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Planning requirementsplanning_1.jpg

The following sets out our understanding of the current planning guidelines, as set out on the Government’s Planning Portal.

However we advise all customers to take their own advice on planning as every local authority has their own way of interpreting the guidelines. We can prepare and submit planning applications on your behalf, or supply drawings if you want to do the application yourself.

Important: Definition of Microgeneration

It is our understanding that any permitted development rights referred to below for domestic and non-domestic properties are restricted to systems of up to 1 MW.  In particular the non-domestic permitted development right are set out in Statutory Instrument 2012 No 748 Town and Country Planning as relating to ‘Microgeneration’, which has the same meaning as in the Energy Act 2004. The Energy Act defines Microgeneration as being up to 50kWp (for electricity). Thus for systems sized at 1 MW and over, assume you need planning permission

Domestic Installations (Installations on Private Dwellings)

The installation of solar panels on a roof or wall of a private house is considered to be “permitted development” (i.e. doesn’t require planning permission) provided that:

  • Panels should not be installed above the ridgeline and should project no more than 200mm from the roof or wall surface. Note: These conditions will be satisfied if panels are mounted parallel to the roof on a sloping roof. They are unlikely to be satisfied if the panels are mounted on a flat roof, since in this case the panels will be mounted at a minimum 5-10 degree slope to the horizontal and will project more than 200mm above the roof.
  • If your property is a listed building, the installation is likely to require an application for listed building consent, even where planning permission is not needed. We recommend you check all installations with the local planning office.
  • Wall mounted only – if your property is in a conservation area, or in a World Heritage Site, planning consent is required when panels are to be fitted on the principal or side elevation walls and they are visible from the highway. If panels are to be fitted to a building in your garden or grounds they should not be visible from the highway. To be safe we recommend you check all installations with the local planning office.
  • Ground mounted installs will generally need planning permission unless the array is less than 9 square meters, but even then you should check. The portal implies that ‘standalone’ systems (by which we assume they mean ground mounted systems, but it is worth checking with your local authority that this is what they mean) don’t need permission as long as they comply with these very restrictive guidelines:

-no higher than four metres;
-at least 5m from boundaries;
-size of array is limited to 9 sq m or 3m wide and 3m deep;
-should not be installed within boundary of a listed building;
-in the case of land in a conservation area or in a World Heritage Site it should not be visible from the highway.
-only one standalone solar installation is permitted.

Non-domestic installations

New regulations introduced in April 2015 have deemed most non-domestic solar installations below 1 MW as permitted development, provided:

  • panels are kept below 200mm perpendicular protrusion from the plane of the roof or wall (pitched and wall installations);
  • panels are at least 1m from the external edges of the building (pitched and flat roof installations);
  • panels protrude less than 1m from the roof surface (flat roof installations);
  • a ground mounted array is no more than 9m2, no more than 3m in any one direction and no higher than 4m.

Permitted development does not apply:

  • if the installation is on a listed building or on a building that is within the grounds of a listed building, or on a site designated as a scheduled monument;
  • if the building is on Article 2(3) designated land and the equipment is not installed on a wall or a roof slope which fronts a highway;
  • if there is more than one ground mounted system within the curtilage.

For systems greater than 50 kW: the Prior Approval of the Local Planning Authority is required, which is a much less prescriptive process than a planning application. This will assess the design and external appearance of the development, particularly in respect of the impact of glare on occupiers of neighbouring land.

Project timescales

There are three or four hurdles which may need to be overcome before an installation can proceed.

Roof top domestic installations under 4kWp

For domestic roof top installations the only hurdles are usually the structural report and the D-rated EPC requirement. In addition if the system size exceeds 3.68kWp an application to the DNO is usually required if the house has a single phase supply (this limit is 3.68kWp per phase, so 11kWp on a 3 phase supply). Consent to connect to the grid is usually forthcoming for systems under 4kWp.

Allow 4-6 weeks between placing an order and completion of the installation.

