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Posted: Sat Apr 20, 2013 3:14 pm
by ricky
Hi,

The 40ft driveway and garage are located on a slope away from the road so have been told it can be laid with non permeable blocks as using permeable would risk undermining the house foundations should too much water leak though the blocks.

So a linear drain would be fitted in front of the garage with a soakaway to the side of the garage.
However whats been done is to make a hole 1ft cubed and filled with hardcore to the front of the garage so all the water from the linear drains bottom outlet will drain under the garages concrete floor and in to the hardcore infill and foundations.
The garages footings /base walls are up to 4 -5ft deep due to the slope of the land

This doesn't seem right to me partic as when it really pours the water easily floors down the drive and into the garage, which is why we wanted a really good drain putting in.
Just cannot see how the 4" hole going into an old and well compacted garage base could take it - or are we wrong ??

As mentioned in other pages of the forum the water should not be allow the soak down to the foundations of any structure; so find it hard to believe thats not going to happen to the garages foundations ??


Help please !

Posted: Thu Apr 25, 2013 12:05 am
by seanandruby
is there a reason why you can't take it to an existing manhole for storm/surface water? Not withstanding, then you need to drain to a soakaway of cratyes not hardcore. (if ground conditions and permeability allow ) 5 metres from any building. Another alternative would be to set up a pumping system. 1ft by 1ft dimensions would be worse than useless, whoever gave you that figure needs ''a bag of oats for his horse.'' quote from boss

Posted: Thu Apr 25, 2013 12:20 am
by local patios and driveway
soakaways... 5m from any building 2m from any boundary here in the south east

Posted: Thu Apr 25, 2013 6:32 am
by seanandruby
midnight typo lopad. Cheers for pointing it out, all corrected. I'm south east to :)

Posted: Wed May 08, 2013 11:39 am
by Ecogrid
New regs mean that driveways must by law demonstrate sustainable drainage. This is an infiltration trench or a permeable block/gravel filled grid. If you are worried, put in infiltration crates wrapped in a permeable membrane and run channel drains to this from the front elevation of the garage. www.combinedharvesters.co.uk

Posted: Wed Jun 05, 2013 5:40 pm
by MDay
local patios and driveways wrote:soakaways... 5m from any building 2m from any boundary here in the south east
What if you haven't got any space bigger than those dimensions, and you live in Essex Clay? Seems like the regulations are flawed to me!

Posted: Wed Jun 05, 2013 5:56 pm
by lutonlagerlout
then you use best practise
which means as best is achievable given site conditions

TBH unless its very heavy rainfall very little water off a CBP drive goes down the channels,most gets soaked through

LLL

Posted: Wed Jun 05, 2013 7:02 pm
by dig dug dan
Local enforcement officers here go out on a dry day and pour a bottle of water on new block drives without drainage, then say it a appears to drain through so does not need a drInage channel.
I am starting to wonder if its worth putting in drainage :(

Posted: Mon Jul 08, 2013 10:58 am
by stephen gibson
The "no soakaways within 5m of a foundation" is one of the most confused and miss quoted sections of the building regs.

It's not that straight forward. A normal permeable block paved drive discharges water directly into the ground, which is essentially similar to grass. The natural arrangement for a building foundation is normally to have natural infiltration around it.

When someone puts down an impermeable drive it artificially drys out the ground around the foundation.

The building regs is refering to a soakaway where you are "point loading" water such as a concrete ring system.

The type of soakaway and design is specific to the site parameters. Joe public are best to employ a suitable civil engineering consultant to design them. Compared to the cost of construction work itself, its a minimal cost.

Posted: Mon Jul 08, 2013 5:35 pm
by lutonlagerlout
stephen, joe public dont want to pay for the linear drains let alone the soakaway
do you know any Civil Engineering Consultants by any chance :;):
welcome aboard
:)
LLL

Posted: Thu Jul 18, 2013 6:26 pm
by stephen gibson
Your absolutely right - the answer to all groundworks is get a good designer, a good contractor and who uses good quality materials.

In the long term it the most cost effective solution.

70% of building insurance flood claims relate not to rivers flooding that you see on TV, but to people doing work which then floods themselves or their neighbours.

Perhaps insurers should tighten up claims and refuse to pay out where someone essentially creates their own problem!