Decks/joist question



Thanks in advance for your help!!

I have decided to tackle a "deck" project myself - time will tell if that is the right decision or not...

The deck of the front screened-in covered porch of my 1937 Florida bungalow has rotted, especially around the edges.  Someone had installed untreated plywood on top of the original decking, hardie board on top of that, and tile on top of that.  No wonder, right?

I considered using composite material, but have settled on ipe wood, which I understand has special installation requirements.  Any advice regarding that will be greatly appreciated, but not the main thrust of my question.

When I tore up the old floor, I found that the existing joists (running parallel to the house) are 24" on center.  The maximum recommended span for ipe is 16".  I've started installing extra joists in between the old ones at 12" (halfway between).  I got to thinking that, since I'm face screwing the boards, putting screws on every board every twelve inches might be a bit of over-kill.  I'm also concerned about the finished look with that many holes (decided not to plug them - got brown-colored headcote screws instead).  

Do you have any recommendations?  I thought that perhaps I could remove the extra joists I've installed and put them at 16" from the ledger board, regardless of where the old ones fall. But I like the idea of having support every 12".  The porch gets alot of use.

If you couldn't tell, this is all very new to me!  Any questions will gratefully be answered.




I understand your concerns about having so many screws. You can still go with the 12" OC joists but set only one screw every two feet, alternating edges of the deck board. Since ipe wood is so dense, you must pre-drill for screws so that they don't snap off.

Good luck on your project. It should turn out beautiful.



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Daniel Humphrey


I can answer all questions concerning design and construction of outdoor wooden decks and stairways, particularly those suitable for timberframe homes, and especially for colder climates where snow is a factor.


I've been a timber framer for 20 years, working as a general contractor who designs and builds custom timberframe homes, working as much as possible with local materials, from foundation to finish. I've made massive decks for commercial lodges and small decks for houses in town. These decks have varied in style from round timber to Victorian ginger bread. I also have studied and tried out enough deck styles that I know which kinds are the most cost effective and easiest to make to meet code requirements. I also have expertise in designing, building, and setting up pre-fab remote camp facilities on terra firma or temperate glaciers for research and expeditions, using helicopters for support.

B.A., M.F.A.

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