250 mm x 400mm
Depends on how much weight is above it!! but on 1 -2 story wood framed structures triple 2x12's glued and nailed will do the trick
10
This is the size of a typical single family house in the US. Imagine a rectangle the size of 20 feet by 70 feet, or two rectangles the size of 20 feet by 35 feet, or eight rectangle s the size of 10 feet by 17.5 feet, or ... well you do the math. A room 20 feet by 35 feet is typical for a medium size living room. A room 10 feet by 17.5 feet is typical for a medium size bedroom. If you can imagine these small sizes then it's just a matter of imagining several of these to arrive at 1400 square feet.
Don't know what you mean by actual size. It could be 80 x 10, but could be any shape.
It depends on what the beam is made of.
250 mm x 400mm
W8 x 24
about 80 feet (24 metres) long with a maximum beam length of around 10 feet (3 meters)
Around 10 feet long
5-10 feet
wing span 10 feet originaly 30 feet
Depends on how much weight is above it!! but on 1 -2 story wood framed structures triple 2x12's glued and nailed will do the trick
10
10
My guess is size 10
UK size 10