What size lumber is used for ceiling joists?

Although 2-inch by 6-inch lumber is used most often in ceiling construction to support 5-foot by 8-foot sheetrock — the material commonly used for ceilings — other sizes of lumber may be used, such as 2-inch by 4-inch and 2-inch by 8-inch lumber.

What size should ceiling joists be?

Though there is no standard joist size for the ceilings in all buildings, most average homes use ceiling joists in a board size of 2-by-6 inches. The range of joist sizes used in homes varies though, between 2-by-4 inches and 2-by-12 inches.

What is the maximum span of a 2×6 ceiling joist?

The maximum distance a 2×6 can span, according to the 2018 IRC, for a floor joist, is 12′-6”, ceiling joist 20′-8”, rafter 18′-0”, deck board 24”, deck joist 9′-11”, deck beam 8′-3”, and 6′-1” as for header. Always check the codes for determining factors or consult a Structural Engineer.

What kind of wood is used for ceiling joists?

Kiln-dried Douglas fir wood presents the number one choice for building a rafter-styled roof in a wood frame house.

Can I use 2×4 for ceiling joists?

A 2×4 can span a maximum of 6′ 7” when spaced 16” apart and used as a floor or deck joist. When used as a ceiling joist or a roof rafter, a 2×4 can span up to 7′ 3” spaced at 16”, and 6′ 4” when spaced 24” apart. Due to the small spans of 2x4s, they often are not used in horizontal load-bearing capacities.

Can you span 16 feet with a 2×6?

2-grade 2×6 joists can span up to 10 feet 9 inches from beam to beam when spaced the standard 16 inches apart with a maximum live load of 30 inches per square foot. In comparison, No. -1 grade lumber can span slightly further to 10 feet 11 inches under the same parameters.


What size of timber is used for ceiling?

Only selected boards of uniform width and thickness shall be used for wooden ceiling. Minimum width of selected board shall not be less than 100mm. The maximum width of selected board shall not be more than 150mm. The maximum length of selected board shall not be more than 180 cm.

What size ceiling joist do I need for a 12 foot span?

R802. 4 Allowable Ceiling Joist Spans

CEILING JOIST SPACING (inches) SPECIES AND GRADE DEAD LOAD = 5 psf
Maximum ceiling joist spans
(feet – inches)
12 Douglas fir-larch 13-2
Douglas fir-larch 12-8

What size beam do I need for an 18 foot span?

Wood beam size for a 18 foot span:– as per general thumb rule, for a 18 foot span, size of wood beam or lumber joist should be 2×12 which placed at 16″ apart from centre used for residential building or projects or construction in which depth of section of beam is 300mm (12″) and width of beam is 50 mm or 2″.

How far apart can ceiling joists be?

Ceiling joists are usually installed either 16 or 24 inches on center, which means roughly 16 or 24 inches apart. Once you’ve located the first one, the others are easier to find. If you only need to know which direction the joists run, access the attic and take a look.

How much weight can a 2×4 ceiling joist hold?

A 2×4 can support up to 1,000 pounds vertically. This dimensional lumber is the most common material used to frame interior and exterior walls on a home. When used as wall studs, 2x4s are typically grouped to create a wall, spaced 16 inches apart.

Can you use 2×6 for roof rafters?

2×6 shed roof rafters are enough for nearly any type of shed a homeowner wants to build. While a 2×6 might be nearly double the cost of a 2×4, you can likely space the 2x6s further apart, negating the added expense of increasing your lumber width.

Are ceiling joists hard or soft wood?

Structural joists and planks: The largest of the lumber grades, this classification is for softwood lumber between 2”x5” and 4”x18”. This grade is used for ceiling joists, rafters and floor joists. They’re graded from select structural to No. 1, 2, and 3.

How far can a 2×4 span without sagging?

You can calculate the typical span by multiplying the depth of the lumber by 1.5. For 2x4s, this would equal 6 feet, but that is only a general calculation. When used as floor or deck joists, the maximum span for a high-grade 2×4 is around 6′ 2” for 16” spacing using Southern Pine depending on the other factors.

