Skylight Installation in West Bergholt
- Fixed quote before we start
- Roof never left open overnight
- 10-year workmanship guarantee
- Fixed quote before we start
- 10 years workmanship guarantee
- 25 years fitting rooflights
- Skylights only, not a general roofer
West Bergholt is a commuter village on the north-west side of Colchester, and its housing tells a consistent story: post-war estate development, generous rear plots, and a high proportion of houses that have had a single-storey flat-roof extension added across the back at some point. Kitchens, dining rooms, utility spaces. Rooms with one window at the far end and not much daylight in the middle. That is the job we get asked to solve here more than any other.
It is 16.3 miles from Ipswich in a straight line, about thirty-five minutes on the road.
A flat roof rooflight is a different construction, not a different shape
On a pitched roof the tiles shed water and the flashing kit ties the unit into that shedding. On a flat roof there is no slope worth speaking of, so the whole weathering strategy changes. The rooflight does not sit in the surface. It sits on a raised timber kerb, also called an upstand, built off the roof deck, and the waterproof covering is carried up the outside of that kerb and terminated above the level any water will ever reach.
Get the kerb right and the detail is genuinely durable. Get it wrong and you have built a permanent leak into the middle of a room.
Why the height of the upstand matters
The working figure is 150mm of upstand above the finished roof surface. That is not arbitrary. A flat roof is never perfectly flat and it will hold some water after heavy rain, and in this part of Essex the wind can drive rain across a deck and pile it up against an obstruction. If the covering only rises 40 or 50mm up the kerb, standing or driven water reaches the top edge of the waterproofing and finds the joint between covering and frame. At 150mm, with the covering dressed fully up the kerb and turned over the top, water simply cannot get to the seal. The frame then sits above the wet zone rather than in it.
Skylight installation in West Bergholt almost always begins with a look at the existing deck to see whether a proper kerb can be built off it, or whether the deck itself needs attention first.
Falls
The other half of the answer is designed falls. A flat roof should be laid with a slight slope so water runs off rather than ponding, and a rooflight in the middle of it is an obstruction water has to get around. The falls need setting out so water is directed past the kerb to the outlet, not gathering behind it in a puddle that sits for a week. Where a roof was laid dead level originally, which plenty of older extensions were, tapered insulation can build the fall in. That is a real cost and we would rather quote it than pretend it is not needed.
Ponding is the tell. If you can see a tide mark or a dried algae ring on your extension roof, that is where water sits. A rooflight kerb should never be inside that ring, and if the layout forces it to be, the falls get corrected as part of the job rather than left for the covering to cope with.
Flat glass or a dome
Both work. They behave differently and they look different, so it is worth choosing rather than defaulting.
- Flat glass units. Usually laid to a slight built-in fall, commonly around 5 degrees, so water and dirt run off one edge. They look considerably better inside and out, give an uninterrupted view of the sky, and the glass is a proper insulated unit. On a level roof a flat unit with no fall will hold water and dirt on the glass, so the fall is not cosmetic.
- Domed units. A dome sheds water from every direction by geometry alone, which makes it forgiving on a roof with imperfect falls. Polycarbonate domes are cheaper and lighter. They diffuse light rather than giving a clear view, and they discolour over time. Over a utility or a hallway, a dome is often the sensible answer.
Where the extension is the main living space, most people here end up on a flat glass unit or a roof lantern, which lifts the glazing into a pitched form on the same kerb principle and throws light much further into a deep-plan room. The kerb detail is identical. The difference is above it.
Three coverings, three different kerb details
What is on your extension roof changes how the upstand is terminated, and a fitter who details all three the same way will get one of them wrong.
- Single-ply membrane. Dressed up the kerb and heat-welded, with a welded detail at each of the four corners. Corners are where single-ply fails when it fails, so they are formed properly rather than folded and hoped over.
- GRP, glass reinforced polyester. The laminate is taken continuously up the kerb and over the top edge in one wet lay-up, so there is no joint in the waterproofing at the angle. GRP is unforgiving about damp or dusty substrates, and the top trim has to be bonded in, not screwed through the finished surface.
- Felt, torch-on. Built up in layers with the cap sheet carried up the kerb, and it needs an angle fillet at the base so the felt is not asked to turn a sharp 90 degrees. Felt cracks at hard angles under thermal movement. The fillet is the whole point of the detail.
All of that comes under flat roof skylight installation. Where an opening does not suit a standard size, we can set out a custom rooflight to fit the kerb rather than compromising the kerb to fit the unit.
