Building Near Tree Roots
I think all of us would agree that trees are good for us. We get our oxygen from them, they absorb CO2 emissions, clean the air, provide food, are protection from the elements and are beautiful to look at. We love trees, for good reason as these are just a few of their benefits.
However, there is nothing more frustrating than when you have decided to install a garden building, build decking, build a fence or any other structure in your garden but there is a tree in the way. Maybe you have an RPA (Root Protection Area) or the tree has a TPO (Tree Preservation Order).
Or perhaps you are responsible for the maintenance of a park, or historical site on a conservation area.
You need to have a new building or structure installed but due to the mentioned circumstances, you are very restricted. What is the solution?
In this article, we will discuss the following:
- What is a tree preservation order (TPO)?
- What is a root protection area (RPA)?
- Why do trees need to be protected?
- What solution can Stop Digging provide?
- How does Stop Digging ensure they do not damage tree roots?
- What are ground screws? And what are their benefits?
WHAT IS A TREE PRESERVATION ORDER (TPO)?
The UK government website has a lot of useful information and says the following which you can find here.
A Tree Preservation Order is an order made by a local planning authority in England to protect specific trees, groups of trees or woodlands in the interests of amenity. An Order prohibits the:
- cutting down
- wilful damage
- wilful destruction
of trees without the local planning authority’s written consent. If consent is given, it can be subject to conditions which have to be followed. In the Secretary of State’s view, cutting roots is also a prohibited activity and requires the authority’s consent.
WHY DO TREE ROOTS NEED TO BE PROTECTED?
The tree roots are the part of the tree that is most susceptible to damage during development and construction. This is because of how vital roots are for the health of the tree. Because they cannot be seen above ground, if they are damaged, the effects often cannot be seen for many years and may result in costly tree work in the future.
COMMON DAMAGE TO TREES DURING DEVELOPMENT
Some of the most common damage done to trees includes:
- Abrasion of bark and wounds that leaves wood tissue exposed.
- Crushing of roots by machines and/or storage of materials.
- Severing and removal of roots by excavation.
- Broken branches, leaving wood tissues exposed.
- Poor pruning.
- Fire damage.
- Poisoning of roots from spillage, or storage of fuel, oil, chemicals and any other potentially noxious materials.
- Changes in soil levels around trees, resulting in root death.
- Installation of impermeable surfaces.
Lack of protection can also result in damage to bark and branches that can disfigure a tree and result in disease and decay that also reduces safe life expectancy. Like root damage this is often not seen until long after the damage occurs.
WHAT IS A ROOT PROTECTION AREA (RPA)?
A root protection area is usually an area which is protected to avoid damage to the tree’s root system immediately under and just beyond the crown. It is a layout design tool that shows the minimum area around a tree that is said to contain the right number of roots to maintain the trees health. You will often hear this term used in planning applications but is also applicable in agricultural and forestry situations.
TREE ROOT SYSTEMS
Tree roots are a vital part of the eco-system and have three main functions:
- Absorption of water, oxygen and nutrients.
- Tree ‘food’ storage in the form of starch.
- Structural support.
Tree root development spreads horizontally to a distance and depth entirely dependent upon the ground conditions encountered. Roots require oxygen and water to function and therefore most will remain close to the surface. Research has shown that 90% of tree roots are to be found in the top 600mm of soil. Roots may extend horizontally for considerable distances and, where conditions are suitable, this distance may be equivalent to two, or even three times, the tree height.
Most roots are the easily overlooked, fine, fibrous roots that absorb water, oxygen and nutrients from the soil; these are easily damaged by crushing and removal during soil stripping operations. The main structural support roots are usually found within a few metres of the tree stem and these are linked to the fibrous roots by a network of cable-like roots that also provide additional anchorage. All tree roots are important.
WHAT SOLUTION CAN STOP DIGGING PROVIDE?
Stop Digging provide a screw pile foundation system, sometimes known as ground screws, ground anchors, screw piles, pile foundations etc. There are many different names for a ground screw but these screw piles are a simple and effective foundation solution. Stop Digging ground screws work the same way as a concrete post/block, but without the need to dig and use concrete. Each screw takes just minutes to install and saves lots of valuable time, money, and hassle. Not to mention how much better it is for our environment than concrete. For more information on the environmental benefits see here.
Our ground screws are perfect for supporting timber-framed houses, SIP panel builds and extensions, garden rooms, walkways and wooden paths, decking, fences, flag poles, signs, playground equipment and much more. Stop Digging Screws are widely regarded as a very localised, low impact option upon which to mount structures within an RPA.
The use of handheld hand portable equipment and a no-dig approach ensures that any damage to tree roots is heavily mitigated. This not only protects the major roots (over 25mm) but also the important fibrous root system often found close to the surface.
HOW WOULD YOU GO ABOUT INSTALLING THE GROUND SCREWS NEAR TREE ROOTS AND HOW DO YOU ENSURE THERE IS NO DAMAGE?
The location of the screw piles is important to provide adequate foundation support to the structure, whilst avoiding major tree roots above 25mm in diameter.
The certified and experienced Stop Digging installer will mark out the proposed location of the structure, and the screw pile locations with shallow depth pegs, he will use a metal bar to drive a hole by hand, going down slowly in stages. This will test the location and will allow him to see if there are any significant tree roots in that area. If roots above 25mm in diameter are discovered, then the screw pile pilot hole must be relocated to the nearest possible position that is free of roots.
The experienced installer will carefully pre-drill a hole, ensuring it does not encounter any major roots. The pre-drilling will continue down to suit the length of screw that will be installed with the screw then being installed.
The result of following this method (more information on our detailed method can be found in our method statements) will ensure that all ground screws will be inserted into the soil without significant damage to any tree roots.
Ground screws are suited to a wide range of soil types, with different lengths available for each unique area. Their site-specific load capacities can be assessed by way of a pull, or load test. This involves installing a test screw(s) and assessing their performance. Except for the screw installation, the test is surface-based and completely non-invasive. Each project or site must be treated individually, and we would always advise that an Arboriculturist is consulted. Particular attention must be given if the site has trees with TPO’s (Tree Preservation Order) and the local authority tree officer must be consulted.
Trees are protected and for good reason, these precious giants are becoming endangered but are vital to human life and the health of our planet.
However, there is an amazing solution that means we do not have to place our buildings and structures miles away from the trees. Stop Digging ground screws do not damage the roots and can be placed in a way that means we can build within the root protection area in many cases.
If you would like more information on how we can help you with our innovative ground screws, contact us today on: SALES@STOPDIGGING.CO.UK or 020 3970 3979