Plywood Thickness: Complete Guide [Including Charts]

Plywood is a common wood panel used for a multitude of industries and purposes. Its thickness often determines how it will be used. So, if you’re wondering what plywood thickness is best for your project, we’re here to help.

Plywood is typically manufactured in thicknesses from 1/8” to 1-1/4”, with some up to 2” in thickness. Due to the frequency of use for construction, cabinetry, furniture, and other projects, 1/4″, 3/8’, 1/2″, 5/8”, and 3/4″ are the most common and readily available thicknesses. Other thicknesses may be ordered from suppliers, and unique thicknesses ordered from some mills for special projects.

In this guide, we identify the nominal and actual thicknesses of plywood to make it easier to select the thickness you require. We also examine the thicknesses available for different grades and types of plywood used for different applications. Plus, we discuss the thickness tolerances of plywood, how to measure the thickness, and standard dimensions of plywood. Our aim is to provide you with a definitive guide for selecting the best plywood for your project.

Plywood Thickness

Actual vs. Nominal Plywood Thickness

Plywood typically is manufactured using odd numbers of veneer layers ranging from 3 to 11 ply, with some having as many as 21 or more plies. The top and bottom plies are often thinner than the inner layers and determine the panel’s grade quality.

The inner or core layers are usually all the same thickness. For example, 3/4” ply could have 7 layers with the five inner layers each being 9/64” thick and the top and bottom each being 15/508”. Different thicknesses can also have the same number of plies, with 3-ply commonly available in thicknesses ranging from 1/8” up to 1/2″.

Plywood is available in different grades and types which can affect the nominal and actual thickness of a panel. Depending on the type or grade the common thicknesses range from 1/8” to 1-1/4”, with thicker sheets available upon request from some manufacturers.

The thickness can also vary if the plywood is non-sanded or sanded, plus moisture content and humidity can cause the veneer plies to swell. The actual panel thickness is typically about 1/32” less than the nominal thickness.

The Table below identifies the nominal and actual thickness of plywood available from different North American mills. It should be noted, though, that not all are readily available at most suppliers, nor are they all manufactured by every mill.

Plywood Thicknesses Nominal vs Actual
Nominal ThicknessActual Thickness
inchesmminchesmm
1/8”4mm3/32”3mm
3/16”4.5mm5/32”3.97mm
1/4”6.35mm7/32”5.56mm
5/16”8mm9/32”7.14mm
11/32”9mm5/16”7.94mm
3/8”9.525mm11/32”8.7mm
7/16”11mm13/32”10.32
15/32”11.9mm7/16”11.1
1/2”12.7mm15/32”12mm
19/32”15.1mm9/16”14.3mm
5/8”16mm19/32”15mm
23/32”18.25mm11/16”17.5mm
3/4”19.05mm23/32”18.2mm
7/8”22.5mm27/32”22.2mm
1”25.4mm31/32”24.6mm
1-1/8”28.575mm1-3/32”27.78mm
1-1/4”31.75mm1-7/32”30.96mm

Standard Plywood Thickness Chart

Standard Plywood Thickness Chart

Plywood is manufactured in numerous thicknesses and is typically identified by its nominal thickness, which can vary by 1/16” or more from panel to panel. The thickness can also be affected by humidity as wood will swell with moisture content.

The standard thickness of different types of plywood commonly manufactured is identified in the Table below. Some thicknesses, though, have been rounded up or down slightly as they were close but not exact. However, it should be noted that not all are stocked by every supply store, so may be difficult to find.

Additionally, non-standard thicknesses are available from some mills by special order depending on the volume requested.

Plywood Type1/8”1/4”5/16”3/8”1/2”5/8”3/4”1”1-1/8”1-1/4”
SoftwoodXXXXXXXXX
HardwoodXXXXXXXX
ACXXXXXX
BCXXXXXX
CCXXXXXX
CDXXXXXXXXX
WBPXXXXXXX
RTDXXX
SandedXXXXXXXXX
Pressure-TreatedXXXX
Construction GradeXXXXX
Furniture PlywoodXXXXXXX
Shop GradeXXXXXXXXXX
Baltic BirchXXXXXXXX
AircraftXXXXXXX
Marine BoardXXXXXXXXX
Tropical PlywoodXXXXXXXXXX
Lumber CoreXXXXXX
Oriented Strand Board (OSB)XXXXXXXX
Particle BoardXXXXXXXXX
Luan PlywoodXX

Common Plywood Thicknesses

Common Plywood Thicknesses

Plywood is commonly available in thicknesses ranging from 1/8” to 1-1/4”, with some as thick as 2”. The availability and range of thickness, however, often depend on the grade and type of plywood, and on your location. Below, we discuss the common thicknesses typically available for different grades or kinds of plywood.

