Sharp sand & Cement porcelain patio base

[Oxdale]

Hi

 

My patio has been laid on a sharp sand and cement base (mot 1 underneath)

 

I understand that this type of base is designed to be porous.
 

My question is that is a concrete base like this still porous when it freezes? My concern is that should there been any gaps under the patio, will any water drain when it freezes?

 

thanks

 

 

[nod]

You don’t want water draining through 

They will lift with frost 

Better to fall towards a drain or border