# A couple of deck questions.



## hugh71158 (Jan 12, 2011)

So, as I contemplate the deck I have to build to replace the now removed rotten one, some question are bubbling up - maybe someone can help?

My first thought is size. Should I keep my deck to say a 12 foot projection and use 12 foot boards, or does going out to 14 feet complicate the issue?

And what about thickness? Boards that are 2 inches I think look (and are) sturdier, but will 1 inch boards do just as good a job with closer joists? The maximum height from the ground will be three feet.

I appreciate and help I can get. 

Hugh


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## richgreer (Dec 25, 2009)

Based on the information you have shared it is hard to say if going to 14' will complicate the issue.

Most regular pressure treated decking material is 5/4"

I think a more important question is what material to use. Pressure treated lumber is the most common and the cheapest. It has a relatively limited life expectancy (10 - 15 years). Artificial materials cost more and last longer.

My deck is made of ipé which is a very hard wood that will last forever with or without treatment. When I built the deck about 10 years ago, it costs about twice as much as pressure treated lumber but if you plan to have the deck for the long term (I do) it's worth it. I'm 60 years old and I know this deck will outlast me - and it looks good too.


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## hugh71158 (Jan 12, 2011)

Thanks for the reply. I think we will be out of here in 5 - 7 years, so maybe ipé is too much of an investment. Maybe you could answer this - the local planning department are saying that the maximum overhang for decking id Lj/4 - what exactly does that mean? Maybe I am just used to different terminology. (from Scotland)

Hugh


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## crank49 (Apr 7, 2010)

Hugh, I am not sure what the Lj/4 means for sure, but being an engineer, I know the strength of material in cantilever arrangement is divided by 4.

In other words, a beam that spans 8 feet between two supports will only support 1/4 as much load, or 1/4 the distance if cantilevered ( over hung). So that same 8 ft beam could support the same load if over hung 2 ft past the end support.

That makes me conclude the Lj/4 might mean the over hangs are allowed to be 1/4 the span.


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## CampD (Nov 8, 2008)

LJ/4 = Length of Joist dived by 4 = is the maximum over hang. This is the new standard.
(used to be 1/3). The codes for decks have changed drasticly the last couple of years.
Also has to do with joist size x length. (personally I wouldn't overhang more then 3')
Ideally if you plan on building a bigger deck I would also change the footings to the newer codes, that way 
they'd be assured to carry the load.


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## hugh71158 (Jan 12, 2011)

Guys, thank you VERY much, this clarifies everything. Thank you!

Hugh


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## Grandpa (Jan 28, 2011)

You also need to consider the length of the materials. In my town 5/4 deck flooring only comes in 16 ft. lengths. the 2×6 or 2×8 material can be bought in 12, 14, 16 ft lengths so think about the waste also.


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