The Cheapest Way to Replace a Conservatory Roof

There are three ways to read the question, and they give different answers.

The first is the lowest bill today. That favours polycarbonate, then glass, then a solid roof, and it favours repair over replacement whenever repair is possible.

The second is the lowest cost per year of use. Here a roof that costs more but lasts longer can come out ahead, though lifespans are only typical ranges, never promises. HomeBuilding gives a typical lifespan of 10 years for polycarbonate, and The Eco Experts give about 10 to 15 years for glass or polycarbonate.

The third is the lowest cost when you count comfort. A room too hot to sit in during July and too cold to use in January is a room you pay for and do not enjoy. That cost does not show on a quote.

Is it worth paying more for a roof you will not use much?

Probably not. If the conservatory is a store for plants, a spare dining space for a few weeks a year or a room that is rarely warmed, spending on top-end insulation buys little. If it is where you eat, work or sit through the winter, the extra for a better roof is often what makes the room usable.

The typical UK ranges for a whole conservatory roof replacement are £3,200 to £6,000 (MyJobQuote, Oct 2026) and £2,300 to £6,000 (The Eco Experts). The spread reflects roof size, shape and material, so keep it as a guide to what to expect, and let the survey fix your own figure.

Polycarbonate is a hollow plastic sheet, light enough that most frames can carry it and simple enough to fit quickly. If the existing roof is polycarbonate and the bars and frame are sound, swapping the sheets like for like is generally the least expensive way to get a new roof.

The saving comes from three things. The sheets themselves cost less than glass or a solid roof system. The fitting is quicker. And a light roof seldom needs any strengthening of the frame.

What does the lower price give up?

Comfort and life. Thin twin-wall sheets give modest insulation, so the room follows the weather. Rain is loud on them. Algae and dirt find their way into the channels over time, and the seals along the bars harden and split. HomeBuilding's typical figure of 10 years is a reminder that a low price now can mean another bill within a decade.

There are ways to improve a polycarbonate roof for little extra, such as thicker sheets or a better grade of bar and seal. The thicker the sheet, the more air is trapped between its walls, though a plastic roof will not match a solid roof.

If your roof is polycarbonate, our answer on polycarbonate conservatory roof lifespan shows the signs that it is nearing the end, and the page on moss on a polycarbonate roof explains cleaning.

Glass and solid roofs cost more at the start, and the money goes into things you can feel.

With glass, you pay for the double-glazed units, the bars that hold them and the work of fitting heavier panels. You get brightness, a clear view and a quieter room. Many glass roofs have a coating that reduces glare, and some clean themselves when it rains. The cost sits in the middle of the three.

With a solid roof, you pay for insulation, a covering such as tiles, an internal finish and often the frame work to carry it. You get a room that behaves like part of the house. The cost is generally the highest of the three.

Can I replace polycarbonate with glass for a modest extra?

Sometimes, but the frame decides. Glass is heavier, and older frames and bars were often built for lightweight sheet. If the frame needs strengthening, the apparent saving can disappear. Our answer on replacing polycarbonate with glass explains what gets checked first.

A solid roof is heavier still. A covering that weighs 15 per cent or more above the one it replaces brings in Building Regulations approval, and the Planning Portal suggests that an engineer or surveyor checks the structure beforehand. That adds to the cost, and it is better known before you start than discovered in the middle of the job.

If you are weighing the three materials in more detail, the full comparison is in our guide to the best conservatory roof material.

The least expensive roof is often the one you already have, mended. Many conservatory leaks come from a small fault, not a tired roof.

Is it worth repairing instead of replacing?

It can be, provided the fault is confined to one spot and everything else is sound. Common examples are a single cracked panel, a split or hardened seal along one bar, a lifted or damaged wall flashing along the house wall abutment, and blocked or leaking gutters. Each of those has a straightforward remedy, and none needs a new roof.

• One panel cracked or yellowed: replace that panel, if a matching one is available.
• A drip along a bar: renew the seal or capping.
• A leak along the abutment with the house wall: check the flashing first.
• Moss and algae: clean the roof by hand and renew the seals, never a pressure jet on old seals.

Our answer on replacing a conservatory roof panel and the page on conservatory roof wall flashing cover two of the most common repairs, and repair or replace a conservatory roof helps you decide.

A repair stops making sense when the damage is everywhere: sheets crazed or brittle across the whole roof, bars corroded or bowed, or the roof sagging between the bars. Spending on patches at that point just moves the leak around. If it is unclear which category yours falls into, the survey settles it. A repair also buys time: a few years of use from the existing roof can let you save towards the replacement you really want, instead of rushing into the first one on offer.

Whatever material you pick, the same handful of factors set the final figure. Knowing them lets you check any quote you receive, ours or anyone else's, is covering the right things.

• Roof area and outline, since a lean-to costs less than a complex multi-faceted front.
• The material and its grade, including coated glass or thicker sheet.
• Frame and base condition, and any strengthening needed.
• Access and scaffold, which depend on the height and the garden.
• Disposal of the old roof.
• Extras such as roof windows, vents or a new internal ceiling.

What needs checking on a conservatory roof quote?

Look for whether VAT and scaffolding are covered, and for the material and grade it names. Citizens Advice advice is to gather written quotes from at least 3 traders before choosing, and to compare what each one covers. A price much lower than the rest deserves a question about what has been left out, such as the old roof's removal or the flashings.

MyJobQuote's typical UK range is £3,200 to £6,000 (MyJobQuote, Oct 2026). The Eco Experts give £2,300 to £6,000. Both cover the whole job, so a small, plain lean-to sits towards the lower end and a large or complex roof towards the upper.

GOV.UK puts the standard rate of VAT at 20% for repair and re-roofing jobs on an existing home, so a quote that leaves it out looks lower than it is.

If cost is the first concern, the order of questions matters.

What should I decide first?

Start with the frame. If it is sound, you have the full range of options. If it is rotting, bowed or leaking at the joints, the first job is to put it right, because a new roof on a poor frame will not last either.

Next, decide how you will use the room. For occasional summer use, polycarbonate is a reasonable low-cost choice. For regular use, ask what a more comfortable roof would add, and weigh that against the extra price.

Then ask for a total in writing on each option you are weighing, so the difference in pounds is plain to see. Each follows the survey and is backed by photographs of your own frame and roof, so the reasons are clear, and you can set the extra cost of glass or a solid roof against what it adds in comfort.

Finally, think about the years ahead. If you plan to sell, a roof that suits the room can help the house. If you plan to stay and use the room daily, comfort tends to matter more than the first bill.

Our guide to conservatory roof replacement cost goes further into the numbers. For the frame, the question of whether a conservatory frame can take a solid roof is a good one to settle early.

To start, book a survey of your own conservatory, where the frame, bars and current roof are checked and photographed before any option is priced.