How to build a composite deck base frame of 200mm height?

[ankitp]

Hi all

I am building deck over concrete in alfresco. The height is 200mm. 

Can you please suggest how to build base frame structure to achieve 200mm height with composite decking boards (20mm). 

Base timber available in Bunnings are height 90mm, 140mm and 190mm. 

Do I need to add steps at the end (90 mm) as 200mm may be too high? 

 

[EricL]

Hello @ankitp 

Welcome to the Bunnings Workshop community. It's wonderful to have you join us and thanks for sharing your question about building a deck.

Your space of 200mm is ideal as it will provide excellent ventilation. You can use the 90mm and 140mm but not the 190mm as it is too big. For example, if you use the 90x45 timbre frame plus the 23mm Ekodeck panel you'll have a total of 113mm. This will leave you with a gap of 87mm which is good for air flow under your deck.

I suggest having a look at these guides - How to build a low-level deck by @Adam_W and How to build a deck by @MitchellMc. You'll be able to pick up some very good tips regarding deck planning.

I also suggest having a look at this discussion - Low-level composite deck over concrete and soil by @oninpena. It's an excellent example of building a deck with angle brackets and adjustable pedestals.

I also suggest having a look at the Bunnings deck building guide:

• How to plan out your deck
   
• How to set out a deck
   
• How to install stumps
   
• How to install bearers
   
• How to install joists
   
• How to lay decking
   
• How to add a step to your deck.

If you have any other questions, please let us know.

Eric

[ankitp]

Thanks Eric for the advise. 

I looked at topics you suggested but I want deck at same level as the door which is 200 mm. Can i use 140 mm and 40 mm pedestals to achieve 200 mm? Any issue with pedestals with 140 mm timber? 

[EricL]

Hello @ankitp 

If you are thinking of using the 140mm timber piece, please keep in mind that this will reduce the gap under your deck and slow down the airflow underneath. In regards to the pedestal, I suggest using the Builders Edge 35 - 60mm Smallfoot Pedestal Feet as it has a larger a larger footprint providing better stability.

If you have any other questions we can help with, please let us know.

Eric

[ankitp]

Thanks @EricL 

I found another post with similar situation that i have. 

https://www.workshop.bunnings.com.au/t5/Outdoor/Deck-on-concrete/td-p/44963 

Mitchel suggested to use 90 x 45mm timber with 70 - 170 mm pedestal feet. Is this something ideal? considering air flow and stability of the deck? 

Can you please also help me with how many pedestals i will need for 3.7 (W) x 4.5 (L)?  

[EricL]

Hi @ankitp 

Using the 90x45 is much better as you will have a larger gap under the deck. If you are using the 90mm timber piece we often recommend placing the pedestal feet at least 1 meter apart. 

I suggest drawing your decking frame on paper first. This will give you a better idea of the timber spread; You can then start positioning the pedestals in your drawing. Once your drawing is finished, I suggest sharing it with the community and any questions you might have.

If you need further assistance, please let us know.

Eric