Big villa roofs often have the slope for a pair of roof windows. Whether it works depends on rafters, flashing and the shape of the room beneath.
Large Victorian and Edwardian villas in Sneyd Park often have generous roof slopes and deep loft rooms that welcome extra daylight. A pair of roof windows can make a real difference. Whether two fit side by side comes down to the structure, the covering and the layout, all of which we check from inside first.
The room beneath
We start inside the loft, looking at where the floor and ceiling meet the slope, what the room is for and where light is wanted. A pair sited well gives even daylight and a view. Sited badly, they leave dark corners. Standing height and sill height matter just as much as the width of the slope.
Rafters and the opening
Each opening interrupts at least one rafter. To keep the roof strong, rafters are trimmed and doubled up around each opening, and a pair needs the framing planned together. Old villa roofs may have heavy timbers and purlins in awkward places, which sometimes pushes the position a little to one side.
- Number of rafters cut by the two openings
- Position of purlins and other heavy timbers
- Gap needed between the windows
- Distance from ridge, hips and chimneys
Flashing for the covering
The windows must be fitted with a flashing kit made for the roof covering, whether slate or tile. For a pair, a linked kit joins the two and keeps the gap between them watertight. On a slate roof, the work around the openings needs particular care so the surrounding slates remain secure and the edges stay sound.
Whether the two windows sit tight together or with a strip of covering between them is decided by the rafters and the flashing kit, and we explain the reasons for the spacing rather than simply stating it, so you can picture the finished slope.
Lining and insulation
After framing and weathering, the inside is lined and insulated around each frame, with a vapour control layer so warm air does not condense on cold timber. Good finishing makes a pair look planned. Reveals are even, the plaster is tidy and the window heads line up across the slope.
Mature trees close to the house are worth noting, as they shade the slope and drop debris around the frames, so we think about how the windows will be cleaned and kept clear as well as how they will look.
Questions to ask
Ask whether the roof structure was inspected from the loft before the job was agreed, how the room below will be protected, and how the windows will be flashed into the covering. Roof windows may need planning or Building Regulations checks — we advise before work starts. Expect clear answers, not vague reassurance.
Frequently Asked Questions
Do two windows need more support than one?
Generally they need a little more framing, since two openings cut more of the roof. We plan the doubled-up rafters for both together, so the structure remains stiff and properly supported across the whole width of the pair.
Can slate roofs take a pair of roof windows?
Yes, with the correct flashing kit for slate and careful work around the openings. We look at the condition of the slates nearby first, because weak or brittle slates around a new opening cause trouble later on.
How far apart should the windows sit?
That depends on the rafters, the room and the flashing kit. Linked kits allow a close pairing, but the spacing is set from inside, so the framing, the light and the look all work together on the slope.
Talk to our team about VELUX and roof window installation in Sneyd Park
Every roof is different — the fastest way to get an accurate answer is a quick chat with our team.