Some mills produce a full range of thicknesses while others don’t. Special orders of unique thicknesses can also be manufactured depending on the volume required. It is also possible to laminate panels of different thicknesses to achieve the desired thickness for small orders. Much, though, depends on economics.

Softwood

Softwood plywood is used for numerous furniture, cabinetry, construction, and other projects and is usually the most readily available. The panels are manufactured in most thicknesses between 1/8” and 1-1/4”, but are more commonly available from local suppliers in 1/4″, 3/8”, 1/2″, 5/8”, and 3/4″ thicknesses.

Hardwood

There are different kinds of hardwood plywood with some having a hardwood veneer on one or both faces over a softwood core and others with a hardwood core. The latter is more costly, but both are usually topped with A or B-grade veneers while the bottom may be A, B, or C-grade.

The type of panel often determines its use, but they are used for cabinetry, furniture, decorative panels, sports equipment, and musical instruments. Hardwood plywood is also used in the fabrication of watercraft, automobiles, and aircraft. Thicknesses range from 1/8” to 1”, but it is usually readily available in 1/8”, 1/4″, 3/8”, 1/2″, and 3/4″ dimensions.

Sanded

Some plywood is sanded smooth on one or both faces and is known as Good One Side (G1S) or Good Two Sides (G2S). It is commonly hardwood, but a limited selection of softwood is also sanded. G1S and G2S are frequently used for furniture, cabinetry, paneling, or other visual purposes.

The top is usually A or B-grade veneer and the back is A, B, or C-plugged veneer. It is available in numerous thicknesses from 1/8” to 1-3/16”, but is most often found in nominal thicknesses of 1/8”, 1/4″, 3/8”, 1/2″, 5/8”, and 3/4″.

Pressure-Treated

Pressure-treated plywood is used where the wood may be exposed to moisture or in contact with the ground and is usually exterior-grade construction plywood. The treatment typically makes the wood more resistant to delamination, mold, mildew, and rot.

It is often used for foundations, wall sheathing, decks, fences, and other outdoor projects. This plywood is commonly available in 3/8”, 1/2”, 5/8”, and 3/4″ thicknesses.

Construction Grade

Construction grade, sheathing, or structural plywood is strong, durable, and less expensive than other grades. It is commonly finished in C or D-grade veneer and not sanded, and used to sheath floors, walls, and roofs.

Due to voids and knot holes, this plywood shouldn’t be left exposed to moisture for too long. It is commonly available from suppliers in thicknesses of 1/4″, 3/8”, 1/2″, 5/8”, and 3/4″.

Furniture Plywood

There are numerous types of high-quality plywood that fit into the furniture plywood category. It can be hardwood or softwood plywood with either a softwood or hardwood core. Plus, it can have either hard or softwood veneers on top and/or bottom.

Furniture plywood is usually AA, AB, AC, BB, or BC graded panels due to their better appearance and smoothness, and greater strength. Furniture plywood is commonly found in thicknesses of 1/8”, 1/4″, 3/8”, 1/2″, 5/8”, and 3/4”.

Shop Grade

Shop grade plywood usually refers to panels that were damaged in shipping or at the mill, or factory seconds. It can’t be sold as graded plywood but may be mill-certified. Depending on the usable area of the panel, it can be used to make cabinetry, furniture, beams, toys, crafts, shipping boxes or strapping, or numerous other items. Shop grade is available in all common thicknesses.

Baltic Birch

Baltic birch is usually manufactured of plies of A or B-grade birch layers that are 3/64” thick, making it a strong, durable hardwood plywood with no voids. It has excellent load-bearing capabilities and is easy to finish.

It is often used for cabinetry and furniture making and is well suited for laser cutting and engraving. It is commonly available in thicknesses ranging from 1/8” to 3/4″, but thicker panels up to 1-1/8” can be found.

Aircraft

Aircraft plywood is strong, highly durable but lightweight and resistant to heat and moisture. The plies are either mahogany or select types of birch, spruce, or basswood. The layers are also thinner than standard plies which improves strength and flexibility.