Two ages of housing, one recurring job
West Bergholt did most of its growing after the war, when Colchester spread north-west and estate building filled the land between the old village core and the town. The core still holds its older cottages and a scatter of period property, but the volume of the village is post-war and later: semis and detached houses on generous plots, pitched main roofs in plain concrete tile, and the single-storey flat-roof extension across the back that so many of them have acquired since. That extension is why skylight installation in West Bergholt is so often a flat-roof job rather than a pitched one.
The pitched main roofs matter too, because a good number of these houses have shallow pitches and roomy lofts that convert well. Where the dark room is upstairs rather than in a ground-floor extension, the answer moves onto the tile and becomes a pitched roof skylight installation instead. We look at both at survey and tell you which one actually solves the room you called about.
Cold deck, warm deck, and the roof that sweats
The other thing worth understanding about an older flat extension roof is where the insulation sits, because it decides whether the roof stays dry from the inside as well as the outside. Plenty of extensions from the 1960s to the 1980s were built as a cold deck: insulation laid between the ceiling joists, a void above it, and the deck and covering over that void. In theory the void is ventilated. In practice, on a small domestic extension, it rarely is, so warm damp air from the kitchen finds the cold underside of the deck and condenses there. The homeowner sees a damp patch on the ceiling and reads it as a leak in the covering, when the water is coming from inside the room.
When we form a rooflight opening in a roof like that, we look at the build-up rather than just cutting through it. The modern approach is a warm deck, with the insulation laid above the deck and below the covering, so the deck stays warm and the dew point sits outside the structure. Where the covering is being disturbed for the opening anyway, lifting a tired cold deck to a warm one at the same time is the sensible moment, and it is far cheaper done then than as a separate job later. It also gets the roof to the thermal standard Part L asks for around a new opening, covered on energy efficient skylight installation.
Access, and what the survey checks
Post-war semis and detached houses here usually have side access, a gate down one flank to the back garden, which makes an extension roof easy to reach and scaffold. That keeps the job simpler and the price lower than a terrace with no side return. The survey itself is quick but specific: we lift a corner or probe the deck to see whether the timber is sound or has been sitting wet under a failed covering, check the fall and look for the ponding tide mark, confirm the covering type so the kerb is detailed correctly, and establish where the roof drains to. A roof that has been leaking slowly for years often has a soft deck, and a soft deck gets replaced rather than built on. Better found at survey than after the scaffold is up.
Getting a price in West Bergholt
We survey the deck, check the falls and the covering, then price once in writing. The figure holds unless the specification changes. Every installation carries a 10-year workmanship guarantee and is installed to current Building Regulations by installers with 25 years in the trade.
We work the same way in Colchester, Stanway and up towards Nayland. The full list is on areas we cover.
Request a fixed quote. A photograph of the extension roof taken from an upstairs window tells us a surprising amount before we arrive.
How high does the upstand need to be on my flat extension roof?
The working figure is 150mm above the finished roof surface. That gives the waterproof covering enough height to be dressed fully up the kerb and turned over the top, so standing water after heavy rain, or rain driven across the deck by wind, cannot reach the joint between the covering and the rooflight frame. Lower upstands are the single most common reason older flat roof rooflights leak. It is worth building correctly at the outset because it is very awkward to correct later.
My extension roof holds water in places. Can I still have a rooflight?
Yes, but the falls get corrected as part of the work rather than ignored. A rooflight kerb sitting inside a ponding area is a problem waiting to happen, because water lying against the upstand for days at a time is exactly the condition the detail is meant to avoid. On a roof laid close to level, tapered insulation can build in a fall that directs water past the kerb to the outlet. We check for the tide mark at survey and quote the correction openly.
Flat glass or a dome for a West Bergholt rear extension?
For a kitchen or dining room, flat glass or a lantern almost every time. A flat unit is laid to a built-in fall of around 5 degrees so water and dirt clear the glass, it gives a clear view of the sky, and the insulated glass unit performs properly under Part L. Domes shed water from any direction so they suit a roof with imperfect falls, and they are cheaper, but polycarbonate diffuses the light and discolours with age. Utility rooms and hallways are where domes still make sense.
My extension ceiling gets damp patches but the covering looks sound. What is that?
On an older flat-roof extension it is very often condensation rather than a leak. Many were built as a cold deck, with insulation at ceiling level and a poorly ventilated void above, so warm damp air from the kitchen reaches the cold underside of the deck and condenses. It shows as a patch that comes and goes with the weather. When we form a rooflight opening we can lift the build-up to a warm deck, insulation above the deck, which keeps the structure warm and stops the sweating. We check for it at survey.
Thinking about this job? We survey across Ipswich, Suffolk and north Essex and give you a fixed price before any work starts, with a 10-year workmanship guarantee.