Velux & Roof Windows In Dartford
Want more light in the loft, or tired of a roof window that leaks?
New roof windows, like-for-like replacements and flashing repairs on Dartford homes
Velux and roof windows in Dartford are mostly about lofts. With so many terraces and semis in the town, going up is often the only way to gain a room, and a roof window is the cheapest way to get daylight into it. We fit new ones into existing roofs, replace tired older units, and fix the flashing leaks that make people think the whole window has failed. Velux is the name most people use for any roof window. We fit that brand and other good makes, and we'll tell you plainly which suits your roof. Whichever you choose, the window is only as good as the way it's flashed into the tiles around it.
Get A Roof Window Quote
A roofer rings you back to arrange a visit.
Why fit a roof window rather than a dormer
A dormer gives you headroom. A roof window gives you light for a fraction of the cost and disruption. For a lot of Dartford lofts, that's the better trade.
01
Daylight from above
Light through a sloping window reaches deeper into a room than light through an upright one of the same size. In a loft with low eaves, two well-placed roof windows can make the space feel far bigger than it measures.
02
Usually no planning application
Most roof windows count as permitted development if they meet a few simple limits. That means no planning fee and no eight-week wait for a decision. We check your house against the rules at the survey and flag anything that puts it outside them.
03
Often fitted in a day
Swapping a like-for-like unit, or fitting a new window between existing rafters, is often a single day's work. Your roof is open for hours rather than weeks, and you won't need to clear out the room below.
04
Ventilation built in
Modern roof windows have a vent bar in the frame, so damp air can get out without the sash being open. In a loft bedroom or a bathroom under the slope, that small detail makes a real difference to condensation.
05
Escape options for loft rooms
In a loft conversion, a roof window may need to double as an emergency escape. Top-hung and escape-type windows open wide enough for that. Building control decides what's needed; we make sure the window we fit matches it.
06
Blinds made to measure
Blackout, venetian and insect screens are made to each window's size. Fitting them at the same visit saves a second trip, and in a south-facing loft a good blind does more for summer heat than anything else you can buy.
1,000+
Roofs repaired, renewed and rebuilt
10 yrs
Written guarantee on every re-roof
5★
The only rating anyone has left us
£0
For the survey and the written quote
Lofts in a town of terraces and semis
Over 90% of Dartford homes aren't detached, and many of those are terraces and semis where building out sideways simply isn't possible. So the loft gets converted. On a hipped 1930s semi, the kind you'll find round Princes Road and Shepherds Lane near us, the slopes are small and a roof window has to sit carefully between the hips and the chimney. On a terrace, the rear slope usually takes the windows and the front stays plain. Either way, the window has to work with the roof you've got, not one from a brochure.
Then there's the newer stock. The Bridge, where George Wimpey built over a thousand homes on the old Joyce Green Hospital land, and the 2000s estates out towards Ingress Park have been lived in long enough that some owners are now looking up for space. Many roofs of that era are built on trussed rafters. Those can't be cut and trimmed the way a traditional cut roof can, so a new window either fits between the trusses or needs an engineer's design. We check that from the loft before we quote.
"A good share of the leaking-Velux calls we take turn out to be a perished flashing, or condensation running down the glass, rather than a failed window."
Fitting a roof window, step by step
- 1
Measure up inside and out
We check rafter spacing from the loft, the tile or slate outside, the roof pitch and where the window will sit relative to the floor. Those four things decide what size and type of window will actually work.
- 2
Fixed quote with sizes named
You get the window make, model and size, the flashing kit, any lining or blinds, and our labour, all in writing. If building control is needed because rafters are being cut, the quote says so.
- 3
Protect the room below
Dust sheets go down inside and anything delicate gets moved. Most fitting happens from inside the loft with a roof ladder outside, so a single window at a sensible height often doesn't need scaffold.
- 4
Open the roof
Tiles or slates come off around the opening, the felt or membrane is cut back and, if the window is wider than the rafter gap, rafters are trimmed with new timbers to carry the load either side.
- 5
Frame, flash and collar
The frame is fixed to the battens and rafters, the insulation and underfelt collars go round it, and the flashing kit goes on course by course. Tiles are refitted tight to the flashing.
- 6
Line and finish inside
We can board and line the reveal, or leave it ready for your own plasterer. Either way the gap round the frame gets insulated so it doesn't turn into a cold, damp spot in winter.
- 7
Test, clear and explain
We open and close the sash, check the vent, run water over the flashing and clean up. You get the manufacturer's paperwork for the window and photos showing how it was flashed in.
10
Years' cover on a new roof
1,000+
Roofing jobs finished
Paperwork in your hand on the last day. Not posted out "in due course".
What the 10 year guarantee on a re-roof actually covers
Re-roof a house in Dartford with us and you get 10 years of cover on the workmanship. It's a written document. It has your address on it, lists what was done, and is dated the day the roof is signed off. If water gets in because something was fitted wrong - a batten, a fixing, a lap, a flashing - a roofer comes back and puts it right. You don't pay for that.
Why are we happy to promise ten years? Because of how the roof goes on. Every tile or slate is mechanically fixed to BS 5534, the current British Standard. Ridges and hips are fixed too, not just sat in mortar. A breathable membrane goes down first. Where a roof meets a wall, a chimney or the house next door, it gets proper lead or a tested dry system. Shortcuts there are what make a guarantee expensive, so we don't take them.
