Once everything is laid out, we then cut the shape out with a jigsaw and use it as a template to mark the other seven pieces and cut them all out, being careful to get them all as close to the same as we can. There is a small notch for the coping where that top-line meets the slope that is 1.25' tall and 1.75' deep. Next, we measure the back side to 2' 11.25' up from the bottom and then square that line across until it meets the curve we just drew. (This part is easier to see and understand if you watch the video from Step One.) We'll then measure a 6' length of string and tie a pencil to the end and use it to draw the radius on the wood. Once we have it marked, we'll put in a screw and then tie a string to it. Since 2x4s are 3.5' wide, this will give us a 6' radius slope. To lay them out, we start by putting two sheets side by side on the ground and marking the pivot point which is 6' 3.5' from the bottom and 2' in from the side. These are cut from 3/4' plywood and we can get two transitions from one 4' x'8' sheet. For this ramp, we're building four different quarter pipes and each one has a transition on each side. The first bit of construction is to layout and cut the sloped transitions that make up the sides of the ramp. To help keep it level for a long time we put a 3-4' thick layer of gravel underneath each of the footings.įor the rest of the ramp, we'll put 2' thick concrete pavers every 4 feet along the length of the ramp. We use a line level to ensure all 4 corners are level with each other, as well as square and evenly spaced.īecause the ramp is heavy, the foundation will settle a bit over time. Because our yard slopes downhill, the ones at the top get buried quite a bit and the ones at the other end are above ground. We start by laying out exactly where it will go in the yard and then use Concrete Footings (12' x 12' x 8') and put one at each corner. In our case, our yard is neither flat nor level so we had to fix that.

It's important that the ramp sits on level ground, so in a perfect world, it would sit either on a flat concrete pad or at the least on a wide level space. Whatever the exact size of your ramp, you're going to need a flat piece of ground to put it. The ramp we're building is 3 feet high, 12 feet wide and 24 feet long.

Backyard mini ramp bmx