It is often used to build aircraft, watercraft, and heavy-duty industrial or machinery furniture. It is available in 1/16”, 3/32”, 1/8”, 3/16”, 1/4″, 5/16”, 3/8”, 7/16”, 1/2″, 5/8”, and 3/4″.

Marine Board

Marine plywood is a high-quality fungal-resistant solid A or B-grade plywood that can withstand humidity, moisture, and full emersion without delaminating. It is used to manufacture boats, ships, outdoor structures, outdoor furniture, and other items that need to withstand exposure to moisture.

Marine plywood is commonly available in 1/8”, 1/4”, 3/8”, 1/2”, 5/8”, and 3/4″. Other unique thicknesses may be found or ordered.

Tropical Plywood

Tropical plywood is manufactured from hardwood species such as ebony, mahogany, and teak from Asia, Africa, and South America. All veneer layers are of tropical wood, giving the plywood better structural performance characteristics and hardness than other plywood.

It is graded with the same system as other plywood but has greater appearance qualities and value. It is available in a dozen or more thicknesses between 1/8” and 1-1/2”.

Lumber Core

Lumber core or blockboard plywood is manufactured using strips of soft or hardwood laid side by side so their grain alternates for the core with a thin layer of veneer on the top and bottom. It is a strong, durable, inexpensive plywood with very good screw-holding ability, and is available in both interior and exterior panels.

Interior panels are typically used for doors, wall panels, shelving, partitions, and furniture, while the exterior is used to sheath floors, walls, and roofs. It is commonly available in 1/2”, 5/8”, 3/4″, 1”, 1-3/16”, 1-3/8”, 1-37/64”, 1-3/4”, and 2” thicknesses.

Oriented Strand Board (OSB)

OSB is manufactured with up to 50 layers of thin flakes or strands of soft and hardwood that are soaked in glue, heated and compresses to the desired thickness. The panels are used for subflooring, wall and roof sheathing, packing and shipping crates, dog houses, and other purposes. Although available in thicknesses from 1/4″ to 1-1/8”, most suppliers carry it in 1/4″, 3/8”, 1/2″, 5/8”, 3/4″, and 7/8” thicknesses.

Particle Board

Particle board is manufactured from wood fiber or particles and adhesive. It is commonly used for cabinetry, furniture, signage, packaging, flooring, and other dry location uses. It is heavy and dense, but brittle. It is available in 1/4″ through 1-1/2” thicknesses, but is most commonly found in 1/4”, 1/2″, and 7/8” dimensions.

Luan Plywood

Luan plywood is a tropical plywood often used for flooring underlayment, cabinetry, and furniture making. It is a lighter-weight hardwood plywood with good strength qualities. It is commonly available in 1/8” and 1/4″ nominal thicknesses.

Common Plywood Thickness for Different Applications

Plywood for Structural Applications

Plywood is manufactured in numerous thicknesses between 1/8” and 1-1/4”, with some as thick as 2”. The thickness and number of plies, along with the type or grade generally determine the strength, purchase price, and applications for which it may be used.

So, while you could use Baltic birch or marine plywood for sheathing a roof, construction grade is significantly less expensive and designed for that purpose. Below, we identify and discuss the thicknesses of plywood commonly used for different applications.

Structural Applications

The thickness of plywood for structural applications generally depends on the spacing between support members like joists, studs, and rafters or trusses. Additionally, the type of loads, finish materials, and personal preference can also affect the choice of thickness. Always check local codes to ensure compliance.

Plywood used for subflooring is usually 5/8” for 12” and 16” O.C. joist spacing and 3/4″ for 19.2” and 24” O.C. spacing, with 7/8” thick for heavier floor finishes. Wall sheathing thickness for 16” O.C. stud spacing is commonly 1/2″ while 3/8” panels can be used for 24” O.C. framing. However, 5/8” is commonly used but 3/4″ plywood may be required.

Roof sheathing is also affected by slope and environmental conditions. The thickness for 16” O.C. supports is commonly 1/2″ or 5/8” and 3/4” or 7/8” for 24” O.C. spaced supports.

Non-Structural Applications

Plywood thicknesses for non-structural applications such as decorative ceiling or wall panels, signage, or other purposes vary based on support, aesthetics, and design requirements. Non-structural plywood is usually visually better looking and may be lighter weight, and is often more expensive.

Decorative wall panels often range from 1/4″ to 1/2” thick and free-hanging ceiling panels from 1/2″ to 3/4”. However, depending on the spacing of supports or gluing, thinner panels may be used too. Acoustic panels commonly use 5/8” and 3/4″ plywood, while partition panels may range from 1/4″ to 3/4” depending on framing.

