Narrow upstairs hallway with doors leading off and a landing beyond

Sun Tunnels in Derby

A narrow tube that carries daylight to a windowless corner.

Tell us which corner of the house stays dark. We survey the roof and the route, then fix the quote in writing.

Book a free survey

Free survey
Fixed written quote
10-year workmanship guarantee

Three dark corners a sun tunnel can reach

Hallway with a staircase at the far end lit by a round sun tunnel diffuser — The top of the stairs, where the landing has no window at all.

Long narrow corridor with wooden floorboards and plain white walls — An inner hallway that needs the lights on at noon.

Bathroom with a bath beneath a round sun tunnel diffuser — Over the bath, where a round diffuser brings daylight into the bathroom.

Ten years on our workmanship. In writing.

Surveyed before we price
A fixed written quote that does not change on the day
Building Control notification handled

How the guarantee works

Round sun tunnel diffuser set into a plastered ceiling

The full guide

Sun tunnels, from the landing up

A sun tunnel, sometimes called a sun pipe, is a small dome on the roof joined to a diffuser in the ceiling by a reflective tube. It suits rooms that a normal rooflight cannot reach. This guide explains how sun tunnels work, what shapes the result and how we fit them across Derby.

Dark landing
How bright
Dome and tube
Flashing joint
Roof build-up
Diffuser and finish

Callout 1

Sun tunnels in Derby, starting at the landing

From the first message to a lit landing

Send the survey form
Tell us which landing, hallway or bathroom stays dark and roughly where the loft sits above it.
We visit and look
We stand on the dark spot, climb into the loft and check the roof outside.
A fixed written quote
One figure arrives in writing and holds when we come to fit.
Dome and tube go in
The roof opening is cut, the flashing set, the tube run and the ceiling opening made.
Notification and handover
Building Control is told where the job needs it, then we show you the finished light.

Most people who ask about sun tunnels in Derby are not really asking about a product. They are asking about a stretch of floor. It might be the top of the stairs, where you carry washing in the half dark. It might be the hallway between the front door and the kitchen, or the bathroom where the basin sits against an inside wall. A sun tunnel is one of the few ways to put daylight in a place like that, because it does not need the room to touch the roof.

The idea is simple. A clear dome sits on the roof and gathers daylight. A tube with a mirror finish carries that light down through the loft. At the ceiling, a flat or domed diffuser spreads it into the room below. There is no frame in the roof the size of a window, no shaft to build and no need to move a rafter in most cases. That is why a sun tunnel is often the first idea for a space that looks impossible. If you would rather see the whole decision laid out, Are Sun Tunnels a Good Idea? gives the honest answer, including where they disappoint.

Sun tunnel, sun pipe, light tube

You will hear several names for the same thing. Sun tunnel and sun pipe are the common ones, and trade catalogues also say light tube or tubular rooflight. In the trade a sun tunnel counts as a small rooflight, and most homeowners call the dome a skylight. We use the words side by side in this guide because that is how people search. Whatever the name, the product is a dome, a tube and a diffuser, and the work is installation and replacement of those three parts as one system.

Why we begin with the spot

Our habit is to start on the floor itself. On a landing that means the top step, with the floor plan in hand. A sun tunnel puts its light almost straight below the diffuser, so the position of the ceiling opening matters more than the position of the dome. We mark the floor spot first, then work back up through the loft to find a route and a place on the roof. The roof side often has fewer choices than the ceiling side, which is why we survey both before any figure is written down.

Where a sun tunnel earns its keep

The best places are narrow, windowless and used every day. Sun Tunnels for Hallways, Landings and Bathrooms goes room by room. Landings and hallways are the obvious cases. Bathrooms and cloakrooms come next, since a diffuser lets in daylight without a view in. A utility room, a walk-in wardrobe or a boot room tucked inside the plan can all gain from the same idea.

The places where a sun tunnel struggles are rooms that are big, rooms far below the roof and rooms where you want a view of the sky. A living room that needs daylight over a whole sofa area, or a kitchen that needs a broad wash across the worktop, usually wants a roof window or a flat rooflight instead. Our other service pages, including roof windows and flat roof rooflights, explain those options.

What happens after you ask

Fill in the form below, or drop a line to the WhatsApp number. We come out, look at the dark spot, the loft above it and the roof outside. No price is given before that visit, since a figure from a photograph would be a guess. Afterwards the quote arrives in writing with one figure, and it stays put when we turn up. For a straightforward single tunnel, the roof is usually a one or two day job. The steps below show the order.

Homes first, small commercial jobs welcome

Most of our sun tunnel work is in houses, from terraces in the city to newer estates on the edge of it, and we cover Derby and about 30 road miles around it. Small commercial jobs are welcome too. A shop stock room, a corridor in a small office or a windowless toilet at a workshop all have the same problem as a house landing, and the same answer. The survey works the same way whether the building is a home or a unit.

