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03-06-2007, 19:46   #1
sas
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What determines finished ground level?

Hi,

1 part of the house we've gotten planning for has a specific height to the roof peak from finished external ground level.

What determines finished ground level? Is it relative to the road for example?

Is there a rule of thumb? What sort of wiggle room would you have on this realistically?

thanks

SAS
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03-06-2007, 20:36   #2
smashey
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When the application was submitted, did your site layout include a survey/spot levels? Ground level would be derived from this, based on a level taken from the road.
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03-06-2007, 20:57   #3
seabee
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the ground level outside is typically 150mm below the finished floor level of the house.
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03-06-2007, 21:19   #4
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Quote:
Originally Posted by smashey
When the application was submitted, did your site layout include a survey/spot levels? Ground level would be derived from this, based on a level taken from the road.
No. Nothing of the sort.
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03-06-2007, 21:20   #5
sas
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Quote:
Originally Posted by seabee
the ground level outside is typically 150mm below the finished floor level of the house.
Thanks but this doesn't answer the question. What determines where your finished floor level should be?
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03-06-2007, 23:08   #6
muffler
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Quote:
Originally Posted by sas
Thanks but this doesn't answer the question. What determines where your finished floor level should be?
Im not being flippant here but which question do you want answered - Ground level or floor level? You have changed the question over the last couple of posts
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04-06-2007, 00:02   #7
dolanbaker
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On my planning application I submitted a finished floor level relative to a position in the centre of the road, fortunately for me the road slopes slightly, so I could (if needed ) position the FFL at the EXACT height as specified in the plans.

My local CoCo stated that the house shall not be placed such that the FFL is more than 300mm above the undisturbed original ground level.

or words to that effect (I don't have the document to hand)
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04-06-2007, 09:52   #8
sas
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Quote:
Originally Posted by muffler
Im not being flippant here but which question do you want answered - Ground level or floor level? You have changed the question over the last couple of posts
Sorry, thats not what I intended. I see it as having asked the same question in a different way. i.e. Something ultimately determines what the external ground level should be and I would like to know what that is. Seabee response suggested that your ground level is determined once you determine where your finished floor level is, so asking how you determine finished floor level still gets me the same answer. Finished floor level and external ground level aren't mutually exclusive as a general rule I imagine.

Is ground level 150mm below finished floor level with the finished floor required to be measured from some specific point?

Whats the main factor assuming there is nothing in the application or planning permission grant about this?

Last edited by sas; 04-06-2007 at 10:22.
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04-06-2007, 10:22   #9
muffler
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Well you did ask 2 completely different questions and in all honesty you still havent made it clear which you want answered and in any event you are going arseways about determining ground level.

Ground level is whats there before you start to build a house. You are normally asked by the planners to show the proposed finished floor level (ffl) relative to a O.S. bench mark or a temporary bench mark (tbm) established at a fixed point on the adjacent road.

In order to determine your ffl you first of all need to find the levels of the ground for the footprint of the house. Assuming there is no cut and fill involved you would normally set your ffl as being approx 250mm above the existing ground level. As dolanbaker said it will be a condition on the planning that the ffl be no more than 300mm above the lowest point of undisturbed ground level below the footprint of the house.

On the other hand if you are asking what the difference should between the ground and floor levels then it is a min. of 150mm measured from dpc level.

Hope this explains the situation
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04-06-2007, 10:44   #10
sas
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Quote:
Originally Posted by muffler
Well you did ask 2 completely different questions and in all honesty you still havent made it clear which you want answered and in any event you are going arseways about determining ground level.

Ground level is whats there before you start to build a house. You are normally asked by the planners to show the proposed finished floor level (ffl) relative to a O.S. bench mark or a temporary bench mark (tbm) established at a fixed point on the adjacent road.

In order to determine your ffl you first of all need to find the levels of the ground for the footprint of the house. Assuming there is no cut and fill involved you would normally set your ffl as being approx 250mm above the existing ground level. As dolanbaker said it will be a condition on the planning that the ffl be no more than 300mm above the lowest point of undisturbed ground level below the footprint of the house.

On the other hand if you are asking what the difference should between the ground and floor levels then it is a min. of 150mm measured from dpc level.

Hope this explains the situation
Got out of bed on the wrong side did we? The question was what determines the external ground level once the build is finished. 1 of the responses I got stated that finished floor level is 150mm above ground level. Its not a huge leap for someone who doesn't know much about it to the assume that finished floor level is now somehow relevant!

Anyway I've got my answer i.e. external ground level on the site post build should be the same as it is now i.e. a field. Regardless of how much clearing\excavating is done during the build. This is where I wasn't sure.

Incidently there is nothing in my planning permission about ffl.

Thanks

SAS
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04-06-2007, 11:55   #11
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[QUOTE=sas]Anyway I've got my answer i.e. external ground level on the site post build should be the same as it is now i.e. a field. Regardless of how much clearing\excavating is done during the build. This is where I wasn't sure.QUOTE]


Thats about as clear as mud. What are you saying here - if you are on a sloping site and have to excavate the ground then you reinstate it again to where it was?

Your ground level upon completion of the works will have to be at least 150mm below dpc level and not finished floor level as was stated by someone else

Oh, and I wouldnt go making snide remarks at people who are trying to answer your questions. You should know the rules by now. Dont attack the poster. I will let you off with a yellow card this time.
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04-06-2007, 15:39   #12
sas
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Clarification

1 part (1.5 storey) of our house we have obtained planning premission for shows a measurement of 7633 mm from the ground to the peak of the roof on an elevation.

The site is pretty much level and is approx 1 ft above the road level. There is a drain separating the site from the road. The road is also pretty much level.

I was wondering from where the measurement of 7633 is taken with reference to?

Am I missing something fundamental here? There is nothing in the planning application or grant that refers to levels.
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04-06-2007, 16:41   #13
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That would be your ridge height taken from ffl.Your ffl would be referenced from a datum point [centre of the road outside your site] normally given a figure of 100.So your ffl level might be 101.85 for example, meaning it is 1.85 metres above the datum point on the road.
Thats how i read it from looking at my own drawings.

Last edited by bakerbhoy; 04-06-2007 at 16:44.
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04-06-2007, 16:59   #14
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Check your application on-line. There should be some mention of this.
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04-06-2007, 20:07   #15
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Quote:
Originally Posted by sas
I was wondering from where the measurement of 7633 is taken with reference to?
This could be taken in two ways. It is either the height of the ridge from the ground level in mm. This will be shown as a dimension line with 7633 as the text. This way means that the difference in height between ridge and GL is 7633

Or it could be a spot height relating to the TBM, or datum height. In this case the height will be marked at the ridge, there will be similar heights at first floor level, and ground floor level, and also at ground level. This way means that the difference in height between ridge and GL is 7633 - (marked height of GL)


The difference in height between ground level and finished floor varies. 150 is an average. This height will be shown on the section. And as muffler said only the DPC needs to be 150 above GL. Grond level and floor level could, with the right detailing, be at the same level or say only 25mm apart.

Last edited by Mellor; 04-06-2007 at 20:16.
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