 they decided to move the “pitchers box back to 50 feet because it was beginning to be to tough on the hitter.  A few years later they changed the rules again to make the pitching box a little smaller and the batter lost the control of telling the pitcher where to throw the balls.

During or around 1893, a pitcher’s plate made from wood not rubber was used.  This pitching plate was installed about five feet behind the back edge of the pitchers box which gave us the 60 feet distance.  The difference in the measurement of 60′ 6 inches  and what was measured in that era was “supposedly” blamed on the groundscrew for not measuring the distance correctly. They probably had to blame it on someone and the groundskeeper was as good as any!

One must remember the pitchers mound was still flat during those years until they set a height of 15 inches in 1903.  There is really no written notation of the word “mound” until the 1903 rules were formed.

The mound has remained the same distance from home plate for over 100 years. The next big change took place in the mid 1960’s when during that era, pitchers were dominating the game.  Low ERA’s and both leagues naming pitchers MVP’S caused ownership to make another change around 1967. Following a season where Bob Gibson had a 1.12 ERA and Carl Yaztremski won the batting title with a 301 average, the mound was lowered to 10 inches in 1968.  And if that wasn’t enough to change the game and make it more offensive,  along came the DH a couple years later in 1973. Dscn0418With that change we saw an adjustment in the pitchers mechanics from the “stand tall and fall”  windup to the “drop and drive”.

Today it appears things are swinging back the other way and they may need to make a change to the mound again (or get rid of the DH.)  Only time will tell.


Tools and materials:

Plate compactor, hand tamp, landscape rake, transit, garden rake, an assortment of shovels, (round point and flat) string,  24 inch spikes, 6 foot level, plywood planks,  hammer, water and water hose, two kinds of clay. Hard and regular infield mix.  Hard as in 50% clay 10% silt and 40 sand. These can fluctuate a bit but you should have the material tested to be sure it meets a a very high clay content. You are going to need abut 6 to 10 tons of hard clays and infield clay type material, a cart or loader to move the clay in…some people use the baseball team w/wheelbarrels.  Dscn0420 Hard clay comes in bags and bricks.  Either work fine but for maintenance I prefer the bags.

1.  Set the distance ,height and exact location you are needing to establish  your mound using a transit or laser leveling tool.  A professional mound’s pitching rubber is set 10 inches above the home plate.  Check it by running a string through the center of homeplate to pitchers mound the second base.  Keep this string handy as it will be a guide to making sure the plateau is centered.

2. After setting your distance to the pitching rubber..Lets say it is regulation at 60’6″ then measure 18 inches  in front of your 60’6″ mark to find the circumference of the mound.

3. The circumference is the width of the mound… which is 18 feet.  It is now important to remove 4 inches of material from the circle. Put some plywood around the edge of the mound so you trash dont your turf while you are building the mound. Using strings and the 24 inch spikes can help keep you stay on track after setting the mound height. I have seen where guys will take a string across the mound 1st to third and place the pins right at the base of the mound…if you don’t have a transit some folks will use a “line level”  These instruments are not a 100% but will get you close. Use this cross line to check height as needed.

4.  Use the plate compacter to harden the area. Bring in the softer clay 60/30/10 to build the base.  The base is the area directly under the plateau of the mound. The plateau is 5 feet wide and 36 inches deep.  Raise this area in 1 inch lifts.  Water then plate tamp after each lift until you get to about 4 inches from your finish height of the mound

5.  Now place your pitching rubber in the desired location. Make sure a string is ran from the plate to second base to establish the center of the mound and the center of the rubber. It helps to take a pen and draw a line through the center of the rubber as you are setting it in place

6. Check your level and height using a transit.

7. Begin to add the “hard clay around the pitching rubber to set it in place.  Use the hand tamp during this period. Also use a small hand level to make sure the rubber is level.

8.  Continue to build the plateau in lifts of 1 inch then tamp then water. then add… then tamp… then water…. etc,Dscn0481

9. Once you have the plateau built you will need to start the slope. Remember the fall is 1 inch per foot towards home plate.

10. Take a board about 10 feet long, (the straightest one you can find) and mark it at every foot starting first foot 6 inches from the rubber. Block up the board so it is level. Some people build a big “T” at the end of the board so it can stand without some one holding it.  You can purchase a pitching slope frame from Beacon Ball fields or beam Clay. These are metal poles that are designed to check your slope daily.