Non domestic installations and larger domestic installations

Possible hurdles to be overcome will be as follows:

  • Planning permission (when required) (allow 10 – 11 weeks) If planning permission is required we will usually spend two weeks compiling the application, after which there is usually an eight week wait for the planning department to determine the outcome of the application.
  • EPC requirement This requires us to send a qualified EPC assessor. If the building does not achieve the D-rating required for the full tariff, it may be that minor alterations (insulation) are required. Alternatively it may be possible to route the electricity to a building such as a barn that is non-habitable and therefore exempt from the EPC requirement. Note that schools require an EPC to receive the full Feed-In Tariff, but it does not have to be D-rated.
  • DNO application (allow four to six weeks) In addition to planning permission, installations over 3.68 kWp (on a single phase supply) or 11kWp (on a 3 phase supply) will require an application to the relevant DNO (network operator), such as Western Power or SSE. These are usually decided in four or five weeks, although the network operator does have up to 45 days to decide whether to allow the connection to go ahead or not. Sometimes the DNO will allow the connection to proceed, subject to certain additional costs to enable them to upgrade the grid (transformer or cables) in the area.
  • Additional work to grid/installation of 3-phase connection (allow at least six weeks if required) If the DNO identifies additional work to the grid or if a 3-phase connection needs to be installed on the property, this is likely to add a further six weeks to the timescale.
  • Structural report (allow one to two weeks) The final hurdle to overcome for roof mounted installations is the structural report, to confirm that the roof can take the additional loads imposed by the panels. Additional strengthening work may be required as a result of this report. As long as the work is not major, it can take place at the same time as the panel installation.

We will usually apply for planning permission, apply to the DNO and prepare a structural report concurrently, so that if all goes well, all of these hurdles can be overcome in 10 weeks. We are then free to proceed with the installation, which typically takes place four to six weeks after the planning decision. The installation itself will usually take between one and three weeks, depending on the size of the project, giving an overall project timeframe of around four months.

At the request of the client, and to reduce our costs (and theirs) in the event the planning application fails, we may delay applying to the DNO or preparing the structural report until the planning application is determined. This typically adds an additional month to the proceedings, giving a complete timeframe of five months.

A typical installation schedule for a large scale domestic or non-domestic installation would be as follows:


The install process: managing your installation

Once you have booked an installation the process runs as follows:

  • We will appoint a dedicated project manager to manage all aspects of your installation. Your project manager will be your personal point of contact at Spirit Solar, and you will be able to speak to them whenever you need to, before, during and after the installation.
  • If you haven’t already had a technical survey, we will book a survey on a day that is convenient for you. One of our installers will travel to your property and carry out a full technical assessment.
  • During this survey, we will check your roof to make sure it can support the panel load. We will provide you with structural calculations based from our partner structural engineer. We may need to carry out minor strengthening works to your roof.
  • If the installation requires planning permission and you have asked us to help with this, our planning department will contact you and will gather the necessary information to submit a planning application.
  • We usually install within 4 – 6 weeks of the date on which you sign the installation contract, sometimes sooner, depending on the availability of our installers.
  • If your project requires scaffolding, we will arrange for scaffolding to be put up before the installation begins. During the installation our installers will be on site from about 9:00am to 5:00pm. A typical installation will take two to three days.
  • At the end of the installation our lead installer will fully test and commission the system. We will invite you to inspect all aspects of the work carried out. Our installers will be able to provide a detailed explanation of what each component does and how to operate your new system. You will receive a full handover pack with instructions on how to oversee the system and all the information needed to claim your feed in tariffs.
  • Finally, once you are totally satisfied with your new system, we will send you an invoice for the final balance. (We take a 25% deposit upfront on domestic installations, with the balance due within 7 days of completion.)

As it says in the section on Project Timescales above, for domestic installations not requiring planning permission, you can expect to have your system up and running within about 4-6 weeks of contacting us, sooner if you are in a hurry.