A sun tunnel does not need the room to touch the roof, which is why it reaches the places a window cannot.

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How much light a sun tunnel really gives

People are right to be careful here. A sun tunnel is not a window and it is not a lamp. It carries a modest amount of daylight a long way, which is often exactly what a landing needs. The question of how bright it will be has several answers, and How Much Light Does a Sun Tunnel Give? works through them in detail. The short version follows.

What sets the brightness

Four things matter. The first is the diameter of the tube. A wider tube gathers more light at the dome and delivers more at the ceiling, but it also needs a bigger opening in the roof and a bigger path through the loft. The second is the length of the run. Every metre of tube loses a little light, because the mirror finish is good but not perfect. The third is the number of bends. A straight drop is brightest, and each elbow takes some away. The fourth is the roof itself, meaning its pitch, its direction and anything that shades the dome such as a chimney, a tree or a neighbouring gable.

A north-facing slope still works. Daylight reaches the dome from the whole sky, not just from the sun, so a sun tunnel will light a landing on a grey Derby morning, if more softly than on a bright one. We would rather say that plainly than promise a brilliant beam. At night the tunnel goes dark like any rooflight, unless you add a light kit that fits into the diffuser.

What changes the quote for a sun tunnel

Tube diameterA wider tube needs a larger roof opening and a bigger unit.
Length of the runA long drop through the loft needs more tube and more careful support.
Bends on the routeEach elbow adds parts and labour, and takes a little light.
Roof coveringSlate, plain tile and interlocking tile each need a different flashing.
Ceiling workA plastered ceiling needs a neat opening and a finish around the diffuser.
ExtrasA light kit or a vent fan adds parts and wiring to the job.

Judging it from the landing

The room below makes a difference too. A pale ceiling and pale walls pass the light along, so a small amount feels like a lot. A dark stairwell with deep-coloured walls swallows it. On the survey we look at the colour and the layout, then tell you whether one tunnel is enough or whether two smaller ones spread the light better along a long hall. Two tunnels often beat one big one in a long corridor, because the light lands in two places instead of one.

We also think about the spot you named. If the landing is a metre wide and the diffuser sits dead centre, the light falls where people walk. If the loft route forces the diffuser to the side, we can sometimes move it, and we say so when it will not work. Daylight is a result of the whole system, not of the dome alone.

Light and heat

People also ask whether a sun tunnel loses warmth or lets in too much heat. A tube is a small hole compared with a window, and a well-made unit has an insulated lid or a sealed second layer at the ceiling to cut the cold bridge. Our energy guidance on energy efficient rooflights explains how glazing is rated. For a sun tunnel the issue to watch is condensation on the inside of the dome during cold snaps, which we handle by choosing a sealed unit and checking the loft insulation around the tube.

None of this needs a calculation from you. It needs a visit, a tape measure and a look at the roof. That is the reason the survey is free and comes before any price.

Daylight arrives from the whole sky, so even a grey Derby morning puts light on the landing.

Callout 3

The dome, and the tube that follows it

A sun tunnel has three parts and each one can be done well or badly. The dome is where the light goes in, the tube is where it travels, and the diffuser is where it comes out. This chapter looks at the first two, because choices about them change the cost, the light and the fitting day.

The dome

The dome is usually moulded plastic, either acrylic or polycarbonate, and some makers add a flat glass option. A clear dome gathers the most light. A prismatic or textured dome scatters it, which can help when the sky is low. Some domes carry a second, inner layer, which cuts heat loss and slows condensation. Because the dome is the only part of the system outside, it has to take sun, frost and a decade of weather without clouding.

Older plastic domes can discolour, turn brittle or crack, and the seal can fail so the unit mists on the inside. If your existing sun tunnel is already in that state, we replace it. Our pages on misted rooflight replacement explain how we decide between a new dome and a whole new unit. We install and replace, we do not patch, so the quote will say which parts are coming out.

Rigid or flexible tube

The tube comes in two families. A rigid tube is made of straight aluminium sections with a very reflective inner surface. A flexible tube is a bendable duct, ridged like a vacuum hose, with a reflective liner. Both have a place. A rigid tube carries more light over a straight run, and a flexible tube lets us wriggle round a purlin, a water tank or a roof truss when a straight route is not there. Our page on rigid or flexible sun tunnels sets the trade-offs out at more length.

The honest rule is to use rigid where you can and flexible where you must. A short flexible section to dodge a joist on an otherwise straight run costs very little light. A long, curling flexible run loses a lot, and we would tell you to move the position instead. The compare box below sums up the differences.

