Skylights and rooflights for brick terraces in Stanley and the rooms they leave short of light

Finding the right slope and the right rafters

A roof window needs a clear run of rafters between its two sides. From the loft hatch we look at how far apart the rafters are and whether a chimney breast, a purlin or a party wall sits where the unit would go. Each house in a terrace is only one house wide, so the opening is placed within the width of the landing it serves.

What happens on the roof

Around the opening the tiles or slates come off by hand and are kept to go back on later. Between the rafters the opening is framed with trimmers, so the load any cut rafter carried is taken round the new frame. Because the cut changes the roof structure, the size of the opening is fixed first and the unit is ordered to suit it.

A short light well above the ceiling

A landing has a flat ceiling with loft space above it, so the roof window cannot sit directly over the plaster. A light well, a lined shaft between the frame and the ceiling, carries the daylight down to the landing. Its sides are insulated and finished white so that the shaft reflects light into the room.

Permission for a house roof

Wakefield Council can confirm what a particular street allows, and the conditions that apply to a house roof are set out on our skylight planning and Building Regulations page.

Swapping a worn roof window for a new one

A Stanley roof may already carry a roof window from an earlier loft conversion. A like-for-like replacement is sized to the existing opening where the frame allows, so the rafters stay as they are and the work stays on the roof and in the reveal. The new frame is flashed afresh into the covering, because an old flashing is not reused on a new unit.

Opening or fixed

Over a landing, an opening roof window lets stale air out of the stairwell on a warm day. A top-hung model gives clear headroom at the opening, and a centre-pivot model turns about its middle. On a landing, where no furniture sits beneath, either works, so the choice follows the slope and the budget of the roof.

A flat rooflight or a lantern

A flat rooflight sits low on its kerb and barely rises above the roof. A roof lantern is a miniature glazed roof with pitched sides, standing on an upstand above the flat roof. Aluminium gives slimmer and stronger bars, while uPVC is the cheaper material. Which one suits an extension depends on the ceiling height inside and on how much of the room needs the glass.

What the roof is covered with

A flat roof wears one of three coverings, felt, EPDM or GRP, and each needs a different upstand and weathering detail, so we identify the covering before anything is cut. A rooflight added to an existing flat roof is dressed into the covering. Makers do not agree on whether a stated size runs to the inside face of the kerb or to the outside face, and the opening is measured with that in mind.

Lanterns and the 150mm limit

A lantern stands well clear of the 150mm limit for permitted development in the usual case, so the council's answer, or the extension's own planning permission, settles it, as the guide to skylight planning explains.

Glass that meets today's limit

Under Part L a new rooflight, a lantern included, needs a U-value of 2.2 W/m²K. A unit reaches that figure through glazing in two or three panes, warm-edge spacers and low-emissivity coatings, and each step down in U-value keeps more of the kitchen's warmth inside.

Where the glass sits over the room

The rooflight goes over the stretch of floor that is short of daylight, often the strip beside the old wall instead of the middle of the roof. Joists run one way across an extension, and the opening is set between two of them where possible. That keeps the structural work small and leaves the ceiling line tidy.

Finishing the ceiling

Indoors, the opening is lined and its sides plastered, which leaves the ceiling round the glass ready for paint. A lantern can show the roof timbers around its base, and a plastered kerb lining keeps that edge clean.

How the tube gets from the slope to the ceiling

A sun tunnel has three parts: a dome on the roof slope, a mirrored tube through the void, and a diffuser set in the landing ceiling. Over a given run a rigid tube delivers more daylight than a flexible one, so a straight line from dome to diffuser is worth planning. On a tiled slope the dome is set in a flashing cut to the tile profile.

Loft boards and insulation near the tube

Loft boards are lifted where the tube comes down, and the insulation is replaced round it once it is in. A tube of this size normally fits in the gap between two rafters. Should a rafter or joist need cutting, that is structural work, and the notification it calls for is part of the same job.

The dome on the roof

The dome is a clear or frosted cap on a short upstand, and it sits on whichever slope has the clearest line down to the landing. It is a small unit, so it adds little to the roofline, and from the pavement it reads as a modest rise in the tiles.

Choosing the spot on the ceiling

The diffuser looks best at the top of the stairs, where light spills down the flight as well as across the landing. If the stair turns, the diffuser can go over the turn. We check on site that the tube's route from the roof is clear of wiring and water tanks.

When a roof window suits better

A tube serves a small landing well. Where the landing is long or the loft room above is used as a bedroom, a roof window may suit the house better, and both options are laid out on the sun tunnel installation page for comparison.