Tilda Publishing

Planning Permission

A question we are often asked is, "Do I require planning permission for a frameless glass extension?"
This depends on your local authority and their planning restrictions. If you know the approximate size that you are planning to build, you may be able to get a straightforward answer from their website or by making a quick call to them.
Frameless glass extensions are generally viewed very favourably by planning officers as they do not interrupt the original building too much and are unlikely to cause light blocking issues for neighbouring properties.

No-one wants to be held up by planning permission requirements, least of all us, but if plan-ning permission needs to be sought for your proposed glass extension it must be obtained first. You run a huge risk by ignoring these obligations as severe penalties can be imposed, such as your planning department ordering you to completely knock down the extension.

There is a possibility that you will neither need to spend any time or money on attempting to acquire planning permission if you have Permitted Development Rights.
Your glass extension must comply with the full set of rules below to be considered a Permit-ted Development and not require planning permission:

  • A handrail should be installed at both sides of a stair flight
  • For buildings with children ( 5 years of old and younger), staircase design regulations UK recommends excluding gaps in balustrades. The rule permits a gap of not less than 100mm
  • One of the staircase design building regulations for buildings with children, the second handrail has to be at 600mm above Finished Floor Level
  • Balustrade glass regulations UK state that a balustrade guarding shouldn't allow children from climbing it
  • The centerline of all handrails should be between 900mm and 975mm above the stair
  • For balustrades guarding landing areas and balconies, the barrier should be a minimum of 1100mm above Finished Floor Level
  • Glass balustrade standards state that handrails should extend a minimum of 300mm beyond the top and bottom riser of a flight
  • The handrail can be returned around a corner if needed
  • A permitted gap between the handrail and the wall should be between 50mm and 75mm
  • All handrails should be supported with fixings
  • A circular handrail should be of minimum 40 mm but not exceed 50 mm
  • Handrails have to be turned towards the floor to prevent catching and tearing clothes
* The term "original house" means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.

* Designated land includes conservation areas, national parks and the Broads, Areas of Out-standing Natural Beauty, and World Heritage Sites.

Unfortunately, we are unable to get involved with planning enquiries, this must be done by the property owner.
Listed Buildings

For many home or property owners, making any changes to a listed building can be a daunting task. The lists of regulations and restrictions in place are quite a lot of information to take in.

We've worked with many kinds of historical properties over the years. Our professionals are familiar with the design and construction of glass extensions for listed buildings. We've put this together to clear some of the points around the planning and application process in order to highlight the types of extensions that will most likely be accepted.

Why are buildings listed?

The term 'listed building' is fairly common in the British property market. If you're going to get your exten-sion approved it's really important to understand not only what this means, but also the reasons why cer-tain buildings are listed.

This might not seem immediately relevant, but if you understand the factors that are likely to lead to your designs getting approved, you stand a much better chance of receiving approval.

Listed buildings are recognised for their historical or architectural significance. This is broken down into different categories. These include Grade I, Grade II*, and Grade II.

Grade I

Grade I buildings are the finest. Only 2.5% of all listed properties fall into this category and are identified for their exceptional historical significance and interest. These would most likely be buildings such as churches, cathedrals, and castles.

Grade II*

Grade II* listed buildings are one tier down from Grade I. They're recognised for their significant place in history and their 'more than special' interest. Around 5.8% of listed buildings are Grade II*.

Grade II

Chances are, if you own or are working on a listed building, it falls into the category known as Grade II. The vast majority (91.7%, in fact) of listed buildings in the UK are Grade II, which indicates they are of special interest.

What does this mean for a home-owner?

If a building is of special interest, what implication does this have on the kind of renovation work the owner can undertake?

A building being listed does not mean it cannot be altered. It doesn't even necessarily mean it's going to be hard to change. All this signifies is that the character of the building is important, and that any altera-tions that you plan to make will need to take your home's unique aesthetic qualities and history into ac-count.

For example, if your property has centuries-old windows with charming wooden frames, you probably wouldn't be permitted to replace these with low-budget UPVC double glazing.

If, however, you apply to add a visually frameless glass extension at the rear of the home - one that won't have any negative impact on the character of the property itself - then you're much more likely to get your application approved.

What permissions do I need?

While improvements and renovations to all buildings in the UK are subject to Planning Permission, listed buildings require specific 'Listed Building Consent' from the local planning authority.

If you wish to make any changes to your property that will potentially impact upon its character, this is the permission you'll require. Importantly, you will have to obtain Planning Permission, Building Regulations approval and Listed Building Consent to extend your home. Making any changes without this consent is a criminal offence.

How do I get Listed Building Consent?

Before you hire any professionals it's important to speak to your local authority Conservation Officer.

Every building is different, and the factors that will influence whether your planned extension gets ap-proval or will differ greatly. Your local Conservation Officer can advise you as to the things that will influ-ence the approval of your application.

