Thanks BILLK and HOOP-
Hoopman -
Can't allow 4-6 inches past the end piers as the wall is going from concrete shed to house
All these figures and dimensions are hurting my little brain - on the upside
got a price of €180 for ready mixed concrete(1cu.m) delivered and €150 for the labour- everything has to be ready for him to just come in and lay the bricks
Also, a DIY book told me that if the trench gets flooded by rain I've to seek professional help- this has happened twice in a small section- What should I do
Don't worry about extending it past the end of the wall where its going to come up against another wall. Just extend it where you can.
For example the foundation for the middle pier/piers should extend to be 4 to 6 inches at both ends of the pier. I.e your pier will be 440mm or 400mm long depending on what blocks you are using and so your foundation will 740mm or700mm long. and the end piers that are coming up against another wall should extend 4 to 6 inches at one end only.
As for the flooding, for a trench that size and deep it should be possible to empty the trench of water using a bucket or small paint tin, an hour or so before you pour your concrete.
Good luck in pouring your foundation, did you double check them block sizes are they the metric size ones.
KOH
My views are coloured by the reports in the press over here about the 3 year old girl killed by a wall falling on top of her.
Billk I understand your concerns about walls falling over. and God knows there are enough cowboys getting away with building sub standard structures over the years.
But for a wall that is only 14 blocks long, one in the middle and one at both ends is sufficient enough, unless the building regulations and recomendations have changed since my building days.
Which they may well have as it is a long time since i have had to do it for a living, Thank God.