Properly spacing floor joists when framing an addition or whole structure is largely a factor of building codes. There are three basic measurements used for floor joist spacing. There are also several floor joist sizes and types used. The right spacing depends on the code requirements, as well as the type of structure it is and the weight it will bear. In this article, you'll start by understanding what floor joists are and why they are used. From there, the size and spacing options will be discussed.
Floor joists are horizontally oriented beams that make a frame on which to build a raised floor. Raised floors are superior to floors built on a slab, mainly for the reason that they provide a space through which to install other components. Electrical and plumbing lines, as well as an area for insulation, are more easily accommodated with a raised floor. Raised floors are also better able to withstand the constant wear and tear a floor experiences.
Integral Part of Framing
Structures are built able to bear a tremendous amount of weight. Floor joists, especially on the first floor, must be durable enough and properly spaced in order to function effectively. While they do not support the full weight of the home or other structure, joists are instrumental in ensuring that the building is soundly framed. Floor joists installed on second or third (or higher) levels double as ceiling joists for the level below. In buildings with basements, the first level of floor joists serves the same purpose.
Floor Joist Sizes
In the past, 2x4s or 2x6s were sometimes used as floor joists. This size is no longer acceptable when framing a structure. In general practice, 2x8s, 2x10s or 2x12s are used when framing a raised floor instead. The exact size necessary may be stipulated by the building code required for a particular structure.
The weightier the structure, the more durable the floor joists must be. For most homes, 2x8s are suitable. For bigger structures, manufactured I-shaped joists are used. These more closely resemble girders used for framing the largest buildings.
As with the joist size, the building code for your structure will stipulate the proper spacing between floor joists. The code itself is determined by the engineering requirements of a particular building.
Normally, floor joists are spaced 16 inches apart on center. This means from the center of one upright joist to the center of the next. Given that 2x8s are actually 1.5 inches wide, it works out to be 14.5 inches between each joist. With some structures, floor joists are required to be 12 or 24 inches apart on center.
To find the actual distance between the inside edges of each adjacent floor joist, subtract 1-¾ inches from either 12 or 24 inches. Still, when framing a raised floor, it's easier to think of floor joist spacing in terms of 12, 16 or 24 inches on center because each joist is positioned along the header according to its center point.
Apply a Polyurethane Finish to Laminate Floors FAQ
Is there a way to seal laminate flooring?
Laminate flooring can be sealed to make it more waterproof. Around the edges of the floor near the walls, use caulk to create a tight seal and help prevent moisture from water leaks.
It is also possible to seal laminate flooring with a clear polyurethane, which can be painted directly onto the floor with a paintbrush.
What can you put over laminate flooring?
If you want to cover up laminate flooring, there are a number of things you can put on top of laminate. It can be painted, for starters, but you can also place a new laminate floor over the existing one.
Tiles, foam, vinyl, and any number of flooring materials can be installed on top of laminate floors.
Can we apply varnish on laminate?
Varnish is not typically made to be applied to laminate flooring. A clear coat of polyurethane coating can be added, however, which has a similar effect to varnish.
What not to use on laminate floors?
Laminate floors are highly durable but they are not impervious to damage. Many household cleaners can damage laminate, as can exposure to moisture.
Avoid bleach, acetone, ammonia, and other harsh chemicals, as these can cause discoloration and damage. Moisture can cause floors to warp and laminate can become permanently damaged when exposed to liquid.
What will make laminate shine?
Simple cleaning and mopping should be enough to get laminate floors looking shiny again. Try mixing a few drops of standard dish soap in a gallon of water and mop laminate floors with this to bring out their luster.
Proper Spacing for Floor Joists FAQ
What is the rule of thumb for floor joists?
If you want an easy way to remember the proper spacing for floor joists, experts suggest the phrase half the span plus two. This means you should round the span of the floor joist to the nearest whole foot, divide this by two, and then add two to the total.
What is the most common joist spacing?
Most floor joists are placed 12 to 16 inches apart, typically no more than 16 inches apart as this could compromise structural integrity.
Can floor joists be 24 inches apart?
The standard for floor joist spacing is 16 inches apart. Anything more than this could compromise the structural integrity of the floor.
This standard is applied to all types of flooring and decking.
Are 2x6 OK for floor joists?
Floor joists can be in several different sizes. The most commonly used sizes for joists are 2x6, 2x8, 2x10, and 2x12.
Does it matter which way floor joists run?
Most floor joists in a home run just one way. This isn't necessarily due to some special reason but rather because all the joists are typically placed a one
However, floor joists often run opposite to the roof trusses. You don't want the trusses and the joist to go in the same direction, as this can put too much stress on the load-bearing walls.