Building near TPO trees

[MrJuice]

I'm considering building a classroom at the back of the garden for my son who has autism

Back of the garden has an enormous TPO tree and there's another about 15 metres away

I'm thinking something new age that will be quick to construct. I've seen various piling type foundations used on grand designs but never paid attention to exactly what they are and why they're uses

What building options would the ph massive suggest?

Width is approx 9 metres I think. Possibly 11. To get a decent depth, it'll be going through planning I think

[CharlesElliott]

It's not a direct answer to your question, but if your building needs to go through planning then they will certainly ask for an arboricultural assessment, which will detail the potential impact of your build and the precautions you need to take. The assessment will cost a few hundred quid, and then you will need to pay our for protective fences and a consultant to brief the builders etc. before the start. This will all be a condition of planning.

The impact will depend on the type of tree, how the roots spread etc.

[Muncher]

Your first step should be to get an arboricultural consultant in to advise, if you are going through planning their report will be key in getting it designed and passed. There are various mitigation measures, but you need to know what you are dealing with first. It may be that the root protection zone is so large that your proposed building interferes with such a small proportion of the root protection zone that a conventional foundation may be appropriate.

[MrJuice]

Cool, noted

Thank you

[blueg33]

Might be worth you looking at ground screws. My tech director is on paternity leave, but he was looking at ground screws for our new build houses near trees (he is a structural engineer )

[Equus]

Muncher said:

Your first step should be to get an arboricultural consultant in to advise...

In terms of the building's influence on the tree (as opposed to the other way around), it's not rocket science to establish the likely 'root protection area' yourself, as a first step before involving an arb consultant. Look up a copy of BS5837-2012, which gives you the formula and a handy look-up table (basically a calculation based on the trunk diameter of the tree). It's actually not a complicated or particularly technical document to read, so you might find the other information that it contains is also helpful.

The basic recommendation in the BS is that you can have a ground-bearing slab for a minor structure (such as a shed) covering up to 20% of the RPA, but if you get that far, it probably is time to get an arb consultant involved (or to try to blag specialist advice from the Council's Tree Officer).

Regardless of whether you go through Planning or build something that complies with Permitted Development, you can get a seriously slapped wrist if you harm a TPO'd tree, so you may consider it best to be careful, regardless.

As blueg33 says, there are all sorts of screw pile and non-invasive foundation systems that can be used with lightweight SIPs panel or timber frame buildings, so there's bound to be a solution.

[DozyGit]

How big is this classroom going to be?

I personally would not bother with a foundation. Just get a steel frame building aka container type thing and place it on concrete pads with screw jacks etc to adjust for sinking of pads and rock on.

You won’t need this forever would you? Just get rid once done. These containers come flat packed, you can take it via side access. Just insulate, maybe clad it with something nice like timber or composite panels.

[blueg33]

DozyGit said:

How big is this classroom going to be?

I personally would not bother with a foundation. Just get a steel frame building aka container type thing and place it on concrete pads with screw jacks etc to adjust for sinking of pads and rock on.

You won’t need this forever would you? Just get rid once done. These containers come flat packed, you can take it via side access. Just insulate, maybe clad it with something nice like timber or composite panels.

That would be a criminal offence if it is in the root zone.

You cannot increase the ground load in the root zone. As developers we can’t even store things there, it’s why root zones are fenced off on development sites with TPO’s

Edited by blueg33 on Saturday 7th December 11:07

[Equus]

blueg33 said:

You cannot increase the ground load in the root zone.

Not without permission, that is...

Actually, the offence is to willfully damage or destroy the tree, so they'd have to prove that increasing the ground load (or other activity) had done damage.

But it's a risky/stupid thing to do, without the necessary permission.

LPA Tree Officers are quite frequently more helpful and pragmatic than you might imagine, though, so can be worth having a chat to them.

[Vincecj]

Depending on the size, what about a shepherds hut? Less planning implications. We've just built this for a client.

[MrJuice]

Equus said:

Not without permission, that is...

Actually, the offence is to willfully damage or destroy the tree, so they'd have to prove that increasing the ground load (or other activity) had done damage.

