Year-Round · Insulated · Opening Roof Option
Glass Conservatories with Opening and Fixed Glass Roofs
A glass conservatory is not a bigger version of the one your neighbour took down. The difference is what the roof is made of, how much of it opens, and whether the glazing was specified for British sun and British winters. Ours are designed, manufactured and installed by us, made to measure for your wall.
What makes a glass conservatory different
Traditional conservatories were built with uPVC frames, polycarbonate roofs and as much glazing bar as the structure needed. The result is a room that is bright but uncomfortable, and visually busy. A glass conservatory inverts that: slim aluminium profiles carry insulated safety glass with structural glazing, so the outer surface is flush and the frame almost disappears. You look at the garden, not at the frame.
Aluminium is what makes the slim sections possible. It is strong enough to span without deep mullions, it does not warp or swell, and it takes a powder-coat finish in any RAL colour that stays put in UK weather.
Opening roof or fixed roof?
This is the decision that shapes everything else, so it is worth taking seriously.
A fixed glass roof is simpler and costs less. With a solar-control unit it gives you a bright, quiet, thermally sensible room all year. It is the right answer if the conservatory is primarily an indoor space — a dining room, a study, a place the sofa lives.
A retractable glass roof slides its panels over one another and stacks them, opening up to 75% of the roof to the sky. Each section is driven independently, so one bay can be opened for ventilation without opening the rest. It costs more and it is the right answer if what you actually want is a terrace you can close — somewhere to eat outside in September without watching the forecast. The engineering behind it is on our retractable glass roof systems page.
You can mix them. A common layout is a fixed bay against the house and opening modules toward the garden.
Lean-to, gable and P-shaped layouts
The shape follows the house, not a catalogue. A lean-to conservatory — a single slope running down from the wall — is the most efficient use of space and suits bungalows, terraces and anywhere with limited headroom under the eaves. A gable ridge gives more height and a more formal look, and allows a total span of up to 14,000 mm. P-shaped and L-shaped layouts wrap around a corner of the house and are usually a combination of the two.
Projection runs from 1,500 mm to 7,000 mm on a single slope. Frontage length is unlimited because the roof is built from 1,200–1,750 mm modules.
Glazing, solar control and ventilation
The roof glass is normally a 21 mm insulated unit: a toughened outer pane, an argon-filled cavity and a laminated inner pane. A solar-control Low-E coating reduces solar gain and filters around 60% of UV, which protects furniture and flooring as well as keeping the room usable.
Where a section should be shaded rather than glazed, insulated aluminium composite panels in your RAL colour sit in the same roof. For strong south-facing exposure, external roof blinds above the glass stop heat before it reaches the glazing — considerably more effective than internal blinds, which stop the light after the heat is already inside.
Ventilation comes from the roof itself on an opening system, and from the side walls: frameless sliding glass, bifold doors or motorised guillotine glazing, so the walls can open as well as the roof.
Comfort in summer and winter
Two different problems with two different solutions. Summer comfort is about keeping solar energy out: coating, orientation, external shading, and the ability to open the roof. Winter comfort is about keeping heat in: the sealed unit, air tightness tested to EN 12207 Class 4, and a thermally broken frame.
Be realistic about heating. A glass room needs a heat source in December like any other room, and how it is heated affects whether the conservatory counts as thermally separate from the house under building regulations. We build the enclosure as a fully insulated winter garden and advise on the heating at survey; the heating itself is installed by your electrician or heating engineer.
Structure, wind and snow
Aluminium profiles are sized by structural calculation for the wind and snow loads at your location, with steel carriers where the span needs them and stainless-steel fixings throughout. No additional steel is required up to a 5,000 mm projection. Rainwater runs in concealed gutters inside the rails with a condensation channel beneath, so there is no external guttering cluttering the sightline.
Planning permission for a glass conservatory
Most single-storey rear conservatories fall within permitted development, subject to limits on depth, height and how much of the garden is covered — and the rules are different for listed buildings, conservation areas and flats. Building regulations exemption depends on floor area, glazing safety and thermal separation from the house. Our planning permission guide covers the thresholds.
What a glass conservatory costs
The main variables are size, roof type, glass specification and groundwork. Our conservatory cost guide sets out typical price ranges. Every project is quoted after a free survey and a 3D design, so the figure you get is for your wall, not an average.
Book a free survey and we will measure, check the wall and drainage, and design the panel layout before you commit to anything.
FAQ
Frequently asked questions
What is the difference between a glass conservatory and a glass extension?
Mostly regulatory. A conservatory is typically thermally separated from the house and largely glazed, which is what keeps it exempt from parts of the building regulations. A glass roof extension is part of the house and is built to full thermal standards.
Can a glass conservatory be used in winter?
Yes, with an insulated sealed unit, a thermally broken frame and a heat source. The glazing specification is what separates a room you use in January from one you close the door on.
How much of the roof actually opens?
Up to 75%. The panels slide over one another and stack rather than folding, and each section can be driven independently.
Do I need planning permission?
Usually not for a single-storey rear conservatory within permitted development limits, but listed buildings, conservation areas and flats are treated differently. We check this at survey stage.
Is an aluminium conservatory colder than uPVC?
No. Modern aluminium profiles are thermally broken, and the roof glazing has far more influence on comfort than the frame material does.
Can you build onto an existing conservatory base?
Often, if the base and any dwarf wall are sound and can carry the new loads. That is a survey question and we answer it before quoting.
Free, No-Obligation Quote
Get your free design and quote
Tell us about your project and we will send a free design and quote. Manufacture usually takes up to 6–8 weeks, and a standard house installation 1–3 days.
- Choose the roof and walls you are interested in.
- Add approximate sizes in millimetres.
- Leave your details — we prepare a design and quote.