What Are the Best Skylights for a Pitched Roof?

A pitched roof already has a slope that glass can sit within. A roof window is made for that. It is framed to be fitted between the rafters, flashed to the tiles or slates around it, and sized to take the angle of the roof. It gives daylight from above, can open for air, and keeps its profile low so it does not stand proud of the roof.

VELUX is the name most people know, and its codes are easy to read once you know the pattern. Take MK04. The M and K carry the width and 04 the height, so the letters and digits each tell part of the size. Other makers offer comparable units, and a good fitter will help you choose by the opening and the spot below, not by the brand. Our page on roof windows goes through the range.

Start with the place the daylight has to reach. A roof window above a bed, a desk or the top of a staircase lights that place. The slope of the roof decides the angle at which the daylight falls and how high up the opening sits.

• A steep pitch tilts the glass towards the sky and lights deeper into the room.
• A shallow pitch gives a smaller window height for the same opening, so the unit sits nearer the ceiling and the light is more even.
• A loft room with low eaves is lit best by a window positioned over the usable floor, not over the low edge.

The handle and the opening matter too. A top-hung window opens outward from the top, which suits most positions. In a higher spot a roof window that is hard to reach can be fitted with an electric opening, which we cover under electric opening rooflights.

A few pitched roofs call for a different unit.

• A conservation or heritage roof benefits from a conservation rooflight, a slim steel-look unit that sits flush with the slates. See conservation rooflights.
• A small, windowless space such as a landing, hallway or cupboard can be lit by a sun tunnel, a tube that carries daylight down from the roof. See sun tunnels.
• A pitched roof over an extension may suit a lantern if the roof is flat at the top, or the room wants a larger feature of glass.

Which one is right depends on the spot, the room and the roof covering, and we look at all three at the survey. Slate, plain tile and large-format tile roofs each need their own flashing kit, and the covering is checked before a unit is ordered so that the flashing matches it.

On a pitched roof the glass faces the weather directly, so the build-up matters. Look for a low-emissivity coating, a gas fill, and a warm edge. A south facing slope may need solar control glass to stop the room overheating, and a north facing slope will want the warmest build to keep the heat in. Our guide to double or triple glazed rooflights goes further.

A roof window is judged against the window standard for heat loss. Cutting a fresh opening alters the roof structure, so approval comes through the local authority or a registered building control approver, and our team makes the notification where one is due. Escape is a separate matter under Approved Document B. Height governs it, and the figure is 4.5 m. Beyond that, a roof window is not accepted as the exit, so on a two-storey house a loft bedroom is served by a protected stair instead. A bungalow or chalet bungalow keeps the option for rooms in its roof, within that height.

Houses often have permitted development rights for rooflights, with conditions attached. Our planning guide covers them, so read it before planning the work.

The best skylight for your pitched roof is the one that lights the spot you care about. The free survey takes in the room first, then the spot you care about, then the roof, and a price comes after all three. We recommend a unit and a position for it. The fixed written quote stays as written. For a lone straightforward rooflight the time up on the roof is usually one or two days, and a 10-year workmanship guarantee in writing goes with the job.

Start with the survey form, or WhatsApp 07880 284133 with a photo of the roof. For the wider picture see energy efficient rooflights.