My house has a front extension (built many years ago) that sticks out further than my neighbour's (attached) front wall. It has a slate DPC but my neighbour's concrete drive abutts my extension and is about 8 inches above the DPC. He has said that he doesn't mind me cutting some of the concrete away so there is a trench between his drive and my wall.
What can I do with the trench to ensure that my wall stays clear and dry? A surveyor mentioned a "French Drain" is required and said something about pebbles but I've so far been unable to find a definitive solution to this problem. Can anybody help?
Un-bridging of DPC
-
84-1093879891
Hi Vince,
this is becoming something of an FAQ - I might have to create a page showing the various ways of resolving this particular problem. However, here's a sketch showing how your partiular situation could be dealt with...
...does that help? Just ask if you need further explanation. :)
Notes:
<ul>
<li>The perforated land drain will need to be connected to the SW system or a soakaway at some point.
<li>The Terram 1000 membrane helps prevent the gravel becoming silted-up with crud and whathaveyou over time.
<li>The impermeable membrane could be a drainage composite, or you could use bitumen 'tanking' or similar. It could actually be omitted unless there is an exceptional water flow regime and you have regular inundation of this wall.
<li>The flag-on-edge ensures the sub-base or sub-grade beneath the existing concrete doesn't fall into the drainage channel. I've shown a 450x50mm pcc flag, but you could use almost anything to suit you taste/pocket. :)
<li>By cutting back into the existing concrete, you give yourself more working space and it can be patched in with fresh concrete or grano once the flag-on-edge is in position.
<li> The gravel on top of the permeable membrane could be a decorative type, rather than the larger 20-50mm clean gravel used within the channel as backfill.
</ul>
this is becoming something of an FAQ - I might have to create a page showing the various ways of resolving this particular problem. However, here's a sketch showing how your partiular situation could be dealt with...
...does that help? Just ask if you need further explanation. :)
Notes:
<ul>
<li>The perforated land drain will need to be connected to the SW system or a soakaway at some point.
<li>The Terram 1000 membrane helps prevent the gravel becoming silted-up with crud and whathaveyou over time.
<li>The impermeable membrane could be a drainage composite, or you could use bitumen 'tanking' or similar. It could actually be omitted unless there is an exceptional water flow regime and you have regular inundation of this wall.
<li>The flag-on-edge ensures the sub-base or sub-grade beneath the existing concrete doesn't fall into the drainage channel. I've shown a 450x50mm pcc flag, but you could use almost anything to suit you taste/pocket. :)
<li>By cutting back into the existing concrete, you give yourself more working space and it can be patched in with fresh concrete or grano once the flag-on-edge is in position.
<li> The gravel on top of the permeable membrane could be a decorative type, rather than the larger 20-50mm clean gravel used within the channel as backfill.
</ul>