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What does a lean-to conservatory cost depend on?
A lean-to conservatory price depends on its width and projection, the height of the house wall it leans against, the roof material and pitch, the base and the glazing. This page does not print a figure, because we could not find two dated public sources that agree on one.
Last reviewed:Why the lean-to shape matters for price
A lean-to conservatory has one roof slope that runs down from the house wall to a lower front frame. It is rectangular in plan, with no faceted bays or gable peaks. For homes in Cheshire with a narrow garden, a bungalow, or a wall with first-floor windows close above the ground-floor ones, the lean-to is often the shape that fits.
QuoteZila is starting in Cheshire, with Crewe, Nantwich and Sandbach among the first towns, and anyone in the UK can post a job. We have not printed a lean-to price. We could not find two dated public sources that agree on a figure, so a number here would be a guess. Below are the measurements, materials and rules that decide what installers will quote.
The wall it leans against
Everything about a lean-to starts with the house wall. Installers will want to know:
- How high the roof can start. The top of the roof usually fixes to the wall with a wall plate. On a two-storey house, that has to sit below the upstairs window sills. On a bungalow, it has to sit below the eaves and gutter.
- How far it projects. The further the room comes out into the garden, the lower the front edge falls for the same slope, or the steeper the slope must start.
- The roof pitch. Roofing materials can have a minimum slope set by their makers. A shallow pitch may limit your choices.
- What is on the wall. Windows, an existing back door, airbricks, flues, outside taps, overflow pipes, drains and the electricity or gas meter can all affect the layout.
Because these points interact, two lean-tos of the same floor area can be very different builds. Ask installers to measure the wall and draw the side view, so you can see how high the front frame and the roof will be.
Lean-to quote checklist
| Item | What drives the price | Question for the installer |
|---|---|---|
| Width and projection | The floor area and the length of frame | What are the internal and external sizes? |
| Wall plate height | Fixes the top of the roof and the slope | Where will the wall plate go, and what is above it? |
| Roof covering | Glass, polycarbonate and solid roofs differ in weight, light and cost | Which roof, and what minimum pitch does it need? |
| Base | The ground must carry the floor, walls and frame | What foundations and floor are included? |
| Walls under the frames | Full-height glazing, dwarf walls or a solid side wall | Which walls are glass and which are brick? |
| Doors | French, sliding or a single door to the garden | Which doors, and on which side? |
| Gutter and downpipe | All the roof's rainwater runs to one front gutter | Where will the water go, and is the gutter sized for it? |
| Heating and power | An exempt room needs its own heating controls [S2] | How will it be heated and lit? |
| Making good | The join with the house wall and any paths moved | What finishing is included inside and out? |
| VAT | A business must register for VAT when taxable turnover goes over £90,000 [S5] | Is VAT included in the total? |
Size and planning
The Planning Portal says conservatories are covered by the same permitted development rules as other extensions [S1]. Those rights apply to houses rather than flats or maisonettes, and include a limit on the conservatory and other extensions covering no more than 50% of the land around the original house [S1]. A listed building, a conservation area or a property where the rights have been removed is different.
If the lean-to runs along a side boundary, close to a neighbour's window, or wraps round a corner, ask the council before you order. It is far easier to change the size on paper than after the frame arrives.
The separation rule and your back door
If your lean-to will go across the back door or a kitchen window, one rule matters more than any other. The Planning Portal says a conservatory is normally exempt from building regulations only if it is at ground level, under 30 square metres, separated from the house by external quality walls, doors or windows, and has its own heating with separate controls, with glazing and electrics that comply [S2].
The Planning Portal also says that if the doors between the conservatory and the house are removed, the exemption goes, the space must meet heat loss and ventilation rules, and the new opening needs approval [S3]. So keeping the old back door, or fitting a new external-quality door between house and lean-to, is part of what keeps the project simple.
FENSA says its scheme does not cover windows and doors in new conservatories [S4]. Ask the installer what paperwork you will receive instead.
GOV.UK: building regulations approval. QuoteZila is not affiliated with this organisation.
GOV.UK explains when building regulations approval is needed.
Living with a lean-to: sun, shade and use
A lean-to's long glazed front faces one direction, which shapes how the room feels. A south-facing lean-to can get very warm on a sunny afternoon. A north-facing one may stay cool. Ask the installer what glass and roof options they suggest for your orientation, and whether blinds or opening roof vents are part of the price.
Think about what you want the room for. A place for plants and a chair needs different heating, power and flooring from a home office or a dining space. Tell installers how you plan to use it, so the quote fits the room you want rather than a standard package.
Doors, steps and the garden
A lean-to often becomes the new route between the house and the garden, so its outside door matters. French doors open the whole front, sliding doors save space, and a single door keeps more wall for furniture. Think about which way the garden slopes, where the path runs and whether there will be a step down from the lean-to floor.
The floor level of the lean-to is usually set to match the house, which can leave a step down to the patio or lawn outside. Ask the installer what step, threshold and landing they propose, and whether a ramp or a level threshold is possible if anyone in the house needs one. A patio or path that has to be lifted and relaid to fit the base is extra work, so ask whether it is in the quote.
Replacing an old lean-to
Some houses already have an old lean-to, sometimes a timber or aluminium structure from decades ago. Replacing one starts with taking the old frame down and checking what is under it. The old base may be reusable, or it may be cracked, too thin or not level.
