Take some time to determine where you want the fire pit to be. We were cautious not to put it under any trees or in an area that gets too much wind. Be thoughtful of where the best place is. You don’t want your new DIY fire pit to be a new fire hazard. This design is good at blocking the wind to prevent the risk of carrying the fire outside of the pit.
DIY Fire Pit – Site Preparation
Step 1: Decide that you want to build a fire pit out of boredom along with the desire to burn things.
Step 2: Find out whether your community fire department allows open burn pits. Some locations have restrictions or may require you to get a permit.
Step 3: Determine the location. We wanted a place that was amongst the trees to help break up wind, but not so close that a larger fire could burn the surrounding trees and their branches.
Here’s what you’ll need for your DIY fire pit. These items can be picked up at #HomeDepot and your local building/landscaping supply stores:
- River rock or stone of your choice. River rock is nice because it is smooth and has a nice finished look.*
- Rebar & tie wire. Home Depot has precut sticks that work quite well. We used four of them but this will depend on the size of the fire pit.
- Concrete mix.
- Mortar mix.
- Cement dye. Two bottles should cover it, but this depends on the amount of color and tint that you want the finished project to have.
- 2 – 3 five gallon buckets for mixing the cement and mortar.
- A grout-mixing or paddle attachment on your drill. You don’t necessarily need this, but it’s really handy.
- Mesh wire. Again, depending on the size of the DIY fire pit.
- Masonry trowel.
- We used 17 for the pit and 2 to rest our grill on.
- 3 – 4 pieces of ½” PVC tubing cut to 8”.
- Masonry screws. One box. We went with TapCon masonry screws which comes with the correct size masonry drill bit.
- Stainless fender washers. About 50 should work.
- Grout sponge. 1 – 2.
- Grout sealer. 2 bottles.
The not-so-fine print
*For the river rock, you’ll need to find a local landscaping supply company – someplace that sells bulk materials. If you don’t have a pick up truck, find a friend that does, offer to buy them lunch in exchange for the help and/or borrowed use of the truck, and tell them once the fire pit is completed they can come over and enjoy beers and bbq around it. What friend could say no to that? If they do, you should end this friendship anyway. Anyone who doesn’t want to enjoy beers and bbq around a fire is a heretic. You shouldn’t be associating with individuals such as this. Otherwise, you’ll be the person at the local landscaping supply placing each individual rock into the trunk of your car. Still possible, but more messy.
We used around 300 – 400 pounds of 6” river rock, however this is going to depend on the size of your project. It’s going to look like way more than you need, but I assure that this is going to be what it takes to build the fire pit. Also, having extra rock isn’t a problem. It’s always easier to have more than you need, than to not have enough. Plus, fitting them in place is a bit of a puzzle, so having extra pieces is almost necessary.
When you factor in all the exercise you’ll get from moving the river rock and concrete and mortar around, it will help save you money on gym memberships. Added perk.
Build your DIY Fire Pit
Step 4: We began by placing a stake in the middle of the location of soon-to-be fire pit and attached a piece of string to it. This allowed us to scratch a circle in the ground that would tell us where to dig out for the base. We decided that a 5 ft. base would be good. This is also the approximate exterior of the pit so going a little bit larger than you may originally think is important.
Step 5: Dig out the base. We dug down about 4 – 5 inches into the soil in the scratched out circle. We removed all rocks and roots that would get in the way then tamped down the soil to provide a solid, level base.
Step 6: Place some short lengths of rebar across the excavated area and ensure that they will ‘float’ in the middle of the concrete base. Be sure not to place them directly in the center as this is where the drains will go. Tie these pieces together with wire.
Step 7: Pour concrete base. When we poured this, we left the outside 10 – 12″ flat but floated a slope towards the middle where we created small drain holes using several 8” pieces of ½” PVC tubing. The drain holes are important because when it rains or you use water to put out your fire if you don’t provide a way for the water to escape, you’ll end up with a swampy mess in your fire pit.
Step 8: Once the concrete base has had a day or so to set, remove the PVC tubes and place cinderblocks (Concrete Masonry Units or CMU’s) around the perimeter of the base. This is why we wanted this area to be flat. We had first placed our blocks dry to make sure that we had the lay out and spacing correct, then we mixed up some mortar, spread it around the perimeter where the block was going to go, then placed the blocks in their proper locations.
Step 9: Affix wire mesh (chicken mesh) to the interior, exterior and top of the concrete blocks. The mesh is what the mortar and thin set will grip and bond to so it is important to make sure that this is thoroughly and neatly fastened. We used TapCon masonry screws and stainless fender washers to ensure that the mesh stayed in place. When installing the TapCon screws be sure to gently drill into the CMU’s because they are very easy to crack. Once the blocks crack, they will need to be replaced. We found that screwing into the solid ‘webs’ of the blocks worked quite well as opposed to screwing into the open sections, which are very weak and could cause the blocks to crack.
You’re Almost There…
Step 10: Apply tinted mortar to the interior of the fire pit. We opted for a rusty burnt color for the interior, which is available from Redi-Mix. See instructions on mix bottle. We used a thin set/grout paddle mixer attached to a ½“ drill to mix the mortar and applied it with a masonry trowel. We then let this set up for a couple days before moving on to the next step.
Step 11: Clean off any excess set mortar, then use thin set to apply river rock to the top and exterior. We purchased 6″ river rock from a local landscaping supply and cemented them to the wire mesh with thin set. This took a bit of time because the rock sometimes wanted to fall off so we had to prop some stones in place with sticks or use other rocks to support them while the thin set was curing.
It’s really starting to look like something now…
Step 12: After the river rock had a couple days to set up properly, we cleaned off any excess thin set with a sponge and prepared for the grout. We chose a dark brown grout but could have also used tinted mortar for this step as well. Tile grout may not be the best choice of materials because it shouldn’t be used for such large gaps, but we really liked the color and at this point were ready to wrap up the project. We used grout floats and sponges to force the grout into as much of the crevices as humanly possible and create a smooth transition between the rocks. Grout is what keeps the stone in place, so the better job you do on this step, the better your project will come out.
Step 13: After the grout has set, use a wet sponge to remove any excess grout and haze from the stone. Once the surface is completely clean and dry, apply a grout sealer to the top and exterior (not the mortar interior).
Step 14: We then did a little landscaping around the pit using extra river rock and stone from our property. This helped create a sitting area around the fire pit.
Finally, you can burn something!
Step 15: Start a fire, crack a refreshing beverage of your choice and celebrate your new fire pit. Congratulations, your neighbors will soon be flocking to your house and asking you to build one for them.
DIY Fire Pit – Hindsight notes:
- Using tinted mortar may have been a better option on our DIY fire pit as the grout has faded. Now our chocolate brown grout is looking a bit more brownish-purple.
- Fires seem to have enough ventilation to burn reasonably well, however adding some ventilation holes around the base of the wall may allow the fire to breathe better. This could be done with some small sections of galvanized pipe. Make sure that these are long enough to extend from inside to the exterior of the fire pit. Place them a couple inches above the concrete base so standing water doesn’t become an issue.