Can I use 2×4 for ceiling drywall?

2×4’s at 16” o.c. spanning 18′ will not work. They’ll sag under their own weight, much less adding a layer of gypsum board. The Code requires a minimum live load of 10 lbs. per square foot for limited storage (maximum clear space between new floor joists and roof joists of 42”) and 20 lbs.

How do you install a 2×4 ceiling joist?

How To Install Weight-Bearing Ceiling Support – Reinforcing Sheetrock to …

How do you reinforce 2×6 ceiling joists?

Strengthening Attic Joists for Live Loads by Sistering

In the case of 2 x 6 joists, you can pair them up with additional 2 x 6 joists by nailing them together, side by side. The best-case scenario is to run the sisters the entire length of the existing joists so that you have two additional resting points.

How far can a 2×8 ceiling joist span?

Span is determined by species, grade, dimensions, spacing, use, and load. A rule of thumb is 1.5 times a joist’s depth but in feet when spaced at 16” centers. In general, a 2×8 will span 1.5 x 8, so 12-feet. Based on all factors though, a 2×8 joist span is 7′-1” to 16′-6”, and a rafter 6′-7” and 23′-9”.

What is the maximum span for a 2×8 ceiling joist?

Depending on various factors, the maximum span for a 2×8 floor joist is 16′ 6”. The maximum span for roof rafters is 23′ 9”. For headers, the maximum span is 11′ 2”.

What size are ceiling beams?

The width and depth of decorative beams should be proportional to the size of the room. The bigger the room and the higher the ceiling, the wider and deeper the beams. In rooms with 8 or 9-foot ceilings, beams that are about 5 inches wide and 3 inches or so deep are typical.

How far can a 2×10 ceiling joist span without support?

2×10 floor joists can span up to 20′. However, this is for 12” o.c. spacing for live loads that are 30 psf. This is unrealistic because any living space or deck requires a joist that can support a 40 psf live load.

What size joist do I need?

Spacing (distance apart) of joists – centres

Size of joist mm 400mm 600mm
50 x 195 4.13 3.5
50 x 220 4.64 3.91
63 x 97 2.19 1.82
63 x 122 2.81 2.45

What size beam do I need for a 20 foot span?

Wood beam size for a 20 foot span:- as per general thumb rule, for a 20 foot span, size of wood beam or lumber joist should be 2×14 which placed at 16″ apart from centre used for residential building or projects or construction in which depth of section of beam is 350mm (14″) and width of beam is 50 mm or 2″.

What size beam do I need for a 16 foot span?

For a 16-foot spans, the wood beam has to be at least 14 inches in depth and 6″ in width (3-2×14) used for residential building, wood frame structure or projects.

What size lumber can span 24 feet?

In general terms, joist or beam which spaced 16 inches apart on Centre can span 1.5 times in feet their depth in inches. A 2×16 can span upto 24 feet.

Which way do studs run in ceiling?

This idea works better on wall studs, but if you have any outlets on your ceiling, it will be attached to a joist. If it has two plugs like many home outlets, the studs will run in the same direction as the plugs, so the next stud will be 16 or 24 inches to the right or left of it.

Are ceiling joists load-bearing?

Walls that run perpendicular (at a 90 degree angle) to the ceiling joists are load-bearing. Walls that run parallel (in the same direction) as the ceiling joints are non load-bearing. Ceiling joists are spliced over the wall.

How many joists is 12 feet?

A 12-foot long deck with joists 16 inches on center will require 10 joists.

Which is stronger 2 2×4 or 1 2×6?

The total bearing area of three 2x4s is 15 3/4 square inches, two 2x6s have a bearing area of 16 square inches. In bending, however, such as from a wind load, a 2×6 wall is considerably stronger. In tall walls, where column buckling might be a factor, a 2×6 wall would be stronger if a structural sheathing was used.

How strong is a 2×6?

According to the Codes, a 2×6 on edge with the weight pressing through 5.5” of wood will support approximately 53lbs per linear foot. So, an 8-foot length will support about 424lbs. However, a short span 2×6 on edge can support between 600 and 900lbs depending on wood species, grade, and other factors.