The diffuser

At the ceiling the diffuser is the part you see. It can be a frosted flat panel or a shallow dome, in white or in a plain finish to suit a modern ceiling. Choosing one is a small decision, but it decides how the room looks once the building work is hidden. We ask which you would like during the survey and show you a sample where we can.

Rigid tube or flexible tube on the same route

Rigid tube

Brightest over a straight drop
Smooth mirror lining
Fixed lengths need cutting to fit
Needs a clear route through the loft

Flexible tube

Bends round joists and tanks
Easier to fit in a tight loft
Ridges lose more light
Best kept to a short run

Callout 4

Keeping water out where the dome meets the roof

The risk with any hole in a roof is the edge of the hole. A sun tunnel has a smaller edge than most rooflights, but the junction between the dome base and the roof covering still has to be watertight for as long as the house stands. That junction is the flashing, and getting it right is the part of the job we spend the most care on.

Flashings by roof type

On a pitched tiled roof the dome sits on a base, and a flashing kit lets the tiles around it overlap the base so water runs over the top, never under it. The kit is shaped to the tile. A plain clay tile, a concrete interlocking tile and a slate all want a different profile. On a flat roof the dome stands on a kerb, which is a low raised frame fixed to the deck, and the roofing membrane is dressed up the kerb and under the lip of the dome. Our page on flat rooflight kerbs and upstands explains the idea in more detail.

Either way the point is the same. Water must always have a downhill path that ends outside the house. If a flashing is poorly fitted, a leak often shows as a stain on the ceiling a metre from the tube, not at the tube itself, which makes it hard to diagnose after the fact. That is why we do not leave the roof until the flashing is dressed, sealed and checked.

Condensation inside the tube

The second job at this junction is to stop warm, damp air from the house reaching the cold tube. If it does, the damp condenses on the inside of the tube or on the underside of the dome and can run down onto the ceiling. A properly sealed diffuser at the bottom and an insulated sleeve around the tube in the loft cut that risk. Where the tube runs through a cold loft over a bathroom, we pay special attention to the seal at the ceiling and to a vapour barrier around the opening.

Working safely

Roof work needs proper access. We use edge protection or a scaffold tower where the pitch and height call for it, and the job is planned around the weather so that the opening is never left exposed overnight. A sun tunnel is a small unit, but a dry loft depends on how carefully the opening is closed up.

Callout 5

Pitched, flat or somewhere in between

Derby has the full range of roofs. Terraces built before the First World War often have slate or clay tile on a steep pitch, with a small loft above the landing. Interwar and post-war semis in the suburbs usually have concrete or clay tile and a larger loft. Newer estates on the edges have lower pitches and shallow lofts. A sun tunnel can fit any of them, but the details change from roof to roof.

Pitched roofs

On a pitched roof the dome goes between two rafters wherever it can. The aim is to leave the structure alone, so we choose a position that fits the gap between rafters and does not need to cut one. When the right route does fall across a rafter, a trimmer is added to carry the load. Cutting into the structure changes the legal footing of the job, and we cover that below.

Flat roofs

A flat roof, such as the roof of a rear extension, usually has a deck of boards or plywood with a membrane over it. The dome stands on a kerb that we fix to the deck, and the membrane is dressed to it. The tube drops through the roof build-up, which may be deep, and into the ceiling below. The tube length depends on the depth of the flat-roof build-up and any void below it. A short drop is a bright one, so we measure it before we promise anything.

Loft space in between

The loft is the part nobody sees, and it often decides the job. A tank, a chimney breast or a run of wiring might sit exactly where the tube wants to go. We look for these on the survey and plan the route round them. If a route is not practical, we say so and suggest another position, or another product such as a VELUX window where the roof allows.

Building Regulations and planning

Where a new tunnel means altering a rafter, the job counts as building work. Approval is then sought through the local authority or a registered building control approver, and the paperwork is ours to deal with. Swapping an old dome and tube like for like may still fall under Part L, which sets thermal limits for rooflights. Planning is a separate question. A house can usually take rooflights as permitted development, though conditions apply, and our planning guide sets them out. Flats and maisonettes sit outside those householder rights, a listed house brings consent rules of its own, and an Article 4 direction in a conservation area can take permitted development away. Ask Derby City Council before you commit.

The Derwent Valley Mills World Heritage Site runs through Derby at Darley Abbey, and old roofs near it are worth a conversation with the council before any work starts. Our guide to conservation rooflights covers what changes on a listed or protected roof, and a sun tunnel on a rear slope is sometimes far less visible than a window.

A short drop is a bright one, so we measure the run before we promise the result.

