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Merbau decking over concrete slab

Neo19
Making a Splash

Merbau decking over concrete slab

IMG_20191207_141119.jpg

 

Hi Everyone 

 

I have been going through these discussion boards for a while and finally mustered to courage to post a question here :smile:

 

This would be my first deck. Have done some landscaping for myself in the past including a raised garden bed, however nothing major. As far as tools, I've a drill kit including hammer drill, a cordked circular saw and a random orbital sander. 

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My proposed deck would be 350 x 370 with height from the slab between 17 - 18 cm so it stays flush with the brick and same level as my internal floor. 

 

I've been advised that i could use H3 structural timber (140 x 45) as joists and lay decking boards on top that. 

 

My questions, 

 

1. How do I attach joists to the concrete? Use galvanized angle brackets like this?

 

2. How can I adjust the height so the finished decking board stays flush? If i used 140 board + .5 bracket + 19 mm board = it would be around 165 cm height. Which is around 1.5 cm lower than bricks. Can I use plastic wedges / window packers to compensate for around 1.5 to 2 cm? 

 

3. This deck would be under alfresco cover and under eaves. In terms for water drainage, what would be helpful. Would the packers / wedges mentioned in Q. 2 help with the same?   

 

IMG_20190916_143835.jpgAlfrescoAlfrescoRough plan showing pillarRough plan showing pillar

On the last image, pillar is on the corner of the alfresco slab and the decking to the south of it would be on top of soil (this would 370 x 45 cm). Not much height difference from alfresco slab. What do I need to provide here under joist for support? Not enough height for a stirrup. 

 

Thank you very much for reading through. 

Community manager's note: Check out How to build a low-level deck for expert advice.

Re: Merbau Decking over concrete slab

Thanks @asb924 

 

which screws did you use for these joists and blocks?

Re: Merbau Decking over concrete slab

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