ToughButterCup

It might be a bit easier than our local tame Overthinker (above @Russell griffiths) thinks ... The water company will give you a specification to which you have to lay your pipe. That's a given. (600mm locally) You will also have an invert level for the foul drain outflow from your house, and a target invert level for the sewer (or treatment plant) to which you want to connect. Assuming (at a guess) you want a 1 in 60 or a 1 in 80 slope (17mm or 12.5mm per meter respectively) then it should be reasonably easy to calculate whether the two services will bump into one another vertically. In our case the invert for the foul drain was always much deeper than 600mm (at least 1330mm below ground level). So, if we had to put both services in one trench, then we could always have separated both services by at least 500mm vertically. Dont forget the warning tape.....? ... like I did.

How exposed is your property to wind? We found that battens - in some places - weren't enough mostly where the local configuration of the build accentuated the wind effect. It was its lifting effect that caught us out. Annoying really because I should have seen that coming - done quite a bit of sailing and flying. I solved the problem by using tie-downs fastened to two or three eye-holes in the edge of the tarpauline (tied to just one, the rope ripped out PDQ). We made the tie-downs out of old mayonaise tubs filled with concrete, and then stuck a dog tie-down in the wet concrete. The handle of the tie-down makes it very easy to lift, reposition and fasten a rope or ropes. Keeping the covering material taught is an art: its like timming a sail or a wing. It needs constant attention. When I forgot about it, the ceaseless flapping drove me nuts. Especially when the wind decided to blow at 3 in the morning.

Deciduous trees will be the main annoyance if you do.

+ 1 to all that..... And if I may add this cautionary tale - think about how to fit the last joists.

My wife just smiled (code for appalled - on some days - only just starting to learn which ?)

Well Gary, if you two can't do it at rock bottom prices, nobody can.

You ask about delivery of web joists to France. I'm willing to bet that the delivery costs from the UK will exceed the 'cost' of finding a local supplier.

Bienvenu! I wonder if you would be kind enough to use a sans serif font ? I ask because sans serif fonts make legibility easier for all. Verdana is a commonly chosen font - it was designed specifically for on screen viewing.

Her Indoors lifted most of ours. There's something about self-building that flips my Just-Bloody-Do-It switch . And yours @LA3222... Not everyone on site has one. Funny that innit?

Blokes lining up to compare things.... ya couldn't have guessed could ya?

@Russell griffiths, @scottishjohn, @MortarThePoint, thanks very much. I've had each of your ideas, but knowing that I know just enough to be a danger to local shipping , it's extra good to read your posts

It's part of the foul drainage run ....

Alright you lot - how much trench ramming is just enough trench ramming , eh? Tell me that. How do you know when to stop?

Normally I love whacking. Find it soothing. Occasionally a filling falls out , but what the heck. You end up with a nice smooooothe surface. Now when @Mr Punter writes this, (here) I sit up and take notice. The word probably might be important innit? I've backfilled .... like this gone is the sheer cliff face, insted, theres this 40 degree 'slide' - had fun rolling the glacial till boulders downhill.... And of course @Mr Punter is right: it needs compaction. Now I never was Charles Atlas, or Geoff Capes - but Hell even those two would have found pulling or pushing a whacker up that slope a bit of a challenge. Do I have to hire a fiver tonner and thump that sloped bit of the trench hard with the bottom of the bucket? And once I have, how on earth do I get 100mm of gravel to sit nicely on the slope at 40 degrees?

Well Gary, gotta hand it to you. The only man IN THE WORLD who can put scaffolding through a pane of glass without breaking it.

Interesting. I haven't seen a domestic tank quite that big. 10000 litres is small swimming pool size. Quite some effort will be needed to maintain that amount of water in a usable condition. Unless the local geology is on your side. But if it were you're not likely to be asking us for advice. Sounds like a job for 3 or 4 5000 litre tanks . When I last looked, and decided against, a 5 thousand litre tank was about £600. It was the cost of the surrounding infrastructure that ramped up the total cost so much that the project was shelved. Unless a farmer was getting rid of a tank......? That might make it worth reconsidering. But I still hanker .... I really like the idea.

There isn't a recommendation. The depth has to be just enough.

Hilliard Tanner designed ours. His careful engagement with our site conditions enabled us to save about 17 thousand pounds on the costs associated with piling. He need not have pointed out that the piling system suggested by the geophysical surveyor were an expensive way of supporting the raft. In addition his colleague Nick Bailey helped us with steels and glulams. A very good partnership.

One of the benefits of deep glacial till, covered by a meter of MOT1. Sits there like a brick outhouse.

I have a quadriplegic mate. No question of not catering for him on our build. Got as much fizz, vim and vigour in him as anyone I know. You can reach out and warm your hands on his enthusiasm.... He's taught me so much about being inclusive. It's essential. Take pride in building your ramps: you might need one sooner than you think.

Overthinking on my behalf is allowed . ? Fanx. "Trench compactor" = wife? Wassa chances of that then?

Exactly. Know-Nowt strikes again: or at least I now know, that I know just enough to realise that I'm a danger to shipping on the site. Time for a chat with the BCO.

Bang on, well observed. No. It is what it is. A friggin nightmare. But Hell, I'm learning fast. After four years I've learned to take a joke.

Where did I find it? Wavin brochure! Thing is , the main drop ( 2meters vertical) occurs over about 2 meters horizontally ... maybe a bit more. Which is 1:1 innit? Backdrop with a rest bend?

I wish I could sort this problem out with one of Billy Connelly's Jobbie Wheechas: but "ah caanee, hen." (tr. from the Scottish : I couldn't possibly do that, dwaahling). Look at this. The flow is from the I/C at the back towards the viewer standing next to the 'top-of-the-drop' - the white topped shuttering. From there it goes .... off down to the digester ( green thing at the back) - about 8 meters. The drop's not far off 2 meters, from top invert to bottom invert. The banking in which it sits is no more than 40 degrees Backdrop? OR 45 degree Helter Skelter as @epsilonGreedy would put it?