Shed height regulations

[dsh62]

Can anyone tell me if the 4 metre maximum height regulation for a domestic shed includes a decorative finial - or is an add-on finial exempt from the 4 metre rule?
To elaborate: I have built a pitched roof shed which is just short of 4 metres high, measured from the surrounding ground to the top surface of the lead ridge roll. I want to fix a decorative pointed finial to both the apex bargeboards at each end. These will project another 500mm above the lead ridge roll.
Will this fall foul of the Regs - or are purely decorative finials not-counted?
Oh what I would give for a definitive answer (because my local planning office doesn't seem to know)