Building A Block Pit

Below are the plans for building your own no-frills pit suitable for a butterflied 75 to 100 pound hog, enough to feed about 35 people. It is designed so it can be a temporary structure or you can add some mortar and make it permanent. If you cut the head and remove the feet at the knees and elbows, you can fit a 100 pounder or more on this rig. But don't throw away the head and feet. Just place them on the stretcher next to the torso or boil the head and make souse meat. The feet can be pickled in vinegar, beet juice and some spices for a great classic southern snack.
This size pit can usually be built for $200.00 or less. If you plan on cooking larger hogs, you can scale this plan up.
Originally this type of pit was used with direct heat (The fire directly below the meat). People would just scatter a few coals directly under the hog. More coals in areas under the hog where they wanted more heat (shoulders and hams) and less in areas they wanted a lower heat such as the loins. This method can reduce your cook time a little bit, but unless you are very proficient at managing a fire, I strongly suggest you incorporate the the "heat shield" listed below so you will be cooking with indirect heat.
There are many more designs on the internet as well as many YouTube videos showing step by step construction. This is just one of the simplest.

Detailed Instructions At The Bottom Of The Page.

This shows the basic size and layout of the pit. Notice rebar in the upper and lower left photo as well as the openings at the bottom in the 2 lower photos to add and move coals.

This depicts the pit in use. The tin top is in place and the end holes have been blocked with a piece of metal and a log when not being used to add coals. Notice the blocks turned sideways on each side of the pit wall to provide ventilation.

An overhead view. Notice the hog is offset a bit to one end and the burning coals are at the other end rather than directly under the hog when not using a heat shield.

Shows one of the holes on either end uncovered. This is where you will add additional coals or use your hoe or rake to move the coals around during cooking.

The most important feature of your pit. A good oven thermometer to monitor the inside temperature of the pit without opening it. An even better idea is to insert the probe from your digital thermometer into the opening between the blocks. With a digital you will get a much more accurate reading, and, if you have a wireless digital, you can even monitor your pit from a distance.

Materials Needed

SIDES:
54 concrete blocks 16"x 8"x 8". This will get your hog 32" above the embers, plus a course to hold the lid. Cost about $54.00.

LID:
1) 4' x 8' sheet of 1/4" plywood, cut down to about 44" x 60" for the lid. Cost about $10.00. Usually the lid will not be a tight fit. If it is you can crack it open with a stone or make a vent by cutting a hole in it.
You can also use 2 sheets of tin as shown in the photo.

HEAT SHEILD:
Half of a 4' x 8' sheet of 1/4" plywood cut down to 20" x 36" for the optional heat shield. Cost about $10.00.

PROTECTION:
2) Rolls heavy duty aluminum foil. Cost about $12.00.
COOKING GRATE:
4) 48" lengths of 3/8" rebar. You can use a sheet of expanded metal rather than rebar if you wish. Cost about $3.25 per 4' bar.

STRETCHER:
Uncoated fence wire or rabbit wire at least 14 gauge, 46 x 72". Do not use galvanized metal because it can give off noxious gases. Cost about $30.00 for a 50' roll. Some stores will cut it and sell it by the foot.
Stretcher Handles:
3) boards 1"x 2"x 6'. Cost about $2.00 each.
Stretcher Handle Ties:
100 bare wire loop ties, 6" each. Cost about $2.50.

DAMPERS:
2) pieces lightweight sheet metal, about 20" x 10" each or you can use old cookie sheet pans. They will go over the openings at each end of the pit. Cost about $15.00 if you go with the sheet metal.

OPTIONAL:
More rebar to pound from the top down into the ground to prevent the blocks from shifting. Cost about $20.00 for 6.
Mortar to lock the blocks permanently into place. Cost about $10.00.
Lightweight sheet metal for the lid, 44" x 60". Cost about $30.00.
Lightweight sheet metal for the heat shield, 30" x 48". Cost about $30.00
20) Bags (40 pounds each) premix concrete for a 3" thick bottom slab. Cost about $40.00.

TOOLS:
Fire extinguisher.
Wire cutters.
4' Level.
Hacksaw.
Hammer.
Chisel.
Utility stapler and plenty of staples.
Wheel barrow.
Steel drum, or old charcoal grill to start coals.
Flat Shovel.
Bow or Steel Rake
Good digital or oven thermometer.

BUILDING THE PIT:
Keep the pit at least 10' from buildings and overhanging trees in case there is a grease fire.
Start by clearing a base that is 4' x 5' by removing grass and prepare an all dirt or sand base at least 2" thick. You will need to discard some of it (if your building a temporary pit) when you are done because fat and meat drippings may get in the dirt. If needed, you can buy extra sand at a hardware store.
Make sure the ground is level.
If building a permanent pit, you would need to pour the concrete slab now if you so choose. You can still use a sand bottom with a permanent pit, however, it makes cleaning much more difficult since you would have to remove a few inches of sand after every few cooks and then replace it.
Stack the concrete blocks 4 rows high, 3 full lengths and then turn one block on each course, staggering the blocks so they overlap as in the illustration.
Don't put the top course of blocks on yet.
Notice that there is a block left out on each end of the pit so you can add coals or wood and rake them around.
Make notches in the current course of blocks with a hammer and chisel (as illistrated) deep enough to hold the rebar so the top course of blocks can lie flat on top.
Place the rebar in the notches on top of the fourth course of blocks.
Place the 5th. row of blocks on top.

THE STRETCHER:
To carry the hog and hold it in place on the pit, you need to build a stretcher. It consist of two poles for the stretcher bearers one on each side, and a wire mesh sling in between for the hog. Fence wire is heavier gauge and sturdier than chicken wire. You can use chicken wire, but it would be a good idea to use two layers.
Make sure the wire is not coated with plastic. Do not use galvanized, it can create toxins. The galvanize finish would burn off allowing the metal to rust anyway. You would just spend more money to possibly poison yourself.
Make the wire of the sling wide enough to rest on the rebar and hang over the outside edges of the pit by at least 1' on each side.
Attach two 6' lengths of 1" x 2" boards for handles with staples and reinforce them with the wire loop ties. Then lay another section of mesh over the top of the first and fasten it to one of the handles, but leave the other side unfastened. (See photo above)
Attach a handle to the open edge.
You then have a reversible stretcher so you can flip the hog.

THE HEAT SHIELD:
An optional heat shield can be made with a sheet of plywood cut down to 20" x 36". If you bank your coals to the sides and corners properly you may not need it, but again, unless you are an accomplished pitmaster, I recommend you have it on hand in case something starts to burn or overcook. The heat shield would go on top of the rebar and beneath the stretcher to shield the hog from direct heat. This size heat shield leaves space between the shield and the inner sides of the pit so hot air and smoke can rise along the sides of the shield to the top of the pit. You will remove it late in the cook when it is time to crisp the skin.
Cover the bottom of the shield with aluminum foil and staple it down. Don't worry, it won't burn unless you have a grease fire.
If the pit is to be a permanent structure, make your heat shield from sheet metal, preferably aluminum or tin.

THE LID:
If you use plywood for the lid, cover the bottom of the plywood with foil. If you prefer, you can use sheet metal or tin for the lid instead of plywood.