What if I paint without rendering the wall?

I am planning to have a garden office with thrmo blocks. Both sides has approx 100mm gap against garden walls and will not be able to render as not enough space to get in. Would that cause any problem


if the front and back walls are rendered and leave side wall with just painting (waterproof masonary )?What if I paint without rendering the wall?
must be in the UK,


rendering in the USA means taking something out like rendering the fat out of pork


also most of us use feet and inches not mm .


please restate the ? with more detail using feet and inches


like how big is the Opening ? [door way]What if I paint without rendering the wall?
I have no idea what you are trying to describe here......????
Thermolites are very porous, so you may have damp problems if you do not render all walls. Masonary paint would only be a short term fix, and the wall would need re-painting after 5-10 years which will prove difficult with only a 100m gap.