Tiles, slates and membranes also carry the maker's own warranty. Those vary by product, and your paperwork tells you which ones apply. If a job is too unusual to guarantee in the normal way, you'll hear that at quote stage.
Choosing a roofer to fit roof windows in Dartford
Roof first, window second
Roof windows go into roofs, so the person fitting yours should be a roofer who understands tiles, battens and membranes, not just someone who has installed windows. Most leaks round roof windows come from a flashing kit that's been trimmed, misaligned or fitted to the wrong tile profile. Ask how they'll flash the window into your particular roof, and what they'll do if the tiles around the opening turn out to be brittle.
Honesty about the structure
A single window that fits between rafters is straightforward. Anything wider means cutting and trimming rafters, and on a trussed roof that usually needs an engineer. A decent roofer will spot which you have from the loft hatch and tell you before quoting, rather than finding out halfway through with your roof open. If nobody has put their head in your loft, the quote is a guess.
Straight answers on brand and paperwork
Plenty of roofers fit Velux windows, and plenty fit other makes that perform well. What matters is that the window is a genuine product with the maker's own guarantee, fitted with its matching flashing kit. Be careful with anyone claiming a special status they can't show you in writing. Ask for the model number on the quote so you can look it up yourself.
Which type of roof window suits you?
Four common ways to get light in through a roof. The first two are what most people mean when they say Velux.
| Comparison point | Centre-pivot | Top-hung | Fixed rooflight | Flat-roof lantern or dome |
|---|---|---|---|---|
| How it opens | Rotates on a hinge halfway up | Swings outward from the top | Doesn't open | Fixed, or with an opening vent |
| Cleaning the outside | Turn the sash and clean from inside | Harder to reach the outer pane | Ladder or roof access only | From the flat roof |
| Works best | Above head height, over furniture | Low down, where you want to look out | Stairwells, landings and hallways | Single-storey extensions with flat roofs |
| Escape use | Not usually suitable | Escape versions available | No | No |
| Relative cost | Lowest of the opening types | More than centre-pivot | Lower, no opening gear | Varies widely with size and glazing |
| Planning | Usually fine within the 150mm limit | Usually fine within the 150mm limit | Usually fine within the 150mm limit | May stand proud of 150mm, check first |
Replacing an old roof window
Older roof windows tend to fail in the same few ways. The seal between the panes goes and the glass mists up, the hinges stiffen, the timber frame rots at the bottom where condensation runs, or the flashing perishes. Not every one of those means a new window. A failed glazed unit or a tired flashing can often be replaced on its own.
When the frame itself is gone, many older windows have a modern equivalent in the same opening size, so the tiles and lining around it barely need touching. If the slope around the window is in poor shape too, it may make sense to deal with the roof first.
Roof repairs in Dartford
Roof window costs in Dartford
Supplying and fitting a new Velux-type window in an existing roof typically costs £900 to £1,800. Where you land depends on the size, the glazing, whether it opens by hand or electrically, and whether rafters need trimming. A like-for-like swap in an existing opening usually sits toward the lower end. Blinds and internal lining are priced as separate lines.
Roof window questions from Dartford homeowners
Do I need planning permission for a Velux in Dartford?
Usually not. Rooflights are permitted development if they stick out no more than 150mm from the roof slope, sit no higher than the highest part of the roof, and, on a side-facing slope, are obscure-glazed and either non-opening or set over 1.7m above the floor. Flats, listed buildings and conservation areas are different. Anyone in a listed house or inside the Town Centre conservation area should check with Dartford Borough Council first.
Do roof windows need building regulations approval?
If fitting the window means cutting and trimming rafters, building control will normally need to be involved, because that's a structural change. A like-for-like swap in an existing opening usually isn't. In a loft conversion, the windows form part of the wider building regulations application for the conversion. We'll tell you at the survey which applies to your job.
Why is water dripping off my roof window?
Often it's condensation, not a leak. Warm, damp air from a loft bedroom or bathroom hits the cold glass and runs down to the frame. Open the vent bar, run an extractor in bathrooms and see if it stops. If water appears on dry, cold days, it's condensation. If it only comes in during wind-driven rain, the flashing is the likelier culprit.
Can a roof window go into a slate roof?
Yes. There are flashing kits made for thin, flat coverings like slate and others made for profiled tiles. Using the wrong one is a common cause of leaks. Old slate can also be brittle, so we allow for a few replacement slates around the opening on the quote, rather than surprising you with them later.
Can you replace my roof window without redecorating inside?
In many cases, yes. If a modern window is made in the same size as your old one, the frame comes out from inside and the new one goes into the same opening. The inside lining is usually left alone, though a strip of paint or filler round the frame may need touching up once we've finished.
My address says Bexley but I live in Joyden's Wood. Which council do I check with?
Joyden's Wood homes often carry a DA5 Bexley postcode, but the estate sits in Dartford Borough, so planning questions go to Dartford Borough Council. Crayford, Bexley village and Erith come under the London Borough of Bexley, and Swanley is Sevenoaks District Council. If you're right on the edge, check by address, because the boundary doesn't follow postcodes.
Related: Re-roofing · Roof repairs · Flat roofing
Reviews from Dartford homeowners
Every review left for us so far has been five stars. We're adding them here as they come in.
Reviews only tell you so much anyway. When a roofer comes out to Dartford, ask to see photos of a recent job on a house like yours. A good roofer will have plenty and won't mind you asking.
Bring some daylight into the loft
Tell us where you'd like the window and roughly what the room is for. We'll check the roof, the rafters and the planning rules, then send you a written price.