Town & Country Planning (General Permitted Development) (England) - cubic volumes calculations

[Nozzle]

Are there any experts in Permitted Development on here?

Specifically I'm interested in Part 12 "Development by local authorities" and the statement
Class A Part a
"any small ancillary building, works or equipment on land belonging to or maintained
by them required for the purposes of any function exercised by them on that land
otherwise than as statutory undertakers;"

With the added footnote

"Interpretation of Class A
A.1 ....
A.2 The reference in Class A to any small ancillary building, works or equipment is a reference to
any ancillary building, works or equipment not exceeding 4 metres in height or 200 cubic metres
in capacity"

How is the cubic metres capacity defined, simple hxwxd? This makes sense for a cuboid building or similar but how about a skateboard ramp? Which are broad and wide with elements of height, but the overall concrete volume is much less than the basic hxwxd dimensions would suggest. How about when it is partially below ground, does the section below ground not count? I assume it does.

Nozzle

 

[^woody^]

It's the height dimension which is relevant. Height is above ground level.

 

[Nakajo]

I think it would be reasonable to consider the volume as that contained beneath the ramp - just like the area on a graph, if you remember your school days.

 

[^woody^]

I think it would be reasonable to consider the volume as that contained beneath the ramp - just like the area on a graph, if you remember your school days.

So is this a building, works or equipment? I have not got my maths or physics book from back in the day, but I am sure that a volume must be contained. What's the volume of a bridge?

 

[Nozzle]

I would call it equipment.

The basic dims, excluding the earthen banks is 7.5m x 28m x 1.9m - total = 399m^3. Not much of it is below ground - I estimate 5-10%

Planning permission is in, though there is an argument from the council that PP is not required anyway as it's small enough to be done under PD. I think if PP is not granted, they'll go ahead anyway - I also think it's 100% too large.

1.9metre is the highest of the height. The other peaks measure at 1.8m, 1.58m, 1.35m. Taking even the smallest peak the basic box volume without the earth banks is 283m^3.

Taking the volume of concrete only, it's probably only 40m^3. If it is calculated by pure volume alone, then in principle they could cover 36mx36m (150mm deep) and still be under the limit - which seems jolly huge to be PD. For this reason I think it's basic cube measurements.

Is there a guide/bases document that accompanies the Town & Country planning act?

Nozze

 

[Nakajo]

Yes. See the chapter on skateboard ramps.

 

[Nozzle]

Yes. See the chapter on skateboard ramps.

I've searched the PDF for all sorts of related terms, no luck. I've searched the govt. planning website too - no luck. Do you know for a fact there is such a chapter? Please do spill the beans.

Nozzle

 

[^woody^]

GPDO 2015 s4. 2 (1) a
Skateboard ramps, runs, banks, jumps, launchs, grind rails and the like shall be measured by height above adjacent ground level.

 

[Nozzle]

http://www.legislation.gov.uk/uksi/2015/596/pdfs/uksi_20150596_en.pdf <--this is the doc I have, I cannot see this GPDO 2015 s4. 2 (1) a in it...

Though the line you have provided does confirm half of the story, that says anything below ground is exluded from the cubic capacity. I aim to find how the cubic capacity above ground is calculated.

Nozzle

 

[Nozzle]

To clarify my second post above as I think the combination of replies are giving me the impression that my initial post was ambiguous.

The dims quoted (7.5m x 28m x 1.9m) are above ground (399m^3) above ground. There is very little below ground, that which is is additional to the 399m^3

It's taken a bit off faf, but the drawing is now uploaded. A picture = 1000 words

Nozzle