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Low-level Merbau deck on a small concrete porch

Making a Splash

Low-level Merbau deck on a small concrete porch

Hi Everyone,


With the confidence and knowledge that I have gained from building my first deck a couple of years ago, I've started building a second deck on my front porch which is currently concreted. 


I had a great amount of help from this forum when I did my first one, as people poured in their helpful suggestions and recommendations. I've gained significant knowledge from here, as I have never seen anyone building a deck before, or had much DIY experience other than building a garden bed. 


I've started building this deck a couple of weeks ago. however it took me weeks and multiple trips to Bunnings to get the materials, especially framing timber. From what I understand, with lockdown easing there has been a significant shortage in structural timber. 


Due to the fall in porch from 11.5 - 15 cm, I had to use framing timber / L brackets of varying sizes. 


I am hoping to have a picture frame, however still trying to figure out the best way to go about it due to the unusual shape of the deck.  Wondering if someone have any ideas / recommendations that I can draw inspiration from? 


I've purchased 1.8 meter decking boards however the deck is 3.5 meter long. I've to lay two boards to reach the total length of the deck and wondering what people do when they are in this situation. 


I'm installing joists roughly 45 cm apart however right in the middle of the deck where these 1.8 meter decking boards join, there are no joists. Do you need to have a joist here just so both boards can meet in the middle of the joist? Or two joists for the edge of each these boards, so dust doesn't accumulate here?



 Also, the last joist towards outside where I need to attach a facia board would have nut and end of bolt (around 15 mm) sticking out. How do you attach facia boards on to this? screw through 15 mm Plastic space from facia board to joist??

Bunnings Team Member
Bunnings Team Member

Re: Low-level Merbau deck on a small concrete porch

Hello @Neo19


Thank you so much for sharing your next low-level deck project. Would it be possible for you to finish the framing plan so we can see where you intend to put the picture framing support? This will also tell us in which direction you will be laying your joists. Have you thought about splitting the frame into two? In this manner, you won't have to join the 1.8-meter long pieces together. You can just join two frames together which will give you a much stronger structure. As for the fascia, I suggest countersinking the nut so that you won't have to put spacers when installing the front panel. You also have the option of using the Carinya Make-a-bracket. This will allow you to make customized brackets to suit your needs. If I come across any other ideas, I'll post them here.


Let me tag our experienced members @tom_builds, @jaga, and @MGusto for their recommendations.


If you need more advice or information, please let us know.




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Making a Splash

Re: Low-level Merbau deck on a small concrete porch

Thank you for your very helpful suggestions @EricL. Countersinking certainly solves the problem. Finally some work for those larger spade bits sitting around doing nothing in my toolbox !! :smile:


When you said splitting frame into two, did you mean running a board vertically in the middle? 


Please find a drawing indicating orientation of joists. Apologies for the crude quality, I didn't really draw a proper decking plan.



Having an Impact

Re: Low-level Merbau deck on a small concrete porch


If I understand you correctly, you will need an extra joist to support the ends of the 2 decking boards. For a 45mm width joist there is plenty of room to butt both ends on the single joist. I have made a diagram to show. The only "problem" with this is that you get a single line of joins all the way across the width of the deck and some may find this not pleasing to the eye. If you had purchased longer lengths you could alternate the joins eg 2.4 + 1.1, then lay 1.1 + 2.4 so the joins are at the opposite end of the deck.

You may have already considered this, I have suggested two starting points for laying the decking boards so that there is no cutting required where the deck narrows.


Bunnings Team Member
Bunnings Team Member

Re: Low-level Merbau deck on a small concrete porch

It's great to see @MGusto has jumped into the conversation with some helpful advice @Neo19.


You might have just missed it, but I believe you'll need the double joist and spacer in a couple of other locations for your picture frame. See the image below. I'd imagine you've just left them off, and are well aware of needing them.


Depending on your opinion of breaker boards, you could run one in the middle of the deck perpendicular to your decking boards. That way, you don't have a line of boards butting their ends up against each other. You could make it into a bit of a feature.





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Making a Splash

Re: Low-level Merbau deck on a small concrete porch

Thanks for the tag @EricL 


@Neo19 your plan looks great, and as everyone else has said you will need at least one joist wherever any decking board will join another (of course you can use double-joists if you want to).


I like @MitchellMc's suggestion of a breaker board, especially as you are already planning on picture framing the deck. To be able to do this you will need a double joist with spacers (noggins) in the midpoint of the deck to be able to fix the breaker board parallel to the joists.


Best of luck with your decking adventure! 


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