patio 6" below damp course why?

[ss_fraser]

The 150mm dist from DPC to external ground level is an industry standard value used throughout the UK.

The reason for sloping away from the DPC is to ensure that you do not end up with a large puddle against the external leaf of your house.

Please note with any drainage system if it is not properly installed or with the passage of time and debrie and a a lack of maintenance could block resulting in puddling at the bottom of your external wall.

Personally, I would try and maintain a small slope back away from the house and have drain installed in lowered section say 600mm away from the wall so if the drain blocks it gives you a chance of clearing without water standing against your external wall.

Please remember wet masonry could become damaged depending on the type of brick, resulting in the face of the brick being damaged..

 

[jray]

My goodness, you guys really do know how to make me laugh . I've nothing to contribute this time round, but thanks for the chuckles, and hope you get it sorted out carpetkarl!

 

[k2kris]

You could always slope the patio to a central drain rather than sloping to the house. Surely this would solve all your problems?

I would stand by the minimum 150mm below DPC.....

 

[ianp808]

if you know what a french drain is
why ask the question