Velux & Roof Window Installation in Derby

Most pitched roofs take a roof window, but the covering decides the flashing kit and, on some older slate roofs around Normanton, whether the rafter spacing needs trimming to take a standard frame width. A century-old slate terrace and a 1960s tiled semi at Littleover are fitted differently even though both end up with the same type of window. The free survey confirms the roof's pitch, covering and rafter layout before any price is fixed, so there are no surprises once the covering is opened up.

Not necessarily. A grey haze or trapped condensation between the panes means the sealed double-glazed unit has failed, not usually the frame or the surrounding flashing, so where the frame and flashing are still sound we replace just the glazed unit. Where the frame has swollen, rotted, or the opening mechanism has seized as well, a full window replacement is the more sensible option. We check both at survey and quote for whichever your window actually needs.

A single re-glaze of an existing window is typically a half-day job. Cutting a genuinely new opening into a pitched roof — trimming rafters if needed, fitting the frame, and dressing a full flashing kit into the surrounding slate or tile — usually runs one to two days per window depending on the covering and access, and we give a realistic timescale in the written quote. Fitting several windows into one loft conversion at once takes longer and is scheduled as a single continuous job to limit the roof being open.

A straightforward like-for-like replacement generally does not trigger a fresh application, but a new roof window, particularly as part of a wider loft conversion, has to meet Building Regulations Part L for thermal performance and Part B for fire safety where it sits near an escape route or a boundary. A full loft conversion is very likely to need its own Building Regulations approval covering more than just the windows. We flag at survey whether your particular job falls into that category so you are not caught out later.

A sun tunnel, also called a light tube, channels daylight down through a small dome fitted on the roof and a reflective tube into a ceiling diffuser, and it suits a windowless landing, hallway or bathroom where there is no direct roof access above the room or where a full window would be disproportionate. It brings genuine natural light without cutting a large structural opening or disturbing much of the surrounding covering. We assess the loft space and roof pitch at survey to confirm a tunnel run is practical for your particular layout.

It can, if the reveal and surrounding insulation are not built correctly, because a cold-bridged frame or a gap in the insulation around the opening is exactly where warm, moist air condenses and black mould appears. We build every installation to BS 5250 condensation guidance, keeping insulation continuous around the window liner rather than leaving a thermal weak point. A window fitted this way should perform no differently to the roof around it.

Yes — a flat-roof extension behind a tiled semi at Mickleover or Allestree typically takes a flat rooflight or a glazed lantern set into the EPDM, GRP or felt covering itself, which is a different detail to a pitched Velux and sits alongside the flat roof's own falls and upstands. See flat roof repair and replacement for how the surrounding covering is specified. We fit both types and advise which suits your particular extension at survey.

That depends on the roof's size, pitch and the rafter spacing rather than a fixed number, and a loft conversion often takes two or three windows to light the whole space evenly rather than one oversized opening. Access, scaffolding and how many openings can be cut without weakening the rafter structure all feed into the survey. We set out a proposed layout and a fixed quote covering every window as part of the same job.

Where the existing flashing kit has hardened, cracked or corroded, yes — reusing tired flashing around a new window frame is a common cause of a 'new window' leaking within a year or two. We inspect the flashing at survey and include renewal in the written quote whenever it is due, rather than assuming the old kit will do for another decade. A new flashing kit matched to the covering is what actually keeps the roof weathertight, not the window glazing itself.

It should be, provided the flashing kit is correctly matched to the covering and dressed in proper courses under the surrounding slates or tiles rather than simply sealed over the top with mastic. We do not consider a roof window job finished until the surrounding covering is fully reinstated and checked, and every installation is covered by the same fixed written quote agreed at survey. Ring 07700 149979 if an existing roof window is letting water in and we will assess whether it is the flashing, the glazing or the frame.