Is there any kind of law/legistlation/requirement that you MUST have a soakaway?

JBod

JBod

JBod

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Back story:

I am having an extension built, out of all the quotes we had done only one said we need a soakaway and was quite insistent but didn't really give me a reason. Google results talk a lot about people getting soakaways but I can't find anything anywhere that says why you MUST have one.

He was quite an old guy, I didn't really get on with him and his sales tactics (seemed to rely on scare tactics along with only his 40 years in the building trade would solve all the problems). He is very close to retirement age and I think is a little out of touch.

But I am worried that he may actually cause us problems later on when he discovers that we have already gone ahead with the building work and his quote hasn't even turned up yet. I phoned him up several times asking for any info on the quote and each time he just goes "I work at my pace!" which is not useful when I tried to explain time restraints (pregnant wife etc..).

Actual Query for OCUK masses:
Is a soakaway ever lawfully required? Either by legislation or building regs or by insistence of the water board or ... ?? A drain pipe needs to be moved in order for the extension to go on, it currently disappears into a hole in the ground.. no idea what into (could be a old soakaway for all I know).

At the moment I have agreed with the current builder for rain water from the roof to drain on to the garden which slopes down away from the house, there will be no pooling etc.. and there are no big slabs of concrete (other than the new extension of course) for it to collect on and prevent it from entering the water table.

Thanks o great collective hive mind of OCUK for any insights :)
 
Surely you'd be better off either speaking to the architect or the council's planning/building regs department??

And if you are unsure about the guy, don't use him. Shop around, don't go for the rock bottom price and fingers crossed, it'll work out :)
 
AHarvey said:
Surely you'd be better off either speaking to the architect or the council's planning/building regs department??

And if you are unsure about the guy, don't use him. Shop around, don't go for the rock bottom price and fingers crossed, it'll work out :)
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I've tried, and I have done my online research. They are all sketchy unless you pony up the £££ to find out. And the single builder come surveyor who came round and mentioned it wouldn't even discuss it properly with me (thus me thinking it was just a way to increase the cost of the build).

Even the official building regs say "Surface water drainage should discharge to a soakaway or other infiltration system where practicable.". Soakaways when built MUST be 5metres away from any dwelling or highway which means it can't be built at any point in my garden anyway. Also as it slopes away from my house I can't see why one would be needed?
 
In Scotland at least there is no requirement to have a soak away for rain water. It is now almost impossible to obtain permission to discharge a new septic tank into a water course. If this is the same in England, it may explain the builders confusion.

If the surface area of your extension is very large, there is the possibility that building control could force you to have one. Personally I would not bother to tell them, if them come back a t a later date, you can always put one in.
 
Well you must have architects drawings, yes?
Have you got planning permission?

Then building controls job will be to see you are doing everything by the book.
 
Soak Aways may be required by local building requirements.

Draining onto the back garden isn't always a great idea as it can get waterlogged when there is heavy rain/cause issues.
A proper soakaway is basically a hole in the ground, filled with various levels of filter material (small rocks, sand etc) to let the water get into the ground (under the surface level) as quickly as possible and still filter it.

The reason they may be preferred to just putting it straight into the sewer is due to the load on the local drainage system, and putting it back into the ground locally helps prevent issues downstream (IE you're putting it back roughly where it would have soaked in anyway, rather than along with thousands of other houses).
 
To be honest it sounds like the extension has not been properly planned and this is why there is confusion. Your architect should have everything needed for building regs on the plans including whether or not a soakaway is required.
The builder then gives you a quote based on the plans.
 
You wont always necessarily get full plans approval for an extension, it totally depends on what the appointment was to the Architect (if he even used an Architect).

It could be Permitted Development, which requires little more than a fag packet scribble, with a Building Regs app done via a Building Notice (so long as there are no Part B implications).

Which ever it is, Full plans Submission or Building Notice your best bet is to speak to the Building Control officer and establish what the requirements are in your are, Ive known some to want a soak away and others who aren't fussed and will let you (providing its not huge additional areas of roof area) discharge into an existing system. As for a contractor causing you issues, how can he if your doing everything by the book with your local Building Control officer on board and all applications made ?

Out of interest what is your problem with a soak away ?
 
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peter_hutson said:
I just re-read this bit. I would have thought your garden would count as an "other filtration system". Can't you just discharge in the the sewer?
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Surface water and sewage are discharged separately, and by "other filtration system" it would mean something along the lines of a SUDS drainage system.

