Conditions requiring approval of materials and samples
Approval of external materials under a condition is a consent in its own right. Here is what the condition requires, how sample panels work and what to do when a product has to change.
A materials condition planning approval is a separate consent, and treating it as paperwork is how build programmes slip. The condition requires samples or product details to be submitted to and approved in writing by the local planning authority, and until that approval is issued the relevant works cannot lawfully proceed. The authority has up to eight weeks to determine the request, there is a fee, and on a heritage site the conservation officer will want a panel built before deciding.
Architects who front-load this at the drawing stage rarely have a problem with it. Those who leave it to the contractor discover that the brick with a 16 week lead time was not the brick the officer approved.
Why authorities condition materials
Because appearance is a planning matter and materials are usually not fixed at application stage.
An officer assessing an elevation is judging proportion, rhythm, depth of reveal and material character. Where the application says "brick, to match existing" or shows a hatch with no specification, the officer has two options: refuse for lack of information, or grant and condition the detail. They condition it.
National guidance on the use of planning conditions requires each condition to be necessary, relevant to planning, relevant to the development permitted, enforceable, precise and reasonable. A materials condition passes those tests comfortably where the materials are unresolved, and fails the necessity test where the drawings already specify them. That is the first argument to have.
There is also the question of timing. Under section 100ZA of the Town and Country Planning Act 1990, a condition that has to be discharged before any development begins cannot be imposed without the applicant's written agreement, under the procedure in the regulations made for it. Most authorities now draft materials conditions to bite before above ground works rather than before any work starts, which is both more workable and less contentious.
What the condition usually requires
Read the wording rather than assuming. The variants matter.
The narrowest form requires details or samples of specified elements, typically facing brickwork with mortar and jointing, roof covering, window and door frames and their finish, rainwater goods and boundary treatments. The broadest form requires "samples of all external materials", which on a mixed-use building is a large submission and a slow one.
Two drafting features to look for. Whether approval is required in writing, which it almost always is, and whether the condition says the development shall be carried out in accordance with the approved details, which ties compliance into the permission permanently.
Then check what triggers it. Before any development starts. Before above ground works. Before the relevant part of the works is begun. Before first occupation. These are very different obligations, and a condition tied to the relevant part allows you to phase the submissions rather than approving everything at once.
Where an application already specifies materials on a drawing, ask for the condition to refer to that drawing. A permission recorded on the statutory planning register with a materials condition that duplicates the approved drawings creates ambiguity you will spend time resolving later.
Sample panels on site
For brick and stone, a physical panel is usually expected, and on heritage work it is close to universal.
The normal ask is a panel of around one square metre, built on site in the proposed brick with the proposed mortar mix, jointing profile and bond, in a position where it can be seen in daylight against the existing building. It is inspected, approved, photographed and then retained until the relevant works are complete so the contractor and the officer have a reference.
What makes a panel fail inspection is rarely the brick. It is the mortar colour, the joint profile, or the bond not matching what was drawn. On a conservation area or listed building job, lime mortar specification and the treatment of the joint carry as much weight as the brick itself, and that discussion belongs in the Heritage Statement at application stage rather than in a condition discharge six months later.
Three practical points. Build the panel before you submit the discharge application, so the officer can inspect on their first visit. Build it in the right orientation, because a north facing panel reads differently from a south facing one. And agree in advance who inspects, since a conservation officer's diary is the constraint on heritage sites.
Timing against the build programme
Work backwards from the day the bricklayers arrive.
The sequence is: select the material, obtain the sample or the product data, build the panel where one is needed, submit the discharge application with the fee, allow up to eight weeks for determination, allow for the officer's site visit and any request for a revised panel, then procure. Brick lead times sit on top of that, and specials and cut bricks extend them.
Two levers shorten it. Submit early, because nothing prevents a discharge application being made as soon as the permission is issued. And submit a complete application, which means product data sheets, a specification, photographs of the panel and a drawing showing where each material goes, rather than a covering letter naming a brick.