How much weight can be hung from a ceiling joist?

Simple – 9 lbs per square foot. If your chair does not weigh over 9 pounds—you can hang one on a joist for every foot of length. This is based on a attic floor which is designed by code to support 10 pounds per square foot and then subtracting 1 pound for ceiling weight. You should have no problem with this.

What size lumber is used for rafters?

Max. Live Load 20 lbs/ft2 (956 N/m2)

Maximum Span (ft – in)
Nominal Size (inches) Rafter Spacing, Center to Center, OC (inches) Lumber Grade
2 x 6 12 16′ – 4”
16 14′ – 11”
24 13′

What is stronger 4×6 or 2 2×6?

In general, the bending strength of a beam is directly proportional to its width and directly proportional to the square of its height. In the bottom case the 4×6 is theoretically 2² = 4 times as strong as a single 2×6, but since there are two of them it is only twice as strong as two2x6s.

Can you use 7/16 OSB on a roof?

Standard types of wood designed for roof sheathing are oriented strand board, known as OSB, and plywood, the most popular being OSB. Sheets of 7/16-inch thick, without edge support, can be used in an area where the snow load is 30 pounds per square foot.

Are 2×4 soft or hardwood?

The nicknames for lumber sizes. Softwood dimensions give thickness and width, as in 2×4 (“two-by-four”) or 1×8. Hardwood dimensions give only thickness, expressed as a fraction over 4, as in 4/4 (“four-quarter”) for 1 inch, or 12/4 for 3 inches.

Is lumber a framing pine?

Definitions of Framing Lumber Species

​Density​ is the strength of the wood and the weight. Denser wood has better structural strength, although it could be softwood, such as pine, spruce or Douglas Fir. … Texture is often used for a wood that will show on the exterior of a building and affect its final aesthetic finish.

Can I use treated lumber for rafters?

Can you use pressure-treated wood for roof rafters? – Quora. Yes you can but you don’t need to and it would significantly increase your overall price!

Can I use 4×2 for floor joists?

4×2 timber floor joists on the ground floor have been used for decades but should be no more than 16 inch or 400 mm centres and be supported at no more than 2 metre centres , 6ft or 1.8 m is preferable and practical .

How do you keep a 2×4 from sagging?

Put in back rails about eight inches from the top and bottom of the fence to stop it from warping. If your fence will be higher than 8 feet then you may want to put another rail in the middle. Once you finish building, apply a sealant to the wood. It will slow the drying process so that everything happens more evenly.

Can 2×4 be used as deck joist?

The short answer is yes. 2x4s can work for deck joists. However, they aren’t ideal for spanning long distances without bending or breaking, so you have some limitations. Choosing 2x4s for a low-sitting deck is perfect for keeping your feet out of the mud.

How do you frame a 2×4 ceiling?

How to install a stud ceiling – YouTube

How far apart should ceiling joists be for drywall?

Regular 1/2-inch drywall ceilings can be hung perpendicular if joists are spaced 24 inches or less apart (*always refer to local codes). If hung parallel, the maximum spacing is 16 inches on center.

Will 2×2 hold drywall?

Measure the length of the wall and cut a 2×2 board to this measurement. Use drywall screws to attach the 2×2 to the ceiling, using the chalk line and joist locations as a guide. … Do not screw the 2×2 into unsupported drywall — always screw into the ceiling joist. The 2×2 attached to the ceiling is called a top plate.

Can metal studs be used for ceiling?

Steel studs are beneficial for building ceilings because they are straight, light and can be purchased in longer lengths than wood studs. For low clearance areas, they also come in 1 5/8 inch widths. In many applications, installing a steel stud ceiling take less time and effort than it would with wood studs.

How do you attach a 2×4 to a rafter?

Attaching Rafters and Trusses to Header Beams – Overview of a …

Do screws weaken joists?

Meaning you could easily put screws a good 40-50% of the dimensional thickness of the lumber with no repercussions. You could put in those hooks every foot on every rafter and they would have no impact at all.