Fitting a pair of roof windows next to each other is a popular way to flood a loft room with extra light, and it is entirely achievable with the right flashing and a bit of structural planning. It's a job seen fairly often in Bristol loft conversions where a single window just isn't enough to properly light the space.
How Twin Installations Work
Rather than fitting two separate windows with a gap between them, manufacturers produce combination flashing kits designed specifically to join windows together with a slim central mullion, giving a much cleaner, more deliberate look than two standalone units squeezed in close together and sealed separately.
The windows can be matched, for example two identical centre-pivot units, or mixed, such as a fixed window paired with an opening one, depending on how much ventilation the room needs and how the space will be used day to day.
Structural and Practical Considerations
Because a wider opening is being formed in the roof, the rafters either side need to be strong enough to carry the load, and in many cases a section will need trimming and additional timber added to support the combined structure properly. This is something a competent roofer checks before any tiles come off, not something to be decided on the day.
It's also worth factoring in that a larger combined opening may occasionally bring the work into planning considerations depending on its size and position, so it's worth asking Brunel Roofing Bristol to check this as part of the initial survey before any materials are ordered.
Cost and Timeframe for a Twin Install
As a very rough guide only, fitting two windows together with a combination flashing kit typically costs somewhat less than two entirely separate installations, since labour and some materials are shared, though the exact saving depends on window size and access. It usually adds a day or so to the job compared with a single window.
Actual cost and timing depend on your specific roof, so a free, no-obligation quote from Brunel Roofing Bristol is the best way to get figures you can plan around.
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