Where the authority has not determined the request in time, section 74A of the 1990 Act allows a deemed discharge notice to be served for qualifying conditions, with certain types excluded by regulations. It is a useful backstop and a poor primary plan, because a deemed discharge of a materials condition leaves you building to a specification the officer never saw.
Substituting a specified product later
This happens constantly. The approved brick is discontinued, the lead time doubles, or the price moves.
The route depends on how the specification is fixed. Where the material was approved under the materials condition, a further submission under the same condition is usually the answer, with a comparison against the approved product and, where the difference is visible, a fresh panel.
Where the material is named in the condition wording itself, changing it means an application under section 73 to vary the condition. Where it is named only on an approved drawing, a non-material amendment under section 96A may be available, and whether a change of brick is non-material is a judgement for the authority that turns on how visible the elevation is.
Do not substitute and then seek approval. A wall built in the wrong brick is a breach of condition, the remedy is expensive, and the authority's willingness to approve a substitution drops sharply once it is already built. Where the substitution affects the appearance of a scheme that attracted objections, expect the authority to reconsult, for the reasons set out in the article on re-consultation after amended plans.
When the council refuses to approve a material
A refusal to approve details required by a condition carries a right of appeal under section 78 of the 1990 Act, in the same way as a refusal of planning permission. That surprises people.
Before appealing, work out what the objection is. Officers refuse materials submissions for three reasons: the sample does not match what the permission described, the submission is incomplete, or the officer takes a different view of appearance from the applicant. The first two are fixed by resubmission. Only the third is worth an appeal, and appeals on materials are slow relative to the cost of a second panel.
The pragmatic route is a meeting on site with the panel in front of both parties. Officers will usually say what they would accept, and a middle option, a different mortar with the same brick, resolves most of these.
Keep the refusal letter. Where an authority refuses a material it previously indicated it would accept, the correspondence matters, and it will matter more if the disagreement reaches an appeal.
Getting the wording right before the decision issues
The most useful work happens before the decision notice is issued, and most applicants never ask.
Ask the case officer for the draft conditions. Most will share them, and at that point you can:
- Ask for materials already specified on drawings to be approved by reference to those drawings rather than conditioned again.
- Ask for the trigger to be the relevant part of the works rather than the start of development, so submissions can be phased.
- Ask for the list of elements requiring approval to be specific rather than "all external materials".
- Ask whether a panel is required, and for which elements, so it can be programmed.
- Confirm your written agreement to any condition that must be discharged before work begins where it is necessary, or object to it with reasons.
Specify materials properly in the submission and there is less to condition. A Design and Access Statement that names the brick, the mortar, the bond and the window finish, with a materials board referenced in the drawings, often reduces a materials condition to a confirmation exercise. That is an hour of work at application stage against several weeks on site.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
How long does it take to discharge a materials condition?
The authority has up to eight weeks to determine the request, and a site visit to inspect a sample panel has to fit inside that. Add time for procurement lead times and for any revised panel the officer asks for. Nothing prevents submitting the discharge application as soon as the permission is issued.
What does a sample panel have to show?
Normally around one square metre built on site in the proposed brick or stone, with the proposed mortar mix, joint profile and bond, positioned where it can be seen in daylight against the existing building. Panels usually fail on mortar colour or joint profile rather than on the brick itself.
Can a council require approval before any work begins?
Only with the applicant's written agreement. Section 100ZA of the Town and Country Planning Act 1990 and the regulations made under it require agreement to conditions that must be discharged before development begins. Most authorities now tie materials conditions to above ground works, or to the relevant part of the works, which is more workable.
What if the approved brick becomes unavailable?
Where it was approved under the condition, submit a further request under the same condition with a comparison and, if the difference is visible, a new panel. Where the product is named in the condition wording, a section 73 application is needed. Never substitute first and seek approval afterwards.
Can I appeal a refusal to approve materials?
Yes. A refusal to approve details required by a condition carries a right of appeal under section 78, the same as a refusal of permission. Before appealing, establish whether the objection is a mismatch, an incomplete submission or a genuine difference of view, because only the last is worth appealing.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.