But it's a risky/stupid thing to do, without the necessary permission.

LPA Tree Officers are quite frequently more helpful and pragmatic than you might imagine, though, so can be worth having a chat to them.

Can't believe how long this is all taking.

But anyway, tree officer was indeed very helpful and pragmatic. There's only one for the whole local authority and so I sent her pictures, scaled drawings and written descriptions of what I want to do to help.

She agreed that beam and block construction of a 30sqm outbuilding within the root protection area of three TPOd trees would be okay. The building would be at least 6-8 metres from each tree.

Just waiting for party wall agreements and should be cracking on in a few weeks.

[DBSV8]

Vincecj said:

Depending on the size, what about a shepherds hut? Less planning implications. We've just built this for a client.

If i was a neighbour id be pissed with that overlooking my property

[Evoluzione]

DBSV8 said:

Vincecj said:

Depending on the size, what about a shepherds hut? Less planning implications. We've just built this for a client.

If i was a neighbour id be pissed with that overlooking my property

I'm one of the last people to ask about the legalities of planning so more for conversations sake, if it hasn't got windows on that elevation, then perhaps it isn't overlooking.
Also, I thought they were easy to put on land without much, or any permissions because they were on wheels, therefore could be moved. That one clearly isn't.....

[Equus]

Evoluzione said:

I thought they were easy to put on land without much, or any permissions because they were on wheels, therefore could be moved. That one clearly isn't.....

They have to comply with the definition of a 'caravan' under the Caravans Act, but oddly enough, that doesn't require them to have wheels.

[Evoluzione]

Equus said:

Evoluzione said:

I thought they were easy to put on land without much, or any permissions because they were on wheels, therefore could be moved. That one clearly isn't.....

They have to comply with the definition of a 'caravan' under the Caravans Act, but oddly enough, that doesn't require them to have wheels.

That's interesting and something i'll have to follow up now I know the terms.

Is there also some law which states you can put something in a field for X amount of weeks per year without PP? It would need wheels then....
I'm just exercising an idle plan to put a portable holiday let in a field.

[Equus]

Evoluzione said:

That's interesting and something i'll have to follow up now I know the terms.

To save you the bother:

Caravan Sites and Control of Development Act 1960 said:

“caravan” means any structure designed or adapted for human habitation which is capable of being moved from one place to another (whether by being towed, or by being transported on a motor vehicle or trailer) and any motor vehicle so designed or adapted, but does not include—
(a) any railway rolling stock which is for the time being on rails forming part of a railway system, or
(b) any tent;

Is there also some law which states you can put something in a field for X amount of weeks per year without PP? It would need wheels then....
I'm just exercising an idle plan to put a portable holiday let in a field.

That's the '28 day rule', but 'caravans' are among the specific exclusions.

There are other 'loopholes' that can be applied to caravans, but the legislation is a bit of a minefield, so you need to take specialist advice - I'm not expert in it myself, so even I would refer it to our Planning Director (who is).

LINK

LINK

Edited by Equus on Tuesday 7th February 11:53

[guitarcarfanatic]

Build a garden room under PD (assuming you have it). Check out Oakwood Garden Rooms on Youtube. His method is to create a series of holes with concrete and threaded rods/plates for the joists to sit on. The room is then constructed like an American timber building (framed, osb clad, membrane, batten, cladding). He fit's big aluminium bifolds with either a steel or a flitch beam etc.

I built my workshop in a similar way, just on a solid pad as it was already there.

[DBSV8]

Evoluzione said:

DBSV8 said:

Vincecj said:

Depending on the size, what about a shepherds hut? Less planning implications. We've just built this for a client.

If i was a neighbour id be pissed with that overlooking my property

I'm one of the last people to ask about the legalities of planning so more for conversations sake, if it hasn't got windows on that elevation, then perhaps it isn't overlooking.
Also, I thought they were easy to put on land without much, or any permissions because they were on wheels, therefore could be moved. That one clearly isn't.....

it has according to the web page



in keeping in a ruddy field but not in a housing estate