Hello everyone,

I am building a Granny Game house and need advice on materials and septic tank treatment options. Should I choose a traditional reinforced concrete tank or a composite or plastic septic tank for durability, cost savings and low maintenance?

Can everyone share:

Who has used a composite or plastic tank, how does it compare to concrete in terms of durability, crack resistance, cost and maintenance?

Technical notes when constructing on weak soil, near water, waterproofing or installing drainage pipes?

If choosing concrete, should it be pre-cast or poured on site to avoid cracking and seepage?

Looking forward to receiving practical experiences from everyone. Thank you very much!