Conservatory Costs, Alternatives, and Value
Compare uPVC, aluminium, and timber conservatories with orangeries and solid-roof extensions. Costs, pros, cons, and which adds real value.
Conservatories were the UK's go-to home extension for decades. At their peak in the early 2000s, over 200,000 were installed each year. But the market has shifted dramatically - today, homeowners are increasingly choosing proper extensions, orangeries, or solid-roof upgrades over traditional glazed conservatories. Here's why, and whether a conservatory still makes sense for your home.
Conservatory Types and Costs
By Style
| Style | Size | uPVC Cost | Aluminium Cost |
|---|---|---|---|
| Lean-to | 10–15m² | £5,000–£10,000 | £8,000–£15,000 |
| Victorian (faceted front) | 12–18m² | £8,000–£15,000 | £12,000–£22,000 |
| Edwardian (rectangular) | 12–20m² | £8,000–£16,000 | £12,000–£24,000 |
| Gable-end | 14–20m² | £10,000–£18,000 | £15,000–£25,000 |
| P-shaped (combined) | 20–30m² | £15,000–£25,000 | £20,000–£35,000 |
By Roof Type
| Roof | Cost (typical 15m² conservatory) | Thermal Performance | Lifespan |
|---|---|---|---|
| Polycarbonate | £6,000–£12,000 | Poor (hot summer, cold winter) | 10–15 years |
| Glass | £8,000–£16,000 | Fair (better than poly, still extreme) | 20–30 years |
| Solid (insulated) | £12,000–£22,000 | Good (usable year-round) | 30+ years |
Additional Costs
| Item | Cost |
|---|---|
| Base and dwarf walls | Usually included in quote |
| Heating (radiator extension or electric) | £300–£1,500 |
| Flooring (tiles, LVT, or engineered wood) | £500–£2,000 |
| Blinds (roof and side) | £500–£2,000 |
| Electrics (sockets, lighting) | £300–£800 |
| Building Regulations (if solid roof) | £500–£1,000 |
The Problem With Traditional Conservatories
Temperature Extremes
A glazed-roof conservatory is essentially a greenhouse:
- Summer: Temperatures regularly exceed 35°C, making it unusable for 3–4 months
- Winter: Temperatures drop rapidly when heating is off - expensive to keep warm
- Result: Many conservatories are used as storage rooms for most of the year
Limited Value
Estate agents consistently report that traditional conservatories add little to property value:
- Glazed-roof conservatory: 0–5% value (sometimes negative)
- Solid-roof conservatory: 3–5% value
- Orangery: 5–8% value
- Proper extension: 5–15% value
For more on which improvements deliver the best return, see our ROI guide.
Maintenance and Lifespan
Conservatories need ongoing maintenance:
- Polycarbonate roof panels: Discolour and crack (replace every 10–15 years: £1,500–£3,000)
- Seals and gaskets: Perish and leak (reseal every 5–8 years: £200–£500)
- Gutters and frames: Clean annually, check for algae growth
- Glass cleaning: Roof glass is difficult to access safely
After 15–20 years, most conservatories need significant refurbishment (£3,000–£8,000) or full replacement.
The Modern Alternatives
1. Solid-Roof Conservatory Upgrade
If you already have a conservatory, replacing the glazed roof with an insulated solid roof is the most cost-effective upgrade.
- Cost: £4,000–£8,000
- Impact: Transforms an unusable space into a comfortable year-round room
- Thermal performance: U-value drops from 2.0+ (polycarbonate) to 0.15–0.18 (insulated roof)
- Building Regulations: Required - the solid roof changes the building's thermal performance and structural loading. Apply via your council or through LABC
- Planning: Usually permitted development as the footprint doesn't change
Verdict: Excellent value if your existing conservatory base and frame are sound.
2. Orangery
An orangery combines solid walls and roof with large glazed sections and a central roof lantern. It's architecturally more substantial than a conservatory and performs closer to a proper extension.
- Cost: £20,000–£40,000
- Thermal performance: Good - insulated walls and roof with glazed lantern for light
- Planning: Usually PD (same rules as extensions)
- Building Regulations: Yes - treated as a standard extension
- Value added: 5–8% of property value
Verdict: The middle ground between conservatory and extension. Good for homes where a full extension isn't practical or the budget doesn't stretch.
3. Proper Extension
A standard single-storey kitchen extension or rear extension with a flat or pitched roof and large rear glazing (bifolds or sliding doors) delivers everything a conservatory promises - light, garden connection, open-plan living - without the temperature extremes and maintenance issues.
- Cost: £30,000–£60,000 (20m²)
- Thermal performance: Excellent - fully insulated walls, roof, and floor
- Planning: Usually PD for standard sizes
- Building Regulations: Yes
- Value added: 5–15% of property value
Verdict: The best long-term investment. Higher upfront cost but superior comfort, durability, and value.
4. Garden Room
A detached insulated garden building as a separate living/working space.
- Cost: £10,000–£30,000
- Pros: No impact on the main house, often no planning permission needed, quick installation
- Cons: Separate from the house (crossing the garden in winter), usually no plumbing
Verdict: Best for home offices and studios where separation from the house is an advantage.
Comparison Table
| Feature | Conservatory (glazed) | Solid-Roof Conservatory | Orangery | Extension |
|---|---|---|---|---|
| Cost (15–20m²) | £8,000–£18,000 | £12,000–£22,000 | £20,000–£40,000 | £30,000–£60,000 |
| Year-round comfort | Poor | Good | Good | Excellent |
| Value added | 0–5% | 3–5% | 5–8% | 5–15% |
| Lifespan | 15–20 years | 25–30 years | 30+ years | 50+ years |
| Building Regs | Usually exempt | Required | Required | Required |
| Maintenance | High | Low | Low | Very low |
When a Conservatory Still Makes Sense
Despite the shift away from conservatories, they can still be the right choice if:
- Budget is under £15,000 and you want covered garden-facing space
- You choose a solid roof - making it a year-round room
- You don't plan to sell soon - the enjoyment value outweighs the limited ROI
- You want a greenhouse-like space - for plants, a sun room, or seasonal dining
- Planning restrictions prevent a proper extension - check your options on the Planning Portal, as some properties have conditions that only allow conservatories
Making the Decision
Ask yourself:
- Will I use this space year-round? If yes, solid roof, orangery, or extension. If only in spring/summer, a glazed conservatory may suffice.
- Am I selling within 5 years? If yes, an extension adds more value. If staying long-term, choose for lifestyle.
- What's my budget? Under £15k = solid-roof conservatory. £15–30k = orangery. £30k+ = extension.
- Do I want it to feel like "inside" or "outside"? A glazed conservatory blurs the line. An extension is unambiguously part of the house.
Next Steps
- Define your budget and priorities - comfort, light, value, or all three?
- Get comparative quotes - conservatory, orangery, and extension for the same space
- Check our kitchen extension cost guide for detailed extension pricing
- Use our free calculator for a personalised extension estimate
- Read about which improvements add value before committing
- Browse extension costs by city for regional pricing
Frequently Asked Questions
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