Four Derby roofs and how the tunnel meets each

The roof decides the flashing, the kerb and the length of the run.
Roof	Base	Flashing	Watch for
Slate terrace	Rafter gap	Slate kit	Brittle old slates
Concrete tile semi	Rafter gap	Tile kit	Tile profile
Rear extension	Raised kerb	Membrane dressed up	Deep build-up
Low-pitch estate	Rafter gap	Tile kit	Shallow loft

Callout 6

Sun tunnel or skylight for the space

The last choice is whether a sun tunnel is the right product at all. It is a fair question, and a firm that fits only one thing would give you one answer. We fit both, so the answer follows the space. Sun Tunnel or Skylight: Which Suits the Space? goes into the choice in detail. These are the main points.

When a sun tunnel is the better call

Choose a sun tunnel when the room is small, has no outside wall and sits under a loft. Choose it when you want daylight without a view and without a large opening in the roof. Choose it when the budget is tight but the dark spot is a daily annoyance. A sun tunnel is also less intrusive to install than a roof window, which needs a bigger opening, a new lining and often a finished reveal inside.

What we check from the landing to the roof

The dark spot: marked on the floor plan
Ceiling to roof: the drop the tube must cover
Loft route: tanks, joists and wiring in the way
Roof covering: slate, plain tile or membrane
Sky exposure: chimneys and trees shading the dome

When a skylight or roof window is better

A roof window suits a room with a sloping ceiling, such as a loft conversion, where you want a view, ventilation and a wide wash of light. A roof lantern or flat rooflight suits an extension, where the ceiling is high and the room is deep. A sun tunnel cannot open to let out steam or give a view of the sky. If either matters, a roof window or an electric opening rooflight will serve better. If you are converting the loft, remember that a roof window is the product that can count as an escape window, only within the height limit the regulations set, while a sun tunnel cannot.

Inside the room

The ceiling finish is the detail that people notice. We cut a clean opening, fit the diffuser ring and make good the plaster around it so the join does not show. A flat diffuser suits a modern ceiling and a domed one suits a ceiling with coving. In a bathroom we use a sealed diffuser with the right fixings, and in a landing we make sure the fitting does not catch on a loft hatch or a stair rail.

Light, heat and the loft around the tube

A tube passing through a loft should not become a path for cold air. We wrap the section in the loft with an insulating sleeve where the design allows, and make sure the existing loft insulation is laid back round it rather than squashed. At the ceiling the diffuser is sealed to the plasterboard. The thermal behaviour of the whole unit is the point of our energy efficient rooflights work, and the same attention applies here, even though a tunnel is a small unit.

Beyond the sun tunnel

Some houses need more than one product. A landing may take a tunnel while the loft conversion above it takes a roof window, and the rear extension may take a flat rooflight. Our service range lets us plan them together, which can save a second scaffold or a second visit. Plain advice at the survey beats a mismatch later.

Aftercare and the guarantee

When the job is finished you get a 10-year workmanship guarantee in writing, covering the way the unit was fitted. The survey and the written quote come first, and the notification follows during the work, so the day itself holds no surprises. If you are ready, the survey form is at the quote band below, and it takes a minute to fill in.

What people ask before fitting a sun tunnel

Are sun tunnels cheaper than skylights?

A sun tunnel usually asks for a smaller roof opening and less finishing work than a roof window, so the job can be simpler. The final figure still depends on the length of the run, the roof covering and the ceiling. We give a fixed written quote after a free survey rather than a guess over the phone.

What decides the cost of a sun tunnel in Derby?

The tube diameter, the length and bends on the route, the roof covering and the ceiling finish all move the cost. Extras such as a light kit or a vent fan add to it. We see the roof and the loft first, then write a single figure that holds on fitting day.

Will a sun tunnel work on a north-facing roof?

Yes, though the light is softer. The dome gathers daylight from the whole sky, not only direct sun, so a north slope still lights a landing or bathroom. Shade from a chimney, tree or neighbouring gable matters more than direction, and we check it during the survey.

Will fitting a sun tunnel go through Building Control?

If fitting a tunnel means changing a rafter, it is building work and goes through the local authority or a registered building control approver. Swapping an old unit like for like may also fall under Part L. The notification is ours to deal with whenever one is due.

Can you replace an old sun tunnel that has gone cloudy?

Yes. A clouded, cracked or discoloured dome can be replaced, and sometimes the tube and flashing too, if they are worn. We look at which parts are beyond repair, quote the replacement in writing and fit the new unit. Our misted rooflight page explains the thinking.

Does a sun tunnel need planning permission?

For a house the answer is often no, as it can go in without an application, but conditions apply. Flats are treated differently, and so are listed or protected buildings. Our planning guide lays it out, and Derby City Council can confirm for your street.

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Where do you want the light? Tell us in the form: the worktop, the stair, the desk.

No obligation. We survey before we price.
We cover Derby and 30 miles around.