The odds are pretty good that even if you’ve never built a deck before you just know – intuitively somehow – that the deck boards are supposed to run a little bit longer than the perimeter framing. Why, though?
You want to let your deck boards overhang at least a couple of inches for a couple of reasons. For starters, it offers a cleaner and more polished aesthetic. On top of that, the overhang helps your deck last a little longer. Finally, stair nosing, and deck board overhang actually gives a bit of extra protection to the underlying framing itself.
Sounds like plenty of reasons to let the overhang go, right?
But how far should you let that overhang run?
Let’s find out right now!
How Far Should Deck Boards Overhang?
The actual amount of overhang you leave on your boards when putting down decking is going to be determined largely by the kind of material that you’re using, the space you have available, and how you want your deck to look when it is finished.
A lot of professional deck builders recommend that you leave at least ½ inch of overhang on all of your deck boards regardless of the kind of material that you’re working with.
Other deck experts say that you can get away with a slightly smaller overhang (maybe ¼ of an inch), and other deck builders recommend going just a little bit bigger – three quarters of an inch of an overhang seems to be the sweet spot that way.
Any longer and you could be getting into a little bit of trouble (not to mention things might look a little weird).
With composite materials, though, the overhang isn’t quite as important as it is when you are building with wood.
Pressure-treated, cedar material, and other wooden materials need to be extended beyond the framing for a couple of reasons, not the least of which is to make sure that water doesn’t find itself drowning the underlying framing and substructure of the deck itself.
With composite materials, though, that kind of water protection approach is a little unnecessary.
Water isn’t going to beat up on composite decking materials the way it does with wooden ones.
All the same, that quarter inch to half-inch overhang serves a number of functional purposes regardless of the kind of material you have selected and it just flat-out looks cleaner.
Stick to that and you’ll be good to go!
Why Overhang at All?
Protect Framing
The number one reason to overhang your deck boards on your deck is to protect the underlying framing below.
If your framing is exposed to a lot of moisture, a lot of UV damage, or even just a lot of wind and weather it is likely going to become compromised a whole lot faster than if it had a “shall” with deck boards running overtop it.
It doesn’t take a whole lot extra to run these boards long (a full inch in total if you go with ½ inch overlap) but it offers a ton of protection at the same time.
Nicer Look
On top of that, the finished result is a whole lot cleaner and the look is just a lot nicer than if everything was flushed up.
Time Saver
Of course, the fact that you can run your materials long (way beyond the actual overhang you are going to end up with) while you are building everything and then snap a line and cut all of your boards that wants to get a uniform look is a serious timesaver.
Instead of having to cut every single piece to carefully fit your deck as if it was a puzzle you’ll instead be able to lay things down rough and then trim up the edges when you’re done. That’s going to be a much more efficient way to put your deck together.
Safety For People
A slight overhang on the front of your deck (where your steps are) should be designed to mimic the nosing of each individual stair.
This allows for an effortless transition as you go from step to step to the top of the deck. You won’t feel uncomfortable, and you won’t be tripping people up at the top. They won’t have to worry about navigating a flushed up top step or a gigantic overhang they weren’t used to with the stairs.
When all is said and done, the overhang is going to help with:
- Protecting individual joints in the framing of your deck
- Moving moisture away from the deck more effectively
- Keeping all your deck would in better shape
- Does a great job of blending in with the nosing on your stairs
- Finishing the deck a whole lot easier by snapping aligning cutting your overhang at once
… And so much more!
Should Composite Overhang, too?
If you are wondering if you should let your composite decking material overhang as well, even though this doesn’t offer the same benefits overhanging wood construction materials would, we can help you out:
Yes! Go for the overhang!
Even if the utilitarian benefits of overhanging wooden construction materials on a deck are eliminated are little bit by going with composite you still get the aesthetic look that people expect with a deck.
The overhang is the way to go for sure!
Closing Thoughts
When trying to figure out how far your deck boards should over run your deck framing think about a couple of things:
- How much material do you have to work with?
- Do you need a functional lip or are you just doing this for aesthetics?
- Are you mimicking the overhang near your stairs to match the nosing?
If you cover all of those basics – and leave at least ½ inch overhang on the perimeter of your deck – you aren’t going to have much to worry about.
This goes for both wooden and composite materials, too.
Wood certainly uses the overhang a little more functionally than composite materials will, but the overhang adds a lot from an aesthetic standpoint that you would have lost if you tried to flush everything up.