For most houses, fitting a Velux or other roof window does not need planning permission, because it counts as permitted development. The exceptions catch people out, though: conservation areas, listed buildings, flats, and windows that stick out too far from the roof slope. This guide explains the rules as they apply to homes around Hythe, the New Forest and the wider South Coast, and what to sort out before anyone cuts a hole in your roof.
Roof windows on a house are covered by Class C of the General Permitted Development Order in England. If your project meets the conditions, you can go ahead without applying to the council. The conditions are fairly simple and apply whether you are fitting one window into a loft or four into a full conversion.
Be aware that permitted development rights belong to houses, not flats or maisonettes. If you live in a flat, even a top-floor one with direct access to the roof space, you will almost certainly need a planning application, and usually the freeholder's consent too.
The New Forest National Park Authority, rather than New Forest District Council, handles planning for a large part of the area around Hythe, Dibden, Marchwood and the villages west towards Lyndhurst. National Park status does not remove permitted development for roof windows on its own, but the Authority has placed Article 4 directions on some settlements and is stricter about anything visible from the road or open forest. It is worth a phone call or an email to check your address before you order windows.
Listed buildings are the other big one. Cutting into the roof of a listed cottage, and there are plenty across the Test Valley, Salisbury area and rural Dorset, needs listed building consent regardless of size. Doing it without consent is a criminal offence, not just a planning breach, so never rely on a builder telling you it will be fine.
Conservation areas in towns such as Lymington, Romsey, Wimborne and Salisbury often have Article 4 directions that specifically restrict roof alterations on street-facing slopes. A rear-facing Velux is usually still permitted; a front-facing one frequently is not.
Planning permission and building regulations are two separate things, and a lot of homeowners only think about the first. Even where no planning application is needed, fitting a roof window involves cutting roof timbers, which means the structural work must comply with building regulations. On a typical cut-rafter roof, a Velux wider than one rafter spacing needs trimmers and possibly doubled rafters either side.
The glazing also has to meet thermal performance requirements, currently a U-value of 1.4 W/m2K or better for replacement or new windows in an existing dwelling. Every current Velux model meets this, but older second-hand units you might pick up cheaply may not.
Most roofers handle this through a FENSA or CERTASS style competent person scheme for the glazing, or by notifying building control directly. A building notice for a single roof window in Hampshire or Dorset typically costs in the region of £150 to £300 depending on the council. Ask whoever does the work how they intend to certify it, and keep the paperwork, because solicitors will ask for it when you sell.
Start by searching your postcode on the relevant council or National Park planning portal. Look for any Article 4 direction, conservation area boundary or listing, and check the planning history of your own house for conditions that removed permitted development rights. Newer estates around Totton, Hythe and Dibden Purlieu quite often have this condition attached from the original consent.
If anything is unclear, a Lawful Development Certificate gives you written confirmation that the work is permitted. It costs half the fee of a full application, currently £129 for a householder certificate, and takes up to eight weeks. It is not compulsory, but it is worth having for a street-facing window or if you plan to sell in the next few years.
Finally, think about position and size at the same time as the legal side. A 780mm by 1180mm window (Velux size MK06) sits between rafters at 600mm centres with minimal structural work, which keeps costs down and stays well inside the 150mm projection rule. Larger or paired windows are perfectly doable but involve more cutting, so get the roofer to look at the loft before quoting.
No. Roof windows fall under Class C, which covers alterations to the roof, not Class B which covers additions such as dormers. That is why a flush-fitting Velux is usually permitted where a dormer in the same position would not be.
On a normal house outside a conservation area or Article 4 area, yes, provided it projects less than 150mm and does not rise above the ridge. In conservation areas across the New Forest, Salisbury and parts of Dorset, front-facing roof windows are often restricted, so check first.
The council can serve an enforcement notice requiring removal, though for minor breaches they often invite a retrospective application instead. For listed buildings the position is much more serious, so get consent before starting rather than hoping to regularise it afterwards.
Free quotes and free roof inspections across Hampshire, Wiltshire & Dorset.
Tell us about the job and we’ll come back with a free, no-obligation quote.