What size header do i need for a garage door: (8′, 9′, 10′, 12′, 14′, 16′ & 18 foot)

What size header do i need for a garage door:
(8′, 9′, 10′, 12′, 14′, 16′ & 18 foot) | 8 foot garage door header size | 10 foot garage door header size | 12 foot garage door header size | 14 foot garage door header size | 16 foot garage door header size | 18 foot garage door header size | 20 foot garage door header size.

If you want to make garage door for your single, double or 3 car parking, there is a lots of questions comes in mind what is correct header size width and their thickness for garage door and how to install garage framing and what size header is required for garage door. There are few points you should know before framing.

What size header do i need for a garage door: (8', 9', 10', 12', 14', 16' & 18 foot)
What size header do i need for a garage door: (8′, 9′, 10′, 12′, 14′, 16′ & 18 foot)

Garage door Rough openings as the size of the opening before the finished lumber has been added to the jambs. Before you add your framing, the rough opening should be larger than the garage door you’ve chosen. Garage door rough opening should be 3 inches wider than the door width measured from the left and right edges. So, in a 9-foot wide garage door, the rough opening width will be 9 foot 3 inches wide.

The distance between the garage floor and the rough header should be placed one and a half inches (1-1/2″) taller than your new garage door’s height. For example, in a standard Seven-foot-tall garage door, the header should be placed at height of 8′-1-1/2″ feet above the finished floor.

The header itself should be nine inches longer than the door. The standard garage door width and height can vary by where you live, but is usually it is 8 feet wide by 7 feet tall, or 9 feet wide by 7 feet tall for a single car garage door and 16 feet by 7 feet for a double garage door.

Concluded: 1) Garage door rough opening should be 3 inches wider than the door width, 2) header height is one and a half inches (1-1/2″) taller than your new garage door’s height and 3) header itself should be nine inches longer than the door width.

A header is a horizontal beam that transfer the load to foundation that coming from roof and wall, generally made of timber or Laminated veneer lumber or LVL or Glulam (Glued laminated timber) that provided along the opening of garage in full length for garage door, doorway, window, skylight or stairway. Glulam and LVL header provide structural support in wood frame construction.

Typically header is provided at least twice size of 3- 1/2 inches then any other surrounding members such as rafter purlin and stud. It is often made of two joists, rafter or studs. It runs between full length supports and along its length and carry the load of shorter studs, joists or rafter that terminate at the opening.

A common width of LVL (Laminated veneer lumber) or glulam garage door headers is 3-1/2 inches, which fits conventional 2×4 wall construction. For 2×6 wall construction, a 5-1/2-inch-wide LVL or glulam beam provides the perfect fit.

The header helps to provide support, stability and strength to the top and side sections of the garage door frame. The header for a window & door is seems like a bridge that transferring the weight above it to the floor and foundation below. Doors in a load-bearing wall that holds the weight of the house, created by beams and trusses, need a larger header than those in non-load-bearing walls.

The header is usually made out of dimensional lumber or LVL or Glulam beam installed on its edge. Calculating and know the size of the header depends on what the header needs to support.

Garage door headers carry the weight of the roof and wall structure above and transfer it to the trimmers down to the floors and foundations below. Longer openings such as in garage required larger headers. Load bearing walls those that carry the weight of joists and trusses require larger headers than nonbearing wall.

In this article you know about what size header do i need for a 8′, 9′, 10′, 12′, 14′, 16′ & 18 foot garage door that will help you in better understanding and to figure out or estimate of LVL header or Glulam header size and their depth and help in important for you to use the right size header.

What size header do i need for a 8′, 9′, 10′, 12′, 14′, 16′ & 18 foot garage door

LVL or Glulam beams have ability to span long distance due to their dimensional stability and cost competitive value, makes and ideal option for garage door headers particulars, particularly for large car and three car opening.

A common width of Glulam garage door header is 3- 1/2″ inches which fits conventional 2×4 wall construction. For 2×6 wall construction, a 5- 1/2 inches wide glulam beam provides the perfect fit.

You will need a minimum 3 1/2″ X 11 7/8″ net header size for a garage door opening from a 8 foot to a maximum 18 foot that perfectly fits to 2×4 wall construction. That would take care of the roof load, wind and seismic shear loads.

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Header size for single car garage door

The standard single-car garage door is 8 to 9 feet wide and 7 to 8 feet high for most home. New construction frequently offers 9×7 garage doors opening. Increasingly, garage door widths of 10 feet are being constructed. These garage door dimensions tend to be the same for both attached and detached garages.