Mound_diagram 11.  The entire landing area is made from the hard clay. It is about 7 feet wide and 8 feet long. The sides and back of the mound can be made from infield clay… using the same 1 inch per lift…plate tamp, water, then 1 more inch…plate, then water,…etc until you have the slopes completed always checking your plateaus

12. Maintaining moisture is the key to the mound…don’t let it dry out and crack. The idea is to keep it moist so it is pliable and gives the players Superior footing.  Get a tarp and spike it down and always keep it covered when not being used.

We can talk about maintenance of the mound later on..that’s another blog in itself.

Hope this gets you guys/gals started on the right foot. I have seen several methods and this is just one approach. Some people actually build the entire mound out of infield mix first and then take out the landing area and soft clay around the mound and then replace it…sort of like a cookie cutter method.


I never knew there was so much history change to the pitcher’s mound… I take care of a high scool field in VA and this is the best information i have seen on mound building!


Coach B

I would appreciate it if anyone seeing this is aware of a convenient way to build backyard mound. I’ve found one method a few weeks ago and now I can’t access the site. Thanks.

Does anyone know how to build a portable pitching mound or know where I can get instructions on how to build a portable pitching mound?

Where can you buy the clay for building up the mound

Found some suppliers local in Wisconsin
Waupaca Sand Solutions& FLEX-A-CLAY in Iowa. Menards carry garden line and that can be used with some sucess but you need clay.

“You are going to need abut 6 to 10 tons of hard clays and infield clay type material, ”

Is that right – 6 to 10 TONS of material? Can anyone estimate the cost for building one? Suppliers? Time frame? Difficulty? I would really like to help upgrade the local diamond, which serves as home field for youth baseball, junior high, high school, and town team games.

Hi Murray

I run a ball club down here in Australia, and I am finding it quite hard to find the right materials. I have been looking around various brickworks for unfired clay bricks, possibly similar to the bricks in the pictures on this blog post. Are the bricks you supply already air-dried, and then once wet become more malleable?

I have spoken to a major brick works in Melbourne and they are asking whether I want “green” (ie just pressed and still wet) or air-dried bricks.

Any help would be greatly appreciated,

Mr G Powell
Monash University Baseball Club, Melbourne Australia

We recently rebuilt out mound using gray clay bricks. All seemed to go well with the job but we are having problems with the repairs after use. They will not set up and harden. They want to remain soft enough to push your finger into the clay. I have followed the Turface instructions but they leave some to the imagination. Our mound surface material is a bit on the sandy side so would the Turface infield material make a difference on top? Could you please give my the idiots guide to repairing the hole in front and at the landing area. Thanks for any help you can be.

John –

Couple of questions. The Gray clay bricks…. are they moist? By moist you should be able to push your finer nail into the brick. If you cant then they are to hard an will not bind with the new moist material . Also in order to repair the areas properly you need to remove all of the old soil and contaminated clay from the hole. I mean ALL. Any where you have some infield conditioners or infield clay on the clay bricks…it must be removed entirely or it will not bind.
Also check to make sure the bricks are not covered to much. Only should be about 1/8th inch of other material on top ….. and makes it easier to repair.

I can’t even get the clay repair to skim over hard. The problem so far is not that it does not bind, it won’t harden up at all. I have tried both covering it as recommended and leaving it open to dry. Both with no success. Is there anything I can add to the clay to get it to harden. I played the game professionally for 15 years and have been on about every type mound, from rock hard where you have a hard time even scratching out a hole, to clay that you can put a cleat into but stays firm. I can’t figure this out. It wants to stay the consistency of modeling clay. Thanks again for any help you can be.

John – A couple other suggestions. Obviously you need the sun , wind and some warm weather to dry out the clay in order for it to harden up. even modling clays will turn to brick once they dry out. If your ballpark is up north you are not alone with the problem. Another option is to put a vibratory plate tamp on the mound and really let the machine smooth and tamp the areas. This will help firm the clays more. If you are still having no luck I would have to say you should consider a replacing your mound clay. It sounds like it is not the typical mound product we use if your still have trouble getting it to firm up. Murray

Beauty is indeed a good gift of God; but that the good may not think it a great good, God dispenses it even to the wicked. Do you think so?

How soon after you build a pitchers mound can you start to use it? Our existing pitchers mound is in desperate need of repair, but our season is about to start. Thank you, SS

you can use it the next day if the clay is handled right the key is managing the moisture. not to much not to little.

Hey There. I found your blog using msn. This is a really well written article. I will make sure to bookmark it and come back to read more of your useful info. Thanks for the post. I’ll certainly return.

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