How to build a concrete boat ramp?

The article aims to answer the question “How to build a concrete boat ramp?”. It will also discuss the tools you may need and how to build a concrete ramp over already existing stairs.

How to build a concrete boat ramp? 

  • Measure the area you want to cover. Ensure there is enough room for a tow vehicle and a trailer to maneuver into the ramp area and then back down into the ramp area. 
  • Only a 15 percent slope is ideal for a boat ramp’s slope; when the ramp is covered in algae and other debris from the sea, a higher grade will create perilous situations. If the ramp is sloppy and the grade is too steep, the weight of a boat can pull a truck into the water.
  • The design of your ramp should be tailored to the size and function of your boat. A 12-foot ramp (from the water line to the end) is enough for small boats. Allow at least 20 feet of ramp below the waterline for large boats or public ramps with considerable usage.
  • The design of your ramp should be tailored to the size and function of your boat.
  • Allow at least 20 feet of ramp below the waterline for large boats or public ramps with considerable usage.
  • Create the proper slope for your concrete slab with a backhoe and smooth the surface. The likelihood that a concrete slab will crack or crumble under the weight of heavy vehicles increases if it is placed on top of ridges, mounds, or drop-offs. 
  • The gradient should be twice as high above the waterline as it is below it. This does two things. It is imperative that concrete slabs be poured on the same angle grade as they will be put to avoid stress fractures from a change in grade, as well as to provide tow vehicles the best leverage and easiest access to launch or retrieve boats.
  • Lay 60-grade rebar every 4 inches down the length and diagonally. On all sides of the ramp form, leave a 6-inch lip, and position your reinforcing bar so that it is at least three inches from your finished concrete.
  • Use a trowel to level the surface of the concrete after it has been poured into the form. Allow it to air dry for a few hours. Get rid of the 2-by-6 side pieces and the braces.
  • Bulldozers can be used to push the slab into the water, or a crane can be used to hoist and lower the slab into its final location, as needed.

What tools do I need to build a concrete ramp?

  • A fine-bristled broom or wood concrete float
  • compactible gravel
  • 3/4-inch exterior-grade plywood
  • 2×4 timber
  • 60-grade rebar
  • Bulldozer
  •  wood screws
  • Stakes
  • Concrete mixing tools
  • Form release agent (vegetable oil, for example) 
  • Isolation board (if necessary)

What considerations do I need to keep in mind to build a concrete ramp?

  • It’s essential that you plan out your project before you begin building a ramp. 
  • Concrete, unlike wood, does not allow for alterations in the middle of the project. You must first decide what you want to accomplish, and then devise a plan to get there.
  • One inch of drop per 12 inches of run is the highest ratio you can have on a ramp. 
  • A ramp steeper than this will make it difficult to ascend and descend, especially if it is wet or ice. Run your ramp a little further out than to have to deal with a risky ramp.
  • It is recommended that the concrete be at least four inches thick, but for light use, you can get away with just two inches of concrete. Digging at ground level is required so that the concrete ramp’s bottom border is truly buried in dirt.
  • In contrast, you don’t want to be pouring more than 12 inches of concrete. With more than 12 inches of concrete required, use rock, gravel or compacted earth to fill in any empty space, so you don’t have to use as much of the material. 
  • Filler should be kept at least four inches away from the ramp’s edge, so that it doesn’t weaken its structural integrity.

How to calculate the concrete I need for a concrete ramp?

The simplest technique to figure out how much cubic feet of concrete you’ll need is to do a basic arithmetic problem. A rectangular slab rather than a triangular cross-section should be used when calculating volume. 

Multiply the length, breadth, and height to obtain this volume (or thickens). To avoid confusion, make sure that you’re only doing this in inches or feet.

You’ll get a volume boost that’s two times what you’d get from the finished ramp. The volume of your ramp can be determined by simply dividing the answer by two. 

To acquire cubic feet, multiply your answer by 1,728 if you used inches as your unit of measurement. Cubic feet divided by 27 equals cubic yards.

Depending on where you buy it and what kind you buy, concrete comes in 60- and 80-pound bags. The bag should have a varying volume as well. 

Keep in mind that this volume is only an approximation, as the actual volume will depend on how you mix it. To be on the safe side, buy a few extra bags.

How to build a concrete ramp over existing stairs?

The volume of the steps can be subtracted from the total amount of concrete needed when pouring a ramp over an existing staircase. 

In other words, the method remains the same, as the ramp cannot be constructed at the same slope as the steps. It must still rise and run at the same rate as before.

To pour the concrete, you will need a mold or form. Wood stakes are used to hold plywood panels in place for the form. While the concrete is hardening, the form holds it in place so that you may finish the project without it looking like your kids made it out of mud.

In order to allow your ramp to sink four inches into the earth, you’ll first need to dig out the end of the downhill section. 

In this design, the ramp’s top surface is designed to be flush with the ground, allowing you to easily transport heavy objects up and down the ramp. The bottom of your ramp will break if you don’t dig into the ground first.

Remove the sod as you prepare the ground for the ramp’s base. Grass roots die when they are removed, creating a hole in the ground. You don’t want a void under your ramp, but you do want solid ground.

The plywood sides of the ramp should be cut to the exact height that you want. It is important that you cut this to the correct length since you will be using it as a guide to level and smooth the slope. 

Set up the plywood form and secure it to the ground with wood stakes. The weight of the concrete will try to drive these anchors outwards, so they must be sturdy. Plywood is fastened to the stakes with nails.

Conclusion

While it is easier to build a concrete ramp than a stone or compressed soil one, it is more complicated. Precast concrete boat ramp slabs are lifted into place after they have been pre-poured. A concrete boat ramp can be built by anyone, but it requires a lot of heavy machinery and careful design.

After placing compacted gravel on the ground, you build the wooden form over which you pour the concrete, and finish the surface so it is level with the top of the form. With plywood cut at an angle along the top, build the sides of the form to produce the ramp’s slope.

Frequently asked questions (FAQS): How to build a concrete boat ramp?

How to build a concrete boat ramp? 

Measure the area you want to cover. Ensure there is enough room for a tow vehicle and a trailer to maneuver into the ramp area and then back down into the ramp area. 

Only a 15 percent slope is ideal for a boat ramp’s slope; when the ramp is covered in algae and other debris from the sea, a higher grade will create perilous situations. If the ramp is sloppy and the grade is too steep, the weight of a boat can pull a truck into the water.

How to build a concrete ramp?

A 4 inch layer of compacted gravel should be laid down as a foundation for the ramp. Using 3/4-inch plywood and 2×4 lumber, construct the ramp form. The side parts must be identical and sit level on top of each other to ensure this is the case.

The form should be staked and braced, and the level should be checked.  Attach a piece of isolation board to the juncture if either end of the ramp will meet a sidewalk, slab, or other permanent structure.

How to build a concrete ramp over existing stairs?

The volume of the steps can be subtracted from the total amount of concrete needed when pouring a ramp over an existing staircase. In other words, the method remains the same, as the ramp cannot be constructed at the same slope as the steps. It must still rise and run at the same rate as before.

To pour the concrete, you will need a mold or form. Wood stakes are used to hold plywood panels in place for the form. While the concrete is hardening, the form holds it in place so that you may finish the project without it looking like your kids made it out of mud.

Bibliography 

The plywood. How to Pour Concrete Ramp. Retrieved from: http://theplywood.com/pour-concrete-ramp

Stanley Goff. How to Pour a Concrete Ramp Onto a Slab. eHow. Retrieved from: https://www.ehow.com/how_7838013_pour-concrete-ramp-onto-slab.html