Overriding Justification within BS 5837

[StudioS]

We have submitted a planning application for a replacement dwelling with an attached garage. Part of the garage sits within the RPAs of a Lime Tree and a series of Beech trees (please refer to the attachment). Because of this, we have received a refusal from the Arbroiculturalist advisor within the Council.

 

He stated that the only way to get planning is to either:

 

a) Amend the scheme to remove the garage, or

b) Provide overriding justification for construction within the RPA of the trees, as per 5.3.1 of BS 5837.

 

For reference, BS5837 states:

 

"5.3.1 The default position should be that structures (see 3.10) are located outside the RPAs of trees to be retained. However, where there is an overriding justification for construction within the RPA, technical solutions might be available that prevent damage to the tree(s) (see Clause 7)..."

 

1. Does anyone know of any examples of an overriding justification that has allowed construction within the RPA?

 

Thank you.

 

[Marula]

A quick question, I'm assuming this was done in the correct order starting with the topographical map etc, why with all that information available would an architect stick a building not only in the RPA but basically on the trees?

There are ways of circumnavigating an RPA through different methods of foundation laying, but this plan shown here would require the trees to be removed.

I think the Arb officer was being polite in saying he will definitely not sign off on this.

 

 

[sloth]

There are many examples of installing constructions within RPAs, but in this case there is simply not enough info to make useful specific comments. It seems on the face of it, that the tree officer is being quite reasonable.
G7 is a line of cat C beech, the lime T6, or 3 (4 or 5) and cat B? That is serious pressure on G7 for a start, lots of canopy overhang, massive RPA incursion to the north - what is to the south - will they be under future pressure for removal? Better to remove and replant - is cat C really appropriate, a line of trees or a hedge? T3 looks big, and off site too.
What about buildability? There's a cez in the north east corner, what about to the south of the garage? How will that work in reality?
And then the big question - what about the rest of the site? Is there no scope to re-jig the footprint?
Just initial thoughts there, food for thought. What is your involvement in the planning app, has an arb had any input at any point?
.....

[StudioS]

Thank you for your responses, much appreciated.

 

An initial proposal was created, after which point an Arboriculturalist was instructed to create an AIA, AMS and advise on the scheme. 

 

The only recommendations received were to move the garage further from G7, which was done. The arb made no mention of issues building so close to T3 or T6.

 

Due to the shape and size of the site, there is no scope for re-jigging the scheme. The main house may appear quite large, but it is in keeping with the rest of the area. Planning have stated that there are no issues regarding the size of the proposal, the only problem is the impact on trees. 

 

Please find attached the entire TPP.

[oslac]

Why not construct the garage above the ground. Insert micro-piles which can be inserted under a suitable methodology and construct the ring beam and concrete floor above the existing ground level leaving a void. The issue with the crown is separate but it looks like your arb has stated that only minor or limited branches need removal. I would argue with the TO and say that building above the ground is outside of the RPA. If the TO is concerned about the piles being close to the tree, this can be dealt with (as mentioned) under methodology or cantilever the foundation.

 

I would also ask the Case Officer for the specific reason why this was proposed for refusal rather than a generic comment. 

 

Also and without knowing what T6 is and its visual impact but the tree doesn't look particularly big, you could go for its removal and if necessary replant under a landscape condition.

[daltontrees]

Is there a reason why you are not just asking your arboriculturist to resolve these issues? He/she seems already to have specified non-invasive foundations for much of the garage, and a lot of protection for other trees, and will doubtless have a view on whether the remaining RPA incursions are acceptable. It is for trhe designer to provide overriding justification and for the arb to say how and whether the trees(s) can stand it.

[armybloke]

Consider a cantilever on above ground ground beam installed upon 125mm mini piles hand-machine augured between roots. Diverted rainwater system beneath floating structure and bund accordingly to prevent waterflow escape into living space (outdoor space). So long as you have sufficient canopy to crown lift without inflicting large wounds (progressive pruning over 2 years?) then G7 is provided an opportunity to thrive. A hostile environment change will impact any tree but the species may respond? Is G7 a lapsed managed hedgerow in favour of a group?

[benedmonds]

1 hour ago, EdwardC said:

I can see a number of problems.

 

 

You didn't mention the site is completely enclosed by tree protection fencing... It's going to be a pain to get anything onsite.....

[Gary Prentice]

3 hours ago, EdwardC said:

Are you suggesting that they were going to put it up. Like you say, it's an inconvenience so best not bother.

I always find TOs and planning officers comments about specified fencing and ground protection in AMS's not happening strange. 

 

If they've been conditioned in planning consent, doesn't it come down to the planning authority to police it?  

[Gary Prentice]

13 hours ago, EdwardC said:

Yes. But surely the applicant should comply in the first place. And the vast majority never read past 'Consent is granted...' if they did they would find it said '...suject to the following conditions.' Even if they do they ignore them. That's not the fault of the tree officer.

Compliance by the applicant isn't my point. The planning system methodology is there, through conditions, to ensure compliance. Disregarding conditions can have consequences, but the very people who are in place to police the conditions don't and then complain that the conditions haven't been complied with.

 

When I write a 5837 survey and AMS I include information for tree protection. I include tasks that require arboricultural supervision or input during the construction phases. I also include examples of documentation for proving that this actually happens (sign off reports) Planning consent the application, subject to adherence to the AMS etc and then it seems that boxes have been ticked and everyone will do exactly what they say they will do to achieve the consent.

 

Personally, I do blame the planning authority. If they won't police the planning system, who is expected too?