Tips to Connect Wood Floor Joists to Cinder Block Walls

Lead Image
  • .25-3
  • Intermediate
  • 10-50
What You'll Need
Masonry nails
Masonry screws (Tapcon or Blue Screw)
Hammer drill
Safety glasses

Wood floor joists can be connected to cinder block walls. You will find you will simply need to know the tricks and tips that will help get the job done. This may be something you need to do because you are finishing your basement or redoing an addition with cinder block walls. Whatever the case may be, this is not a task that is impossible, but it will require the right tools.

Consider your Options

There are a few different options that you will have when it comes to connecting wood floor joists to concrete walls. You will find the least expensive way to do it is by purchasing masonry nails. They work great with connecting the concrete and the wood together. You may also want to try masonry screws. Usually, masonry screws are called blue screws or tapcons at hardware stores. When you choose a masonry screw, you will simply need to make sure that you have a screw with the ability to go all the way into a concrete wall. Usually, screws that are 1 3/4 inch or 1 inch will suffice.

Masonry Nail

If you have taken the masonry nail route you will need to make sure that you have the nail driven in between the blocks of the mortar. The most common mistake people make is screwing the masonry nails into the actual blocks themselves. When you drive the nail into the concrete block you can expect the nails to hold a lot better and the blocks will not run the risk of breaking.

Masonry Screws

blue masonry screws

Whenever you use masonry screws, begin by pre-drilling the holes the screws will go in. The diameter of the holes should be anywhere from 1/16 inch to 1/32 inch. When you are pre-drilling the holes, do it into the concrete block wall that the wood will be attached to. Whenever you are using the hammer drill you should go slowly and have patience. Apply pressure since you are drilling a concrete block, but make sure you are not doing all of the work. Simply apply enough pressure so you are backing up the drill as it does its job.


It is always important to remember safety whenever you are working on this type of project. Safety glasses are a necessity. You will especially want to use safety glasses whenever you are pre-drilling the holes for the masonry screws. Failure to take the necessary safety precautions could result in serious injury. You should also keep in mind masonry screws and nails should be the only thing you attempt to use for this task.