Why not curved lentil as oven opening?

[KISS4me]

Following the information and wise advice from this forum I have completed my base now. See photos at https://www.flickr.com/photos/129613...57715344888848.
I would not advise mixing the perl/verm on a windy day like I did!

[david s]

I hope you didn’t include either vermicrete or perlite in that foundation slab. It decreases the strength of concrete enormously. Only use it for insulation.

[KISS4me]

It may look as though have some of the light stuff in the lower part, but not the case. Bottom half (3.5") is structural concrete with reo bars.