New dormer window installation and leaking dormer repair across Stratford-upon-Avon and Warwickshire. Correct waterproofing, conservation area guidance and planning advice. Free surveys and quotes.
Dormer windows create three separate waterproofing challenges simultaneously: the flat or pitched roof over the dormer structure, the cheek flashings on the vertical sides, and the apron flashing at the base where the dormer meets the main roof slope. All three interfaces must be correctly specified and executed for the dormer to remain watertight over its design life. A poorly waterproofed dormer is one of the most persistently problematic roofing situations we encounter — intermittent leaks that are hard to locate and easy to incorrectly repair.
We install new dormer window structures and carry out targeted waterproofing repairs on existing dormers across Stratford and Warwickshire. For new dormers on conservation area properties in Stratford's Old Town, we advise on planning requirements before any structural work begins — a dormer added without the appropriate consent can require costly removal. For leaking existing dormers, we assess all three potential failure points systematically before proposing any remedial work.
A new dormer installation begins with assessment of the structural rafter arrangement in the existing roof, planning status confirmation, and specification of the dormer size and roof covering. For rear dormers on standard Stratford semis outside conservation areas, this is typically a straightforward permitted development project. For conservation area properties or larger loft conversion dormers, planning and structural engineer input is required before the roofing work begins.
The most common dormer repair we carry out in Stratford is lead cheek flashing failure on older dormers. The lead flashing on the vertical cheeks of a dormer must be dressed over the tile or slate surface below and wedged into the timber cheek cladding above. Original lead on dormers built in the 1960s and 1970s is now typically at or past end of life. We re-dress with code 4 lead to correct lap dimensions and wedge into a proper chase rather than surface sealing, which is the correct long-term repair.
Free quotes — no call-out fees — honest advice.
“Rear dormer had been leaking intermittently for three years — two previous roofers had patched it without diagnosing correctly. These lads found the cheek flashing failure immediately, re-dressed in lead correctly and the leak has completely stopped.”
“New small box dormer for a loft conversion. They confirmed permitted development status, specified lead flat roof and tile cheeks matching the main roof. Watertight and visually correct. Good outcome.”
“Dormer flat roof on a 1970s property had failed felt. GRP replacement in one day. They also re-dressed the apron flashing at the same visit which was the actual leak source. Very thorough diagnosis.”
Most rear dormer window additions on residential properties in Stratford fall within permitted development rights if they meet specific dimensional limits: the dormer cannot exceed the height of the existing roof, cannot be on the principal elevation, and must be set back from the gable ends and the eaves. Properties in Stratford's conservation area, listed buildings, and certain Article 4 Direction areas require a planning application before any dormer can be added. We advise on planning status in every survey.
A single rear dormer window on a standard Stratford semi-detached typically costs £5,000 to £12,000 depending on size, specification and whether a full loft conversion is involved. A box dormer providing additional headroom for a loft conversion is at the higher end. A smaller "shed" dormer for a roof light alternative is at the lower end. We provide free surveys and fully itemised quotes for all dormer and roof alteration work.
Yes. Leaking dormers are one of the more common repair calls we receive in Stratford. Dormers have multiple waterproofing interfaces — cheek flashings on the vertical sides, an apron flashing at the base, and a ridge or flat roof above — any of which can fail independently. We assess the specific failure point and repair only what is failing, rather than defaulting to a full strip and rebuild. Free assessments available for all Stratford dormer repairs.
For dormers on Stratford properties within the conservation area, the dormer roof covering must typically match the main roof or use a sympathetically related material. On non-conservation properties, a small dormer flat roof is usually specified in lead (the traditional material) or GRP fibreglass for its seamless weatherproofing. Dormer cheek cladding is typically tile, slate or hanging tile to match the main roof. We advise on the appropriate specification for each property in the free survey.
A properly designed and constructed rear dormer that creates a usable loft bedroom with adequate headroom typically adds value to a Stratford property. The added value depends on the local market, the quality of the conversion and whether planning consent was properly obtained. We focus on the roofing and weatherproofing elements of dormer additions — structural and interior conversion work is outside our scope but we work alongside conversion specialists regularly.
No call-out fees. No obligation. Local roofers covering Stratford and Warwickshire since 2003.
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