How to Put Supports Under a King-Size Bed

The spaciousness of a king-size bed comes with one serious disadvantage: its wide, heavy, soft mattress often starts to sag sooner than their smaller counterparts.

This is especially true if your bed is a gathering place for the whole family. A mattress designed for two adults takes a lot of damage if it has to support two adults, three kids and the family dog. You can shore up the underside of your mattress with a few well-placed cinder blocks. However, a more permanent solution can help distribute the weight and add years to the life of your bed.

Measure the distance between the underside of your mattress and the floor.

Cut your beams so that they are both as wide as the distance measured earlier. You can save money by waiting to buy them until after you've completed the measuring. That way you won't buy a 10-inch wide beam when a 7-inch beam will do.

Find the center of the 80-inch beam. Cut a notch in the 2-inch wide side using your power saw. Cut the notch 1-1/2-inches wide and half as deep as the beam is wide. Repeat this with the 76-inch beam.

Slide the two beams together in a cross shape, nesting them at the notch like a pair of Lincoln Log toys.

Slide the cross underneath your mattress. Depending on the structure of your frame, you may need to lift the bed and set it down on top the support beams.

Things You Will Need

  • Measuring tape
  • Wooden beam, 2 inches by 80 inches
  • Wooden beam, 2 inches by 76 inches
  • Power saw

Tip

  • The dimensions given here are for a standard king mattress. California king mattresses need beams that are 72-inches and 84-inches long, respectively.

About the Author

Jake Wayne has written professionally for more than 12 years, including assignments in business writing, national magazines and book-length projects. He has a psychology degree from the University of Oregon and black belts in three martial arts.