the space between the ends of boards should always be 1/8 inch. typically the end cuts will not swell as mush as the sides, which run with the grain.
how to properly space deck boards decking is structural in addition to being an aesthetic element. decking must be able to support 40 lbs live load 15 lbs dead load as it is supported between joists.
then again, if you space wet boards 3/16 inch right from the start, gaps will open up way more than ¼ inch and look terrible. the best approach is to begin with some sense of the moisture content
cedar deck board spacing should be 1/8. this measurement is usually referred to in two ways: this measurement is usually referred to in two ways: sixteen penny nail
decking spacing. discussion in 'in the garden' started by lmanning, 3 jul 2008. my friend has just put some decking down and left a 7mm gap between the boards. he is now worried that with shrinkage these will become excessive.
a 1/8-inch gap is a reasonable end-target, but since wood decking often shrinks after it has been installed, this shrinkage must be taken into account during installation. the photo above left shows an older wood deck that has good drainage; the gaps between these boards averaged about 3/16'.
that's extreme and i've sen it only twice - but it is common to see twisted and lifted and cupped decking because too little space has been allowed between boards. much less a concern in covered areas than on exposed decks. often decks are laid in summer and then the problem arises with autumn/ winter rains.
this video is about the importance of spacing treated lumber decking when installing it. i also touch on the importance of putting the crown down to help prevent cupping in your boards.
tools and tips for proper deck board spacing. give it dry time if you have the time and a place to keep the wood out of the elements, give it two or three weeks to dry out before installing. the sweet spot most people agree that 3/16 is a good gap between boards. going more than a ¼ may get a little too wide.
composites composite deck boards will have basically no shrinkage so they need to be spaced with gaps from the get go. make space in moist areas if you live where there is a fair amount of moisture in the air the boards will swell. account for this in the spacing by giving it a little more room between boards.
when deck boards are too tight, water will not be able to drain, causing the wood to rot over time. the most common spacing measurement between deck boards is 1/8 inch. a convenient way to get consistent spacing is by using a 6-penny or 8-penny nail between each course of decking; the width of the nail is 1/8 inch.