Hikari Kisugi said:
Indeed, do you have approved stamped plans and planning permission?
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Planning drawings will more than likely have no drainage details and the application could be as brief as just saying *drainage to be as existing* If no working drawings have been prepared and you are going design and build a competent contractor should advice you on what is best.

From experience you should speak with your area water board as they will advice you if there is a surface water drain to your property and if you are able to add additional discharge to it and if not they will more than likely advice you that a soakaway is required.

Unless you can connect to an existing surface water system; you should be using a soakaway or other drainage system and not discharging onto the garden.
 
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Fact is in England the last Building Regulations state you must have a soakaway unless you can prove that your ground does not allow for the water to drain away fast enough. There's a test involved with digging a certain size hole, putting a known quantity of water in and timing how long it takes to drop by half.

If you don't have one and need one,the building inspector will not sign off on your extension.

I had a massive row with ours and because of the size of the extension and where the drain pipes were, it would have meant all the water from the existing house roof and extension would then be going into a soakaway as all the guttering fell towards the extension and the downpipes were already there. The soakaway was massive as well something like 3m x 3m x 1m.

Then I remembered we got planning permission before the new regs came in and hence only the older building regs were applicable. When i challenged him he sais "well I would still like you to put one in but I can't force you" hee hee. He was not amused when I plumbed the rainwater all into the sewage pipes.:D Of course you are not allowed to do that anymore.

Anyway, your other builders are probably relying on the fact you are just moving an existing one and nobody would ever know it hadn;t been there the whole time. We used that trick on lots of things which got moved before the building inspector came to site.

To be sure, ring the local building officer and ask. Problem there is that if he says yes, there will be no just moving it and pretending it was there all along and you will have to have one put in.
 
Greebo said:
There's a test involved with digging a certain size hole, putting a known quantity of water in and timing how long it takes to drop by half.
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Aye the contractor should be able to carry out percolation tests to determine the rate of surface water run off and the size of your required soakaways.
 
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first of all, it sounds like you had a lucky escape with that old builder.
if it takes him that long to give you an estimate, imagine how long it would take to do the extension at "his pace" :D

i used to work for a builder and now i am a block paver (driveways, and no i am not a gypsy) :p

if there is an existing soakaway there, then you can join to this, but a responsible builder will check the soakaway, to make sure it can handle the extra water.
if it can't then its often easier to just dig a new soakaway. maybe this is what that builder wants to do.
also soil conditions make a difference to the dimensions of this.

you are not allowed to flow surface water to the sewers. it has to go to either an existing rain water drain or to the soakaway.
you could before the new legislation, but then you had to install a trap, to stop the smell from coming back up the pipe.

also now with driveways.
if you are having a new driveway and your driveway flows away from the house to the footpath, then you need to install drainage to stop the water flowing out to the road.

if you are digging out garden area to make your driveway bigger, then you are "supposed" to put in a porus driveway, so the water can soak through the blocks.
but you can get away with using the drains at the entrance instead.
 
To try to answer all the questions in one go.

It is a permitted development (no planning permission needed - have checked with local council) and a tight budget. I am not going to pay for an architect to draw up 3 walls and a few windows. As already pointed out they are not experts on building regs etc.. so they wouldn't know the answer to this question either. I am in no way an expert but I have drawn up precise drawings showing measurements, wall thickness and window placements.

The Build Notice has been submitted and accepted, first visit is tomorrow to inspect footings.

My issue with a soakaway is that it would be £1000+ more on top of what we are already spending for absolutely no gain at all. The extension is 3metre deep and 5 metre wide, the total area is tiny and is in fact replacing an existing conservatory in the same location.

The garden slopes away and down from the house so there would be no problems with pooling water. Having seen the excavations today for the footings it is in fact very solid clay anyway the chances of a soakaway working is slim.

We had a driveway built last year out the front of the house which slopes towards the building, but there is a few metres of garden between the driveway and the house, we were told at the time this is adequate. Would their really be different rules depending on what is built? I think the driveway surface are is in fact larger than the roof of the extension.
 
right, where is the rainwater from the existing conservatory discharging to ?

If it were me I would be looking to argue the case of not having one if you can prove to the BCO that what you are building is not collecting any additional rainwater than what was already being discharged from the conservatory. This really is a question for your BCO to advise on tbh.

That said, a grand seems mental tbh for what in essence is a large hole full of gravel :p

with regards hard standing, you need planning permission now for anything over 25m/s iirc and again it needs to drain off to a soak away, hence why (other than the secure by design compliance) gravel driveways are all the rage again :)
 
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