Furniture and Cabinetry

Plywood for Furniture

Furniture and cabinetry often use plywood of various thicknesses depending on the purpose. Structural partitions or panels range from 3/8” to 3/4″ depending on load expectations. Interior non-structural partitions may be 1/8” to 3/8” while mounting or fastening supports are often 5/8”.

Desk or table tops range from 3/4″ to 1-1/2” or even 2” in thickness depending on supports. Wardrobes, dressers, and cabinets may use 1/8” or 1/4” thicknesses for backs, side, and door panels, but 3/4” for shelving and 1/2″ or 5/8” for drawers.

Plywood molded or used for chairs or toys typically ranges from 3/8” to 1-1/4”. However, other thicknesses can be used too.

Flooring

Sub flooring plywood is usually 5/8” to 7/8” thick depending on support spacing and expected loads. Plywood used for engineered wood flooring commonly ranges from 1/8” to 3/4″ – the thicker the ply, the greater the cost.

Plywood designed specifically for finished flooring typically has a thicker top veneer of higher visual quality. The thicker veneer allows for greater wear and the possibility of sanding and refinishing once or twice in the future.

Subflooring that will be left exposed as a finished floor is often 3/4″ G1S sanded, making it easier to paint or stain, and clean.

Roofing

Plywood for Roofing thickness

The spacing of roof trusses or rafters differs with the span, load, and slope, which can also affect the thickness of plywood sheathing. Sheathing for roof supports spaced 16” O.C. or less is commonly 1/2″ or 5/8” while 3/4” is typically used when supports are 19.2” and 24” O.C. apart.

For light loads and rafters spaced 12” O.C. or less, 3/8” plywood can be used if it’s code compliant. A stronger roof decking will improve the roof’s longevity.

DIY Projects

The thickness of plywood used for DIY projects greatly depends on the project, budget, and if it is structural or decorative in design and usage. Most supply stores carry several types or grades of plywood from 1/8″ through 3/4″ thickness.

So, unless a specialty type or thickness is required, most DIY projects are completed using 1/4″, 3/8”, 1/2″, 5/8”, and 3/4″ plywood. If thicker pieces are required, many DIYers find it cheaper and quicker to glue and clamp two or more thicknesses together to achieve the desired dimension.

Outdoor Projects

Outdoor Projects

Outdoor projects will use similar thicknesses of plywood to DIY projects but often different types of material rated for exterior use or even pressure-treated. Privacy fence panels may be 1/4″ to 1/2” while table tops, countertops, and chair slats and seats may be 5/8” or 3/4″.

Storage sheds, playhouses, and other projects will vary depending on framing materials and spacing but are commonly 1/2″, 5/8”, and 3/4″ in thickness.

Plywood Thickness Tolerance

The thickness variability or tolerance typically refers to the differences in thickness between plywood panels of the same quality, composition, and grade. They could even be in the same bundle and manufactured in sequence. The thickness difference can be caused by moisture content, veneer and glue thicknesses, temperature, and press consistency.

The difference between two utility or graded softwood panels can be 1/32” while hardwood or furniture-grade panels may vary 1/64” in thickness. The higher the quality of material, the greater the consistency of thickness.

The ISO (International Organization for Standardization) identifies the dimensional tolerances for plywood to ensure consistency in thickness (ISO 9426) and moisture content (ISO 16979), as well as other dimensions and characteristics.

How to Measure Plywood Thickness

Plywood thickness can affect butt joints, dados, and other joints or seams. The nominal thickness of plywood is commonly 1/32” greater than its actual thickness. However, that is not necessarily true for each sheet of the same grade and type of plywood.

Edge measuring may show a greater discrepancy if you have a good eye, but the best way to accurately measure the thickness of plywood is with calipers. Digital and dial calipers are easier to read, but spring joint calipers will work too, but aren’t as easy to read.

Standard Plywood Sheet Sizes and Dimensions

Plywood Sheet Sizes and Dimensions

Plywood sheets are available in different thicknesses as well as a variety of lengths and widths.

The dimensions often depend on the type and grade of the panels. The most common sizes are 4×8, 4×4, 2×2, 2×4, 4×9, 4×10, 4×12, 5×10, and 5×5.

Other dimensions, such as 3×6, 3×7, 3×8, 4×6, and 4×7 are less common but still considered standard.

Larger lengths and widths can be ordered but are usually limited by the length of the flatbed available for delivery.

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