When it comes to putting together your proposal, it's important to do your homework. Research the his-tory of your building thoroughly, understand the things that contribute to its specific character, and take steps to show how you have factored this into your proposed changes.

It's also a good idea to hire an architect. They will be able to help you to design and draw up a proposal that not only serves the purpose you need but also conforms to the advice you've been given by your Con-servation Officer.

The listed building consent application process

Once you have received advice and put together an appropriate proposal, the application process itself is quite straightforward. If you have already made some pre-application enquiries (to avoid a rejection), you simply submit your proposal to your local authority.

They will then review your plans, and provided your project isn't of a very large scale, will aim to grant a decision within eight weeks, though major proposals can take up to thirteen weeks. This will include a stat-utory twenty one day consultation period for neighbours, local amenities providers, and any other relevant parties.

Provided you've followed the advice of your Conservation Officer, architect and glazing specialist, your ap-plication should be approved. If you're unsuccessful, however, you'll be given some written information as to why this is the case (although this is usually in government legalese, and you may need a professional to understand it). With a bit of luck, you can then use this to make some alterations to your plans before re-applying successfully.

If you believe the decision is unreasonable, you can also appeal to the Secretary of State for Communities and Local Government (DCLG) within six months of being turned down.

Glass Extensions for Listed Buildings

Why are glass extensions a preferable choice?

Glass extensions have become one of the most popular ways to extend a listed home, for several reasons.

One of the most important factors in getting approval for your proposed extension is the preservation of the original character of the building, which is one area in which glass extensions excel. The translucent property of glass means that a frameless structural glass extension does not obscure the original building, and instead maintains the architectural quality of the original construction.

Another thing that often arises with applications (particularly for much older buildings) is the need for a clear distinction between the old and new. While changes to the building itself often require the same ma-terials and designs as the original, an extension to a listed home is an entirely new structure. Local authori-ties usually insist that rather than try to make your extension 'blend in' like a chameleon, you take steps to make it stand out from the rest of your home.

The purpose isn't for the extension to detract from the aesthetic qualities of the building - quite the oppo-site - but instead to be subtly but clearly identifiable from the original structure. Essentially, the Conserva-tion Officer will want you to make it as obvious as possible which parts of the building are old, and which parts are new.

Glass extensions, particularly the frameless structural designs we build, serve this purpose to great effect. Their sleek modern design creates a strong visual contrast between the original building and the extension, but in way that's unobtrusive, and doesn't end up affecting the original qualities of the home.

What kind of glass extension should I choose?

Where possible, you should consult your architect and glazing specialist of choice, as the type of glass ex-tension you opt for will depend both on the building and the purpose it will serve. Through advances in modern structural glazing, glass extensions can be used for kitchens, glass offices, or to create the per-fect environment for general living and relaxing. A glass extension can make you feel like you are enjoy-ing your garden or outdoor space all year around while in the comfort of the indoors.

Glass links also make an attractive alternative for joining two buildings together while extending the usable indoor space, a particularly favourable option in the colder months or when it's wet outside.

View our previous projects on our website to get an overview of our previous work.

Types of glass.

When it comes to listed buildings, it's nearly always best to go for glazing that's as visually unobtrusive as possible. For this purpose, low iron glass is most often the best choice. This type of glazing contains less iron oxide, which is what gives glass a green tint.

It's also a good idea to opt for frameless glass solutions - the more glass (and less frame) on display, the more of the original building will be visible.

Consider the fact that even though your home is listed, the extension you're planning is very much a new build - and as such needs to comply to the Building Regulations. These are strict, but very clear, and one of the things they insist upon is energy efficiency. You should definitely consider double glazed units.

The design of the extension.

You need to consider how your extension will be constructed. You'll have to think about ventilation as well as energy efficiency and work out whether you need to include an access point or door leading outside.

If this is the case, then it's a good idea to opt for a door that's as slim and minimal as possible. Sliding solu-tions are almost always the best choice, and if it's possible then a frameless option - such as the frameless glass doors we offer.

Structurally, your architect/glazing specialist will be able to determine what will work best. It's possible to install glass beams, meaning that not only will your extension be frameless, it will be almost entirely clear which is likely to be looked upon favourably by a conservation officer.


While there is a lot to consider when it comes to extending a listed building, there are a few fundamental points. First and foremost, research as much as possible - get in touch with your local authority quickly to speak to them about your plans, find out what they would recommend, and do as much research as you can into the history of your building.

When it comes to putting together your proposal and drafting the designs for your glass extension, get in touch with the right professionals. Consulting an architect is nearly always the best choice -- and when it comes to designing the glazing, we are more than happy to be of assistance. (Feel free to email us on info@glassstructureslimited.com if you have any questions about glass extensions or other glass installa-tions, too!) www.gov.uk/planning-permission-england-wales/ is a useful link to the governments planning permission page