After some shallow drainage advice

[perky416]

Hi guys.

Some genius at some point decided to build my garage below ground level, and there is no drainage so all the rain water runs into the garage.
I have a drain hopper about 5m away from the garage door. The top of the hopper is only 6cm below the level of the garage floor.

I was thinking about installing a shallow channel drain in front of the garage door and using 40mm solvent weld waste pipe installed just under the block paving to drain the water away and into the top of the hopper (id be running it under the block paving right next to the garden wall so very little weight will ever be applied to the pipe).
I know its a bodge but aside from ripping up the block paving and installing proper drainageits all i can think of.

What do people think of this? Will it work? Or is there a better way to acheive drainage?

Thanks

 

[Hugh Jaleak]

That's not a lot of scope for a decent depth of channel, and to get a fall on the 40mm to the gulley, if you've only 60mm to play with. Personally, I'd look at a small submersible pump, run channel drain into a sump, fit the pump in the sump and run the delivery pipe to the gulley. Will allow a reasonable size channel to be fitted and more drainage capacity. Pump on a float switch so will kick in when water level rises.

 

[^woody^]

Such narrow waste pipe may well block very quickly.

What can't you install proper drainage pipe, put a reasonable fall on it, and change the hopper for a tee connector and trap or suchlike?

 

[Ian H]

The pipe down from the hopper/gully could a 300mm or more deep so you might be able to do it in 4”.

Having said that, I worked on a new build last week and the ACO’s there had a 40mm outlet (over a short distance) and they seemed to work ok.