Do You Need Planning Permission for a Velux in Taunton?

Class C of Part 1, Schedule 2 of the General Permitted Development Order 2015 is the catch-all for changes to the roof of a house. Re-roofing sits inside it, and so does a roof window set into the existing roof plane, as long as the limits below are met. Changing the covering on a house is ordinarily allowed without an application.

Does a roof window count as development at all?

Planning law does not count a job as development when how the building looks from outside is materially unchanged. A new window in a slope does alter the look of the roof, so the usual route is to rely on Class C. A like-for-like swap of an old unit for a similar one carries the lowest risk of all, since the roof outline stays the same. Putting a new unit into a slope that has never had one is the case that deserves a second look at the limits.

Class C speaks of a dwellinghouse, and the Order is explicit that the term leaves out a building containing flats, and a flat inside such a building. That matters in the later section on flats, and it matters for business premises, where our post on roof windows for offices, shops and workshops explains why you ask before assuming.

Always check with Somerset Council's planning team for your own address. They can tell you whether any condition from an earlier permission, such as one attached to a new-build estate, takes away rights that a plain house would have. Estates built in the last few decades are the likeliest places for that to happen, so it is worth the phone call.

Class C is switched off in certain cases. The first is in paragraph C.1(b): the right stops applying where the new work would project beyond the original slope by more than 0.15 metres, taken at right angles to the roof surface.

Why does that matter for a window?

A unit must not rise more than 0.15 metres, roughly the length of a hand, above the line of the slope. The measurement runs perpendicular to the roof surface, not up from the ground. How far a unit stands above the covering depends on the model and on the depth of the tiles or slates around it, so the model's own data sheet is the place to read the height. Ask us to confirm it against your covering during the survey.

What if the window sits too proud?

Then the permitted development cover is lost and a householder application becomes the route. A lower-profile model is often the simpler fix. A unit that breaches the limit is not illegal by simply existing, but it lacks the cover that would have made an application unnecessary, so it is better to find out before the order goes in.

Our guide to fitting a new roof window explains how rafters, trimming and the Building Regulations sit alongside the planning limit, and why a larger opening needs more than a quick cut through the covering. If the opening needs a new header or trimmer, the structural side is a Building Regulations matter even where planning is not needed.

The second Class C point is a condition rather than a limit. On a slope that faces sideways, any roof window has to carry obscured glass. It must also stay closed unless the opening part sits more than 1.7 metres above the floor inside.

Does every side-facing window need obscure glass?

Yes. Obscure glazing applies in every case. The 1.7 metre figure eases only the second part, the rule on opening. A window whose opening part sits higher than 1.7 metres up may open, and a lower one has to stay fixed shut. A common slip is to read the 1.7 metres as easing both requirements, which it does not.

What counts as a side elevation?

It is the slope that forms a side of the house rather than its front or back. On a terrace whose pitched roof runs front to back, the slopes face the street and the garden, so the condition rarely bites. On a gable-fronted house, or a hipped roof with a slope facing a neighbour, it does. If you are unsure which slope your house presents, the planning team can confirm it, and our answer on side-facing roof windows and obscure glass goes through the cases.

The point of the condition is the neighbour next door: a clear, openable window looking sideways from a loft room could overlook their garden or windows. Obscure glass lets light in without the view, and a high opening part lets air in without giving one either. Note that a window can be fixed shut and still be the right choice for a sideways slope, since a bright loft room does not need a view of the neighbours to feel pleasant.

Taunton has a long list of conservation areas. On Somerset Council's table, Staplegrove Road and South Road were designated on 15 January 1975, as were several others, and 14 March 2023 is the date given for Haines Hill and Trull Road. Mount Street and Vivary Park is designated too, though the table gives no date we can rely on.

Does a conservation area stop a roof window?

Not by itself. The Order groups conservation areas, National Parks and AONBs together as article 2(3) land, and some rights are lost there, such as permitted development dormers. Class C carries no article 2(3) exclusion. Inside a conservation area, then, a roof window that keeps to the limits remains permitted development, unless an Article 4 direction, or a condition attached to the planning permission, takes that right away. A dormer, by contrast, is a box built out of the slope, and it is not permitted development in a conservation area.

What is an Article 4 direction?

It is an order made by the local planning authority that removes chosen permitted development rights from a defined area, so that an application is needed for work that would otherwise be allowed. Somerset Council's list includes Staplegrove Road in Taunton (confirmed 1977). The planning team holds the direction documents, so ask them what a particular direction removes. Our pages on roof work in Taunton's conservation areas and conservation roof windows explain the practical side.

A listed house keeps Class B and Class C permitted development, since the Order excludes listed houses from neither class. Listed building law is separate, though: section 7 of the 1990 Act bars alterations that change what gives a listed building its architectural or historic interest, unless they are authorised. A roof window on a listed home therefore needs listed building consent through the council as well, however small the unit. A conservation-style window with a slim frame and a low profile can help an application, because it respects the roof line.

What about work to a listed building's neighbours?

Putting a roof window in a house next to a listed building does not need listed building consent, but the planning team may still care about how it looks if the property is also in a conservation area. Email the planning team ahead of the work and file the reply with your house papers, where a later conveyancing enquiry can find it.

What about Exmoor and the National Landscapes?

Inside Exmoor National Park, Exmoor National Park Authority handles planning itself, so those questions are for it to answer, not Somerset Council. In the Quantock Hills, Blackdown Hills and Mendip Hills National Landscapes, the former AONBs, dormers cannot be built under permitted development. The designation itself does not remove the roof window right. Check with the right authority for your address, because a house can sit just inside or just outside a boundary and the answer changes with it. Villages along the Quantocks and the Blackdowns are the places where that question most often needs asking, and the Park or National Landscape boundary maps are the quickest way to see where a house falls.

Planning is one half of the picture. A flat has no householder permitted development, since the Order's wording for a house leaves flats out. A roof window in a flat, or in a house converted into flats, needs the planning team's view first, and your lease is worth reading too. A shop, office or workshop also sits outside the householder rules.

Is Building Regulations approval a separate matter?

Yes. Planning permission and Building Regulations are different regimes. A roof window must meet energy figures, structural requirements around the opening and, on some jobs, fire and escape rules. The 1.4 or WER Band B figure applies to roof windows in homes, as our post on replacing old roof windows for energy efficiency explains. Somerset Building Control can be reached on 0300 303 7790.

What should you gather first?

Find out the type of property, whether it is listed or in a conservation area, whether an Article 4 direction is listed for the place, and which slope the window will face. Photograph the roof, note the covering and measure the proposed opening, including the distance from the ridge and the eaves. Then contact the planning team with those facts, and ask what they would like to see in writing. If you are not sure about any of them, tell us at the survey, because listed and conservation homes need the right consent route before the first slate is lifted. Our roof window and skylight installation page explains the work itself.