Skylights and rooflights in Ash Green

Wikipedia puts it plainly. Ash Green is a village in the borough of Nuneaton and Bedworth, in Warwickshire, and it forms part of the Coventry and Bedworth urban area. In everyday terms it is an outer suburb of Coventry, and it shares the Coventry post town. The city boundary runs immediately south of the village, along the former colliery railway line beside Winding House Lane and Central Boulevard, and Ash Green is essentially contiguous with Coventry's Holbrooks district.

The postcode and the planning authority are different things. Your letters say Coventry, but your planning authority is Nuneaton and Bedworth Borough Council. It decides applications, keeps the list of local designations and answers questions about your address. We contact the borough, not the city, when we check a roof here.

For an ordinary house, rooflights are generally covered by permitted development, which means no planning application. The conditions in Class C of the 2015 order are three: the unit stands no more than 150mm off the slope, it never overtops the roof's highest part, and a side-facing window is frosted and fixed, bar the case of an opening light that is over 1.7m off the floor. The full planning guide lays out the detail. A direction under Article 4 can take the allowance away, so the borough hears from us before we quote.

Regulations follow the roof, whichever council it is. Cutting a new opening changes the structure, so we deal with Building Control when the job requires notifying, using the borough or a private registered approver, and we keep the record for you.

A word on the paperwork you may meet later. If you sell, a buyer's solicitor may ask what has been done to the roof and whether the opening was notified. We keep the notification and the guarantee together so that the answer is a single document, not a hunt through emails. The guarantee on our workmanship covers ten years.

Some villages come with a long written history, and some do not. For Ash Green there is no sourced account of when its streets went up or what they are made of. We have decided not to fill that gap with guesses about estates or builders. What we can describe is the way we survey a roof when nobody can tell us what is under the covering: slowly, from inside as well as out.

Start in the loft. Rafters, purlins or trussed members: each leaves different room for a frame. If the roof is built from trussed rafters, the timbers are set at regular centres and a window has to either fit between two of them or have a trimmer fitted. If it is a cut roof, with purlins and heavier rafters, the options are different, and sometimes wider. The survey tells us which one we have before the price is set.

Next, outside. The covering decides the flashing: tiles, slates and profiled sheets each take a different kit. We check the condition of the battens near the proposed opening, the line of the guttering below it, and the position of anything that gets in the way, such as a chimney, a satellite dish or a vent. A roof window should sit away from them.

Then the room. A roof window in a bedroom wants a different position from one in a bathroom or a landing. In a bathroom it clears steam and gives privacy if it is set high. On a landing it lights the stairs. In a bedroom it should not catch the pillow at dawn. These are practical points, and we raise them while we are standing in the space with you.

Extensions have their own rules of thumb. A flat roof rooflight works hard if the kerb is right. The upstand should be tall enough for water to leave the glass and sit on a roof that falls away, since a roof with no fall pools water around the frame. When the existing roof is dead flat, we build a small fall into the kerb or the surrounding roof so that it drains.

Where a room has no outside wall at all and a roof slope is awkward to reach, a sun tunnel may be the better answer. A rigid or flexible tube links a roof dome to a ceiling diffuser. It carries less light than a full rooflight, but it needs a very small hole and it works in places a window cannot go.

Size is where a VELUX window earns its code. Take MK04: the MK letters set the width and the 04 sets the height. If you have one already and want its twin, the label in the frame tells us which. For a new opening, we choose from the sizes that clear the rafters, which is why the loft visit comes before the order.

Cost follows from those choices, not the other way round. A simple swap on a pitched roof is a short job. A new opening in a trussed roof, a lined and boarded loft room and a flat kerb with a fall built in are all longer ones, and each is priced on what the survey found.

Last, the practical bit people forget: where the light goes once it comes in. A new window over a landing throws a patch across the stairs that moves with the sun, which is lovely until it falls on a television. We talk through where the patch will land at different times, and sometimes move the opening a rafter bay to put it somewhere kinder.

The village has clear edges. The M6 runs to the north and the A444, named Phoenix Way, runs to the east, with Winding House Lane and Central Boulevard to the south and Keresley End, also called Keresley Newlands, to the west. Water runs through it too: Breach Brook and the River Sowe are the main waterways in the area. Longford Community Nature Park is recorded about 2 km away.

Our travel is simple. Count 26.6 road miles from Leicester, heading south-west, and expect roughly 37 minutes at the wheel. Coventry Arena, an open station, stands 2 km off, and the closed Longford and Exhall station is 1.7 km off. Nearby places in the mapping data include Bedworth Heath, Rowley's Green and Keresley Newlands, each roughly 1.4 to 1.5 km from the village point.

Think about how the light behaves where you live. A village with a motorway to the north has open sky to the south, so a south-facing slope can be bright and hot in summer. Solar control glass cuts the heat without darkening the room, and we ask about the aspect before we suggest it. A north slope gives an even, cooler light that suits a workspace.

Glass has to be chosen for the slope it goes in. A pane facing south takes the sun for most of the day, and without solar control it can turn a bedroom into an oven in July. Coated glass reflects part of the heat while letting the light in, at a small cost in tint. A north-facing pane needs none of that, and a clear, well-insulated unit suits it better. We ask which way the roof faces before we talk about glass at all.

Fresh air deserves a thought too. Heat gathers at the highest point under a roof, and an opening window there lets it escape while cooler air drifts in below, much as a chimney draws. The same opening shifts steam from a bathroom. Where the glass would sit beyond arm's length, above a stairwell say, an electric opening rooflight runs from a wall switch or a remote, and the power feed is best planned before the plasterer arrives. Tell us early if you are building or re-lining the room anyway; it is the cheapest moment to run the cable.

A single rooflight is a modest job, and the standard of finish matters because the result sits directly over your head. We take care over the lining, the paint line and the dust, and we leave the room as we found it. The roof is sealed before we leave, and we do not go home until it is.