Hot Tub Foundation Installation

Measure the base of your hot tub. Cut the 2 x 4 boards to create a frame large enough to surround the hot tub’s base. If the base of the hot tub is 6 feet square, then cut the 2 x 4s so they enclose a 6 x 6-foot area. Nail the 2 x 4s together to form a frame.

Place the frame for the hot tub in the place you plan to install it. Using the shovel, excavate the dirt inside the frame down 2 inches. The foundation should sit inside the ground, rather than on top of it.

Lay out the ½-inch rebar horizontally on the ground inside the excavated area inside the frame. Create a grid of 1-foot square boxes. In the example of a 6 by 6 frame, you’d need 10 pieces of rebar, cut to a length of 6 feet. Tie the rebar together at each point of intersection with the wire ties.

Slide the wooden blocks under the rebar, lifting the bars 2 inches off the ground. Place the blocks about 2 feet apart along each length of rebar. In the 6 by 6 example, you need between 12 and 16 wooden blocks to support the rebar.

Create the concrete according to the manufacturer’s instructions. Pour the concrete mix inside the wooden frame. Add the concrete mix slowly, using the wooden screed to force it down below the rebar grid. Fill the excavated area and bury the rebar completely with the concrete.

Smooth the concrete with the wooden screed or smoother. Lightly place the level on top of the screed while it lays on top of the concrete to see if the new concrete pad is even. Check it every foot or so. If it is not even, use the smoother to eliminate the slope in the concrete.

Allow the foundation to set completely before continuing with the hot tub’s installation. Wait at least four days to be sure the concrete is completely cured and ready to take on weight.