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.
normally, floor joists are spaced 16 inches apart on center. this means from the center of one upright joist to the center of the next. given that 2x8s are actually 1-¾ inches wide, it works out to be 14-¼ inches between each joist. with some structures, floor joists are required to be 12 or 24 inches apart on center.
the deck on our caravan yes has joists at 600mm it is 11metres long, i'm not made of wood and 3/4 inch thick boards from memory. it's three years old and there's no real give in it so far
the board will be going across the width of the 4.7 so 2 boards will complete a length with hardly any wastage. and i want to step the decking so it looks nicer than having one join in the middle. now i have read that centers of the joist should be 40cm apart,
install the floor or deck joists directly to the beams and ledger board with hangers rather than sitting them on top of the beams. this eliminates the width of the beams anywhere from 6-12 inches.
in general, posts should be spaced no more than 8 feet apart. some builders position them every 4 feet for a completely rigid frame. the maximum distance between footings is determined by the size of your joist material. here is a list of some common joist sizes and maximum spans. a span is the unsupported distance between two posts.
the amount of weight a 2×8 can support is going to depend on the span of the joist, and how far apart it is from the next joist. since you can span 13 with a 2×8 spf joist on 16 inch centers, but you ultimately decide to only span 8 feet with your joist on 12 inch centers, the weight bearing increases.
the screws are then driven into the ledger or end joist, depending on what type of deck you are constructing. the screws should be rustproof and here we are using screws that are 4 inches long. check the levels of the joists as you go along, using a large spirit level.
if a joist spans between two beams or a beam and a ledger, each beam or ledger supports half of the joist. the length of joist span actually supported by a beam is what determines the force that bears upon that beam and therefore the distance that a given size of beam can span before another post is required to support that beam.
the table has two column sections one for joists without a cantilever and one for joists with a cantilever. span entries are listed for 2×6 through 2×12 joists and 12 in., 16 in., and 24 in. on-center spacing. the illustrations one for cantilever joists and one for flush rim-beam hung joists
common spacing how far apart each joist is from the next for decks are 16 inches, 24 inches or 32 inches on center. the span of the joist how long a joist is between supports is determined by the same factors.
when replacing the existing boards with composite decking on a deck with 24-inch frame spacing, you will only need to add joists 12 inches on center between existing joists. for decks with 16-inch spacing, measure and mark each joist that is at 48 inches.
im building a deck, what spans can i place my beams? i plan to use 2x12's for the beams and 2x10's for the joists, how far apart do i need to place the beams, i plan to put the joists on 16' centers, the deck will be free standing. update: the deck is 18' x 31', and it will sit 36' off the ground.
now that you know your joist centres are at 600 and the span is at 1500, use the pocket span book to work out what size the joists need to be. i also reckon in this configuration you will get away with the bearers being the same timber size as the joist because the bearers only have a half load due to the 1500 width.