When you're planning a loft conversion, an extension, or any other building work to your property, knowing what paperwork you need to sort can be difficult. From working out whether you need planning permission for your loft conversion, to deciding which roof windows to choose, there's a lot to consider.
Every step of the way, you'll need to make sure you are following planning law and abiding by any relevant building regulations, and that includes when you're installing a simple conversion with roof windows. While most types of roof window don't need planning permission, it's always best to check before your project begins. You could be forced to undo your work — or even pay a fine.
In this article, we're going to explain everything, from your permitted development rights and planning permission, to building regulations and approval from your local authority. We'll cover:
Many roof windows don't always require planning permission. In fact, most straightforward fittings don't, including pitched roof windows and skylights, or flat roof windows. The installation of roof windows requires only small structural changes to your property, so as long as your roof windows fit the criteria for permitted development, you won't need to apply for planning permission. You will, however, still need to seek building regulations approval.
Permitted development rules outline what alterations you can make to your property without seeking planning permission. You can install or replace roof windows under permitted development subject to the following conditions:
Your roof window installer will be able to help you draw up a plan for roof windows in line with permitted development rules, plus work out whether your roof is suitable for a roof window. For example, if your roof is high enough for a loft conversion but is lower than you'd like it to be, you might want to consider a dormer window or extension instead.
You will always need planning permission for skylights or roof windows if you’re a leaseholder or you live in a building where your local authority has made an Article 4 Direction, removing your permitted development rights.
This is normally done in protected and conservation zones where the character of the area could be negatively impacted. If you are unsure whether this affects you, please contact your local planning authority. If you do have to seek planning permission for windows, you can do this online.
It’s worth noting that, if you live in a conservation area, there are certain kinds of roof windows that are more likely to be accepted by your planning authority due to their decreased visual impact. These are known as conservation windows and are designed to look more traditional and in-keeping with both slate and tiled roofs, making them less likely to affect the character of an area.
Whether you need planning permission to install your new roof windows or not, you must still follow any relevant building regulations outlined in the Planning Portal, and seek building regulations approval for any work you have carried out.
By law, all modifications to buildings must comply with these regulations, which highlight the minimum legal standards for design and safety. Of particular importance with regards to roof windows are section J and section L of the building regulations, which deal with energy efficiency, thermal insulation, and protection against fire.
Adding new or altering existing roof windows can undermine the integrity of the building, so special care must be taken to ensure that the roof continues to perform as it should and meet all building regulations requirements. This is because:
Please note: If the work is being carried out by a professional tradesperson who is registered with a competent person scheme, they can self-certify that any works meet the building regulation standards themselves. If you would like your roof windows to be installed without any hassle, we recommend hiring a professional team with years of experience to carry out the work for you.
Verandas and balconies are not considered permitted development and will always require planning permission. This is because they need a lot of support to make sure they're safe, so they can take a long time to complete and may require a large amount of structural rebuilding. However, balconies add a lot of extra floorspace to a loft conversion and can even improve the value of the property, so they're a very tempting addition to make.
Fortunately, Juliet balconies and balcony windows do not require planning permission. This is because no additional floorspace is added, just a railing and (in the case of windows) an upper and lower sash. So, they are classed as permitted development as long as they follow the same rules as roof windows. For this reason, balcony windows are a great way to enjoy a balcony without the hassle of acquiring or paying for planning permission.
Dormer windows, sometimes called 'doghouse windows' because of their shape and structure, require more planning and construction than roof windows and often have a slightly higher cost, as well as total project length. But, most dormer windows are classed as permitted development, under the same conditions as roof windows. So, you only need building regulation approval and not planning permission for a dormer window.
If you're looking to drastically improve the headspace or the volume of your loft, a dormer loft conversion may be more appropriate for your property than dormer windows. Often, these don't require planning permission either. Read our guide to planning permission for loft conversions for more information about dormer conversions.
Roof lanterns are slightly different to skylights and pitched roof windows because they are much larger and take up more of the roof. That makes them great for allowing the most light into your loft conversion or extension, and they're a very appealing option for opening up small spaces. But as so much work needs to be done to install them, you might be wondering whether you need planning permission for a roof lantern.
The good news is that most roof lanterns are permitted development and don't require planning permission — just building regulations approval. Of course, this depends on whether your property is in a conservation area or not, and the roof lantern must not exceed the height of your existing roof. In these instances, you should seek planning permission.
This guide can help you work out whether you need planning permission for your windows, whether they are balcony, dormer, skylight, or roof lantern. Remember to always consult a professional for guidance to make sure your project follows the rules of permitted development (if you don't seek planning permission), and your works are sure to go ahead without a hitch.
Here at RW4Y, we specialise in providing roof windows, flashings, and blinds to everyone, from tradespeople to DIYers. With a huge range of styles to suit your home or property and a great selection of features with bespoke options available, we're sure to have what you need to create your dream loft conversion, extension, or renovation.
If you're installing roof windows as part of a project, take a look at the guides in our knowledge hub. We have plenty more useful advice plus loft design tips for you to check out too. Why not follow us on Instagram for daily design ideas and beautiful conversion stories? We’d love to see how you convert your space into a charming addition to your home!
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