Get a Quote

The short version

Email info@severnskylightsgloucester.co.uk, or use the enquiry form on the contact page, with a photograph of the roof, a photograph of the room underneath, the address or at least the town, what the roof is covered with if you know, a rough size, and a note about access. That is enough to price a range against. Everything below is an explanation of why each item changes the answer.

Photographs, and the two that do most of the work

Two photographs answer more questions than a page of description.

The first is the roof slope from outside, taken from the garden, the street or an upstairs window of the house behind if that is where the view is. It wants to show the whole slope in one frame: ridge, eaves, verge, and any chimney, valley, hip or existing opening. From that comes the covering, roughly the pitch, the number of courses of run available, and whether the position somebody has in mind is anywhere near a feature that rules it out.

The second is the room from inside, taken from the doorway with the ceiling in shot. That gives the shape of the ceiling, whether there is a flat area or a full slope, where the existing daylight comes from, and how dark the far side of the room actually is.

Two more are worth adding where they exist. A photograph inside the loft or roof void, with a torch, showing rafters, purlins and any tank or pipework. And a close photograph of the covering itself from a metre or so away, which distinguishes a machine-made plain tile from a handmade one and a Welsh slate from a fibre cement imitation faster than any description.

Rough measurements are enough at this stage

Nobody expects survey accuracy from a homeowner with a tape and a stepladder. Approximate numbers move a range a long way, though, so send whatever is easy to get.

• The size of the room below, roughly, in metres.
• The run of the slope you are interested in, measured from gutter to ridge or from gutter to the wall it abuts. This one matters more than any other figure, because the flashing laps above and below a unit eat into it.
• The spacing between rafters if you can see them in the loft, usually 400mm, 450mm or 600mm.
• The size of unit you have in mind, if you already have one in mind. A VELUX size code stamped on an existing sash is even better.
• Ceiling height in the room, if the room is a loft or has a sloping ceiling.

The roof covering, in as much detail as you have

The covering is the single biggest swing in a Gloucestershire range. Cotswold stone slate in diminishing courses means the courses come back up the slope and are re-laid with matched reclaimed material, which is skilled and slow. Concrete interlocking tile on an estate roof is at the other end: the tiles unclip and a standard flashing kit does the rest. Between the two sit Welsh slate, clay plain tile, pantile, lead and single-ply flat roofing, each with its own flashing kit and its own way of going wrong.

If the answer is honestly “I do not know what it is”, say that and send the close photograph. Guessing wrong is worse than not guessing, and identifying a covering from a good photograph is straightforward.

What the room is used for, and which way it faces

The use of the room decides the specification more than people expect.

A kitchen or utility room generates a lot of moisture, so background ventilation and the geometry of the reveal come into it early. A bedroom, particularly a loft bedroom, may need the unit to satisfy the escape requirement, which means a clear openable area of at least 0.33 square metres, a minimum of 450mm in both directions, and the bottom of the opening between 800 and 1100mm above the floor. A fixed unit in that position does not satisfy it, and finding that out at inspection stage is expensive. A bathroom needs laminated glass overhead and a unit that copes with humidity. A home office or a sitting room usually turns on glare and overheating rather than on ventilation.

Say which way the relevant slope faces, even approximately. South and west facing overhead glass wants a solar control coating, and a room with an overhead unit and no coating on a west slope gets uncomfortable on a summer afternoon. North facing is the opposite problem, where the argument is for a larger unit and a splayed reveal to get more of what light there is into the room.

Access notes, and why they matter more here than elsewhere

Access swings a Gloucestershire job further than the size of the unit does, so a sentence or two about it makes the first range far more accurate.

Useful things to mention: how many storeys the elevation is, whether a vehicle can get within a few metres of it, whether the approach is a shared lane, a footpath or a flight of steps, whether there is a level area to stand a tower or found a scaffold, and whether a garden gate, a conservatory, a retaining wall or a neighbour’s boundary sits between the road and the wall. In the Stroud valleys, at Chalford and Rodborough, scaffold is sometimes hand carried a long way and a lantern’s glass may need a mechanical lift. That is normal work here and it is priced properly when it is known in advance.

If you are replacing an existing unit

A replacement needs a few extra lines. The approximate age of the unit, the manufacturer and size code if there is a label or a stamped sash, whether the frame is timber or plastic, and what has gone wrong: misting between the panes, water at the frame during rain, a mark in the plaster at the corners of the reveal, or a unit that no longer closes properly.

Say also whether the room below is finished. A like-for-like swap in a plastered loft room can usually be done from outside, leaving the lining and decoration alone, and knowing that in advance keeps the range realistic. It is also worth saying how many units of the same age are in the roof, because units glazed on the same day tend to fail within a few years of each other and one scaffold covering all of them is materially cheaper than two. The detail is on the replacement page.

Consents, and what to mention if any apply

Mention it if the house is listed, in a conservation area, a flat or maisonette rather than a house, or if you know an Article 4 direction applies to the street. Most rooflights in a house go in under permitted development, but a listed building needs consent for an alteration whether or not anybody can see it, flats have no permitted development rights for roof alterations at all, and conservation areas usually shape which unit is acceptable rather than whether one is.

Where consent is likely to be involved, the sensible order is pre-application advice with photographs before anybody orders a unit. That is slower at the start and much cheaper than a refusal once scaffold is up.

The indicative range, and what it is and is not

The range comes back by email, usually within a couple of days. It is a bracket rather than a figure, and it is honest about which end of the bracket the job is likely to sit at and what would push it either way. It assumes what the photographs suggest about the structure, and it says so where an assumption is carrying weight, for example that a trussed roof will take a unit between two trusses without a designed member.

It exists to save both sides a wasted afternoon. If the range is well away from what you had in mind, that is a useful thing to discover by email. If it is close, it is worth booking the survey. No figures are published anywhere on this site, and the reasons for that are set out on the costs page.

The survey, and what it converts the range into

The survey takes about forty minutes for a single roof window and longer for a lantern. Rafter centres and depths, pitch off a digital level, purlins, binders and services in the void, insulation depth, the covering identified precisely with its headlap and batten gauge, the condition of the underlay, and the real access to the elevation. Anything the photographs left open gets closed.

It also produces the findings that are worth having in writing before work starts: an existing opening with no trimmer under it, a deck that ponds against the position you wanted, a purlin exactly where the head of the unit would land. Each of those changes the job, and each of them is better known before a price is fixed than after.

The fixed price, and what it itemises

After the survey the price is fixed and written down, and it separates the unit, the labour, the scaffold or access equipment, the Building Control notification and fee, and any structural design where one is needed. Where a conservation requirement adds reclaimed slate or a pre-application, that is its own line too.

It holds unless the scope changes at your request, or unless something structural is uncovered that was documented as a risk in the survey notes beforehand. Anything that arrives as a surprise on the day is a surprise for the wrong party, which is the whole reason for surveying properly before quoting.

What happens after you accept

The unit is ordered, the Building Control notification is submitted, and a date is set around the lead time for the unit and the availability of access equipment. Made-to-size flat roof rooflights and lanterns take longer to arrive than a stock roof window, and that lead time is stated with the price rather than discovered afterwards.

On the day, floors and furniture are covered before anything is cut, the covering is stripped back and stacked for re-use, and the opening is formed, filled and made watertight the same day. The roof is never left open overnight. The completion certificate follows in your name once the work is signed off, and the ten-year workmanship guarantee runs from the day the job is finished.