Thank you for your question.

Postcrete is designed for use with domestic fencing and small gates, although it has been used for garden structures such as gazebos successfully on many occasions this is not what we would consider a primary function of the product.

Best practice would be to use something more conventional such as our High Strength Concrete (https://tarmac-bluecircle.co.uk/product/high-strength-concrete-trade/), if speed of set is a primary concern, a concrete mix of our Extra Rapid Cement (https://tarmac-bluecircle.co.uk/product/extra-rapid-cement-trade/) with ballast. Whichever option you decide to use approximately 25% of the post length should be below the ground.

I hope this helps and allows you to use you ‘engineering judgement’ to make the correct decision for you and your project. For more guidance feel free to view our ‘Builder’s Guide’ – https://tarmac-bluecircle.co.uk/wp-content/uploads/2018/01/Builders-Guide-170118a.pdf

Kind regards