I have a wasps' nest (with lots of small normal wasps popping in and out) under my attic room floor. Then I found this. It is about 2cm long and has a yellow face (which doesn't show on this picture). I noticed the black lines on its body are very straight and it is more honey coloured than yellow.
Is it a big wasp or concidentally in the same vicinity as the nest?
I think you are right becaue of the yellow face, the 2 straight lines on the body, and the fact that it likes wasps' nests (!). The only query is size - I see volucella pellucans is about 16 mm and has similar habits so I am convinced.