Ask each installer whether they plan to keep the existing base, and how they have checked it. A quote that reuses the base and one that replaces it are not the same job. If the old structure has a corrugated sheet roof, mention its age. If you do not know what the old sheets are made of, ask for them to be checked by a competent person before anyone breaks them up, and follow HSE's asbestos guidance. Do not cut, drill or break old roof sheets yourself.
Health and Safety Executive (HSE). QuoteZila is not affiliated with this organisation.
Jobs you might post
These are examples, not taken from real job posts.
- "Want a lean-to conservatory across the back of a bungalow, about four metres wide. The kitchen door opens onto that patio."
- "Old timber lean-to with a leaking plastic roof. Looking for a replacement on the same footprint."
- "Small lean-to wanted against a side wall for plants and a seating area."
Give the width of the wall and how far out you want it to come, say what is on the wall now, and include photos of the wall from the garden and of the ground where the base would go.
Comparing lean-to quotes
Citizens Advice says a quote is a fixed price and an estimate is only a guess, suggests written quotes from at least three traders, and suggests not agreeing to a deposit above 25% [S6]. Make sure every quote covers the same:
- Width, projection and wall plate height, shown on a side drawing.
- Base and foundations.
- Roof covering and pitch.
- Glazing, walls and doors.
- Gutter and rainwater route.
- Heating, lighting and sockets, and who does the electrical work.
- How planning and building regulations have been checked.
- Removal of anything old, stage payments and VAT.
Get quotes for a lean-to conservatory
QuoteZila is free for customers and local businesses [QZ1]. Up to five matched local businesses can send you a quote [QZ2].
Honest status: QuoteZila is new. We're starting in Cheshire, beginning with Crewe, Nantwich and Sandbach, and growing area by area. Anyone in the UK can still post a job or register a business. How fast you get quotes depends on how many local businesses have joined near you. Businesses can register and receive jobs straight away. We don't check insurance, qualifications or registrations, so please check these yourself before you hire.
Posting a job is not open yet
See glaziers for frames and glazing, builders for bases and brickwork, and roofers for solid roof options. The roof repair cost guide explains how roofers set out prices. For other shapes, see our conservatory cost guide.
Questions about lean-to conservatory prices
How much is a lean-to conservatory?
This page does not print a figure. Width, projection, wall height, roof type, base and glazing all move the price. Get itemised written quotes from installers who have measured the same wall, and compare them line by line.
Is a lean-to conservatory cheaper than other styles?
A single sloping roof and a rectangular plan are simpler shapes than a faceted Victorian end or a gable front, which can mean less frame and roof work. Whether that makes your quote lower depends on size, materials and the base. Ask installers to price the same footprint in each style if you are deciding.
Does a lean-to need planning permission?
Often not, for a house. The Planning Portal says conservatories follow the same permitted development rules as other extensions, for houses rather than flats or maisonettes, including a limit of 50% of the land around the original house. Ask the council if your site is listed, in a conservation area or near a boundary.
Is a lean-to exempt from building regulations?
It can be. The Planning Portal sets out conditions: ground level, under 30 square metres, separated from the house by external quality walls, doors or windows, its own heating controls, and glazing and electrics that comply. Outside those, building control is involved.
Can a lean-to replace my back door so it opens straight into the house?
The Planning Portal says removing the separation between house and conservatory takes away the exemption, so the room must meet heat loss and ventilation rules, and a new opening needs approval. Ask building control before you decide.
Does QuoteZila check the businesses?
No. We don't check insurance, qualifications or registrations, so please check these yourself before you hire. You can report a quote or a business from your job page.
This page is general information, not professional or legal advice. QuoteZila does not check Gas Safe, WaterSafe, NFRC, NICEIC or other registrations against the register on your behalf: look them up yourself.
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Related pages
- New Windows Cost: What Changes the Price. The Federation of Master Builders puts double glazing from £200 a window, and a window fitter at £25 to £35 an hour. Prices vary. QuoteZila does not set prices.
- Patio Door Replacement: Quote Lines to Ask. Replacing a patio door in Cheshire means a sliding frame in a named opening. Ask about the rollers, the cill, the glass and who certifies the work.
Sources
- QZ1: QuoteZila product fact. QuoteZila home and jobs-for-tradesmen copy.
- QZ2: QuoteZila product fact. QuoteZila FAQ and app README.
- S1: Conservatory mini guide (Interactive House), Planning Portal. Accessed 2026-10-25. https://interactive.planningportal.co.uk/mini-guide-type/conservatory
- S2: Building regulations: conservatories, Planning Portal. Accessed 2026-10-25. https://www.planningportal.co.uk/permission/common-projects/conservatories/building-regulations/
- S3: Interactive House FAQs, Planning Portal. Accessed 2026-10-25. https://interactive.planningportal.co.uk/faqs
- S4: Homeowners, FENSA. Accessed 2026-10-25. https://www.fensa.org.uk/homeowners
- S5: Register for VAT, GOV.UK. Accessed 2026-10-25. https://www.gov.uk/register-for-vat
- S6: Before you get work done on your home, Citizens Advice. Accessed 2026-10-25. https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/before-you-get-building-work-done/