Red brick garden wall double skin with moon gate

[Sipherlucian]

Building a 10.1m long redbrick garden wall, double skin, 2m high with 2 brick wide piers on either end same height, with a moon gate in the centre this section will be a 2m diameter so probably an extra couple of courses on top on that section.
I was estimating a foundation of 450mm deep x 650mm wide and starting the wall 200-300mm below final ground level. Does this sound sufficient, would I possibly need another pier either side of the moon gate. Also need to build a matching standalone pier at another corner of the area, 2m high again and 2 bricks wide, what foundation size would someone recommend for this and I assume a rebar column would be recommended? This is a Hobby project and a means to learn so any advice is appreciated .Thanks for any feedback

 

[Bonni]

There are two people in the world, designers and builders. So the builder would build it off plan. The person who designs it would look to see where to put expansion gaps, which brick bond to use, if they recommend rebar then that would designed because throwing rebar in without speccing it will probably be of little use. Then they would advise on foundations to take into account frost heave and soil type.

Then mortar ratio mix, DPC considerations at the bottom and top of the wall and coping/capping considerations.

Without all this, many walls lean and fall to bits. Double skin means 1 brick wall, thickness of the wall is 215mm (the length of 1 brick).