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The proper steel screw sizes for securing 3/4-inch plywood to the floor joists are #8, #10 and #12 screws. The number refers to the thickness of the screw. Each is available in lengths from 1 1/4 to 3 inches. Typically, the 3-inch variety is used to secure plywood subfloors.
How long should screws be for 3/4 subfloor?
You’ll want the screw to go about an inch past the plywood into the joist or underlying layer beneath it. So if your subfloor is 3/4 of an inch thick, any screw about 1 3/4 inches long will do the trick. If the plywood subfloor you’re placing is 5/8 of an inch thick, you need a screw about 1 5/8 inches long.
What size screws 3/4 plywood?
As a result, you’ll need a longer size wood screw to help secure joints at the end of boards. This is one of the most common types of construction I do in the shop — attaching a sheet of 3/4″ plywood to a carcass made of 3/4″-thick lumber. The #8 x 1-1/4 screw is perfect for bringing these two boards together.
Is 3/4 plywood OK for subfloor?
The recommended thickness of the plywood subfloor is governed by the spacing of the joists. Some experts suggest that 15/32-inch plywood should be standard if the underlying floor joists are spaced 16 inches apart or less, but slightly thicker 3/4-inch plywood should be used for joists spaced further apart.
How far apart should screws be on subfloor?
Generally, nails (6d ring or screw shank, or 8d common) should be spaced 6 inches on center along supported panel edges and 12 inches on center on the panels’ interior supports, or as specified on the construction drawings.
Is it better to screw or nail subfloor?
Using Improper Fasteners Using code-approved screws rather than nails is the best option for avoiding movement. If using nails for subfloor installation, stick with ring-shank nails; smooth nails may withdraw easier, leading to squeaks.
What screws to use on plywood?
For construction outdoors, such as an exterior stairway, zinc coated nails or decking screws should be used to attach plywood. These are designed to prevent rusting, which destroys the fastener.
Do you need to pre drill plywood?
Our first recommendation is to pre-drill if you are going to be screwing something into the edge of the plywood. The sheets of ply have a habit of separating when screws are inserted or even large nails. This process helps the layers of ply hold together and prevents it from chipping.
How do I know what size screw I need?
To measure the diameter of screws and bolts, you measure the distance from the outer thread on one side to the outer thread on the other side. This is called the major diameter and will usually be the proper size of the bolt.
Does it matter which way you lay plywood?
Ply should always be laid with the grain running across the joists, not along the joist, to maximise the strength. Laying them length ways down a joist will cause them to crack along the grain which could end up in serious injury and or damage. The smaller the gap between joists the stronger the board will be.
Does subfloor have to be tongue and groove?
For subflooring, you use tongue and groove plywood. The tongue and groove are only along the 8 foot edges. On the four foot edges, your seams will fall on joist tops, so no need for tongue and groove.
Which way do you lay a subfloor?
Flooring experts recommend installing flooring boards perpendicular to the floor joists in a house with a plywood subfloor.
What size plywood is best for subfloor?
The minimum thickness of plywood for subflooring is about 5/8 inch. Since it does not hold fasteners as well as plywood, OSB must be a little thicker, or at least 23/32 inch.
What type of plywood is best for subfloor?
Cheap and strong makes CDX plywood great for use as a structural panel such as a subfloor. Remember the letter grade of plywood only has to do with cosmetics and not strength. CDX plywood is just as strong as higher grades. CDX is a type of plywood that grades C, D or X.
How Far Can 3/4 plywood span?
h. Maximum span 24 inches where 3/4-inch wood finish flooring is installed at right angles to joists.
How far apart are plywood screws?
Use 8d common nails, spaced 6″ apart on edges and 12″ apart in the field. 1 1/8″-1 1/4″ panels. Use 10d common or 8d deformed nails, spaced 6″ apart on edges and 12″ apart in the field.
How far apart should wood screws be?
Appearance Counts. Though there’s no legal standard for screw spacing, an even spacing looks best. Don’t put the screws three inches apart on one board and four inches apart on the next. Pick a spacing and stick with it.
Can you use screws on subfloor?
For plywood, wood plank, or OSB subflooring, you can use either nails or screws to secure everything and attach it to the joists underneath. You don’t need to use either screws or nails on concrete subflooring because it is poured as a solid reinforced slab.
Should you screw down a subfloor?
The fastener you choose will certainly play a part in whether your floor squeaks or not. Screws, if driven properly, prevent creaking floors. A screw firmly holds the subfloor in place, which ensures a squeak-less floor for years to come.
Can I use screws in plywood?
Plywood is used in most construction projects. Putting screws into plywood is not difficult but care should be taken not to split the wood. There are many different types of plywood and screws. This procedure can be used with most combinations.
