Soakaway advice

[Jimmylondon07]

Wonder if I could trouble you for some advice about our driveway as it’s keeping me up at night. We looked for a contractor to do the work that has a registered company, a local phone number, trade-body membership and a presence on sites like checkatrade and trustatrader. Having seen some boards locally and evidence of his work we decided to go with this specific trader over some others.

 

The drive itself is fully block paved with tumbled concrete blocks and kiln-dried sand in the joints. It looks great but the major thing troubling me is the soakaway he’s put in. My driveway is about 8m x 8m and slopes towards my house reasonably steeply. He has put aco drains across the entire width of the front (also about 8m) and connected these to a soakaway which, having measured it, is only about 2.5m to 3m out from the front of my house, presumably because he’d have had to dig down really far further up the drive in order to make it deep enough to be the full 5m away with the appropriate gradient from where the aco drains are. This soakaway should be taking water not only coming down the drive but also from the front of my roof. I don’t think he used a plastic crate (filled it with rubble as far as I can tell) and I am also not sure if any water volume calculations were done to take in to account both the drive and roof water. 

 

Of course I only found out about the regulations for this on speaking to my neighbour afterwards who had just returned from his holiday (building inspector). The contractor asked me if that spot was OK for the soakaway and, not knowing what I don’t know, I said OK. However he would definitely know the regulations himself, I don’t think there’s any doubt about that.

 

I am now wondering what to do about it. He has been paid in full and as I say the actual finish is very good, but this is really nagging at me. I don’t want to fall out with him but having spent a lot on the house I really don’t want to face damp or even subsidence issues. He claims to offer a 5 year guarantee on his work.

 

Am I worrying unnecessarily or what would you suggest I do?

[ToughButterCup]

5 hours ago, Jimmylondon07 said:

.. .

It looks great but the major thing troubling me is the soakaway he’s put in

....

This soakaway should be taking water not only coming down the drive but also from the front of my roof.

...

Am I worrying unnecessarily... ?

 

Probably. 

Does the work done cope with the water delivered to that area of your house ? 

 

If so, bingo! Tea, medals. Peaceful sleep. 

 

If not, (... should be...) then come back here and describe the problem in some detail. 

 

Relax we'll all pitch in to help. We love a challenge. 

 

 

[tonyshouse]

Try it and see if it ever fills up and overflows.probably be ok but it is poor 

[Jimmylondon07]

Thanks to you both. I have decided to monitor it over a few days of rain as they only completed it last week and it’s been dry since. I guess the indication that it’s not adequate is that the aco drains will just backfill and overflow?

[tonyshouse]

Yes , ok in deluge but should normally not 

[Jimmylondon07]

I got a reply from the contractor as follows:

 

'the soakaway is your normal old fashioned soak away , huge hole filled with hardcore , bricks , concrete aggregate with pipe connecting into it via your aco drainage system about 4 metres away from front house'

 

I know the crate method is desirable/best practice, but is there anything to say it HAS to be done that way? Just trying to establish where I stand.

 

Thanks

 

Jimmy 

 

[PeterW]

53 minutes ago, Jimmylondon07 said:

 

I know the crate method is desirable/best practice, but is there anything to say it HAS to be done that way? Just trying to establish where I stand.

It’s best practice but wasn’t specified, and gravel or hardcore soakaways work fine. If the spec said “crate soakaway wrapped in geotechnical to size xx/CuM with infiltration of yy, minimum invert depth zzz mm” then you would have an argument. 
 

As it is, there is a soakaway. Tbh if it’s below a block pave driveway then I would prefer traditional over crates unless it’s been designed properly. 
 

I don’t get either why it takes the front of the house and the drains ..? Surely the front of the house has an existing soakaway / drainage ..?