As per general thumb rule and guidelines, for a single car garage door, you will need 2- 2×8 or 4×8 size of header made of dimensional lumber. If you have choice of selecting Laminated veneer lumber or LVL or Glulam (Glued laminated timber) for a single car garage door header, you will need 3.5″ × 9 1/4″ size of header which are 3.5 inches wide and 9 1/4″ deep which are perfect fits to 2 × 4 wall construction. For 2 × 6 wall construction, you will need 5 1/2″ × 9 1/4″ size of header for a single car garage door.

Header size for double car garage door

Many homeowners have two cars and need garage space to shelter them both. The standard size for double garage doors is 16 feet wide and 7 to 8 feet high.

As per general thumb rule and guidelines, for a double car garage door, you will need 5 1/2″× 11 7/8″ or triple 1 3/4″ × 11 7/8″ size of LVL (Laminated veneer lumber) or Glulam (Glued laminated timber) header which are perfect fits to 2×6 wall construction. For 2×4 wall construction, you will need 3 1/2″ × 11 7/8″ size of header for a double car garage door.

Important Link

 Rough opening for a 32″, 28″, 30″, 24″, 34″ & 36 inch door

What size header do i need for a 8 foot garage door

As per general thumb rule and guidelines, for a 8 foot garage door opening and 2×4 wall construction, you will need 2- 2×8 or 4×8 size of header made of dimensional lumber. If you instal LVL (Laminated veneer lumber) or Glulam (Glued laminated timber), you will need something like 2- 1 3/4″× 9 1/4″ size of LVL or glulam header for a 8 foot garage door.

What size header do i need for a 9 foot garage door

As per general thumb rule and guidelines, for a 9 foot garage door opening and 2×4 wall construction, you will need 2- 2×10 or 4×10 size of header made of dimensional lumber. If you instal LVL (Laminated veneer lumber) or Glulam (Glued laminated timber), you will need something like 2- 1 3/4″× 9 1/4″ size of LVL or glulam header for a 9 foot garage door.

What size header do i need for a 10 foot garage door

As per general thumb rule and guidelines, for a 10 foot garage door opening and 2×4 wall construction, you will need 2- 2×10 or 4×10 size of header made of dimensional lumber. If you instal LVL (Laminated veneer lumber) or Glulam (Glued laminated timber), you will need something like 2- 1 3/4″× 11 1/4″ size of LVL or glulam header for a 10 foot garage door.

What size header do i need for a 12 foot garage door

As per general thumb rule and guidelines, for a 12 foot garage door opening and 2×4 wall construction, you will need 2- 2×12 or 4×12 size of header made of dimensional lumber. If you instal LVL (Laminated veneer lumber) or Glulam (Glued laminated timber), you will need something like 2- 1 3/4″× 11 7/8″ size of LVL or glulam header for a 12 foot garage door.

What size header do i need for a 14 foot garage door

As per general thumb rule and guidelines, for a 14 foot garage door, you will need something like 3 1/2″× 11 7/8″ or double 1 3/4″ × 11 7/8″ size of LVL (Laminated veneer lumber) or Glulam (Glued laminated timber) header which are perfect fits to 2×4 wall construction.

What size header do i need for a 16 foot garage door

As per general thumb rule and guidelines, for a 16 foot garage door, you will need something like 5 1/2″× 11 7/8″ or triple 1 3/4″ × 11 7/8″ size of LVL (Laminated veneer lumber) or Glulam (Glued laminated timber) header which are perfect fits to 2×6 wall construction. For 2×4 wall construction, you will need 3 1/2″ × 11 7/8″ size of header for a 16 foot garage door.

What size header do i need for a 18 foot garage door

As per general thumb rule and guidelines, for a 18 foot garage door, you will need something like 5 1/2″× 14″ or triple 1 3/4″ × 14″ size of LVL (Laminated veneer lumber) or Glulam (Glued laminated timber) header which are perfect fits to 2×6 wall construction. Thus, you needed 5 1/2″× 14″ size of LVL header for a 20 foot garage door.

What size header do i need for a 20 foot garage door

As per general thumb rule and guidelines, for a 20 foot garage door, you will need something like 5 1/2″× 16″ or triple 1 3/4″ × 16″ size of LVL (Laminated veneer lumber) or Glulam (Glued laminated timber) header which are perfect fits to 2×6 wall construction. Thus, you needed 5 1/2″× 16″ size of LVL header for a 20 foot garage door.

Conclusion:-

You will need a minimum 3 1/2″ X 11 7/8″ net header size for a garage door opening from a 8 foot to a maximum 18 foot that perfectly fits to 2×4 wall construction. That would take care of the roof load, wind and seismic shear loads.

For a 8 foot garage door and 2×4 wall construction, you will need 4×8 size of header made of dimensional lumber, for a 9 & 10 foot span – 2- 2×10, for a 12 foot 2-2×12 and for a 14 foot garage door you will need 3 1/2×11 7/8 size of LVL header.

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