Why would you want patio fall towards house? - Sorting my patio drainage

tindari2003 · Post: # 47532Post **tindari2003** Tue Mar 30, 2010 8:40 am

Hi all, this is my first post and I'm a girl so be nice. Our back garden floods pretty badly due to run off from fields behind. Our grass steps down about a foot to an old flagged patio that also falls slightly towards the house (and is only a brick below the DPC). Consequently, when we flood the house wall gets soaked until it runs down the side of the house and into the garage SWD. I've had one contractor who to my suprise propsed a new pIC patio with a fall towards the house and an interceptor butting against the wall. The 2nd contractor has propsed more what I would have expected, to have a retaining wall with weep holes for the grass, then an interceptor, then the patio sloping away from the house- kind of like the picture below: http://www.pavingexpert.com/archv406.htm

my question is why would the first guy propse the fall towards the house when it's not really necessary? why would it be better? many thanks for your replies in advance, I want to make sure I'm getting this right
???

Post: # 47533Post **seanandruby** Tue Mar 30, 2010 10:57 am

probably because the ground is falling towards your house and he does'nt want the hassle of digging out extra soil to reverse the fall.

tindari2003 · Post: # 47535Post **tindari2003** Tue Mar 30, 2010 1:02 pm

hmm thats what building control said as well (I work for the council handily). does the scheme that the other guy has proposed sound ok then? he's coming back on thursday so is there any potential pitfalls with this type of system that I should be aware of?
many thanks again

irishpaving · Post: # 47536Post **irishpaving** Tue Mar 30, 2010 2:09 pm

I think what the first installer means is that the patio will fall towards the house but will pick up run off into a channel drain running against the brick work.
There should be a bit of a difference in the price between the two installers.
Not sure why you would go with pic but i suppose it's about preference.
Second option is much better but i would ask both for a written spec

Am also curious about the interceptor.

tindari2003 · Post: # 47539Post **tindari2003** Tue Mar 30, 2010 2:49 pm

yes you assume correctly in that the drain runs along the brickwork of the house. the bit that worried me with channelling the water towards the house is how quickly the water rises and starts flooding the garden, if that drain along the house wall couldn't cope then surely I'm going to have the same problems as I've got now. Should the second contractor be dearer then? he's quoting for flags but is breaking it down so I can see how much the labour will be etc. the PIC guy was 600 quid cheaper if he relaid the existing flags, the area is about 9 m by 3

irishpaving · Post: # 47541Post **irishpaving** Tue Mar 30, 2010 4:09 pm

Only thought it would cost more if the retaining wall was been built by the second contractor.

Personally I never like to run a channel against the wall, I would always keep the channel 200-300mm away and tilt the block/concrete towards the channel away from the brickwork.

The second installer option will look better imo and as i said i personally prefer flags over pic any day but it's down to personal choice.