If your conservatory is starting to look tired or dated, struggling with extreme temperatures, or you’ve noticed condensation and cold spots creeping in, it’s worth working out what kind of existing conservatory upgrade actually makes sense for your home: a full replacement, an extension, or something smaller in between.
Should You Upgrade An Old Conservatory, Or Replace It Completely?
The first thing you need to decide is whether you want to completely replace your existing conservatory. Dismantling it and starting again with a new, higher-performing structure is generally worth it if your conservatory is more than 20 years old.
In the last two decades, conservatory standards have increased dramatically, and a full-scale replacement is usually a noticeable step up in thermal performance, appearance, and security.
As you already have a conservatory installed at your home, replacing it will be easier than if you were building a new one from scratch.
Your existing foundations should easily support the new structure, so groundwork usually isn’t needed, and if you’re keeping the same size and style, planning permission generally isn’t a concern either.
If your conservatory is relatively new and you’re generally happy with how it performs day to day, a full-scale replacement probably isn’t necessary.
Often it’s just the roof causing the problems, an old, poorly glazed polycarbonate roof being the most common culprit, in which case upgrading that one element can solve most of the issue.
Upgrading Just The Roof On An Existing Conservatory
If it’s the roof rather than the whole structure that needs attention, there are three main options:
Fully glazed roof: brings in plenty of natural light and can be fitted with solar control glazing to help regulate heat.
Lightweight tiled roof system: usually made from slate, concrete, or composite materials. Our guide to replacing a conservatory roof covers this option in more detail, including tiled roof quotes if you’d like to compare pricing.
Polycarbonate roof: often seen as dated, but still the most cost-effective option, and modern versions perform considerably better than older ones.
Upgrading just the roof is one of the most popular ways to bring an existing conservatory upgrade in on a smaller budget, since it avoids touching the frame, base, or glazing you’re already happy with.
Can You Extend An Existing Conservatory?
If you need more space rather than just a refresh, extending a conservatory is often possible, and, as with a replacement, planning permission usually isn’t required. There are, however, certain restrictions when it comes to extending your home.
To stay exempt from planning permission when extending a conservatory, the finished structure generally must not:
Be more than one storey, or exceed 4 metres in height (3 metres if it’s within 2 metres of a boundary).
Extend beyond the rear wall of the original house by more than 3 metres (semi-detached or terraced) or 4 metres (detached) without notifying your council, though you can often go further, up to 6 metres or 8 metres respectively, via the neighbour consultation scheme, as long as no neighbour objects.
Cover more than 50% of the land around the property.
Extend from the side of the property by more than half the original house’s width.
Rules like these get complicated quickly, especially once a conservatory is already fairly large, so our full guide to conservatory planning permission is worth a read before you commit to a design. For the government’s own guidance, the Planning Portal covers the finer detail too.
What Should You Check Before Upgrading An Old Conservatory?
Before committing to any existing conservatory upgrade, it’s worth checking: the age and condition of the frame and seals, whether the base and foundations are sound enough for what you’re planning, whether a roof-only upgrade would solve the problem before you commit to a full replacement, and whether your plans fall inside or outside permitted development limits if you’re extending.
Getting a few quotes early on also helps, since a good installer will usually flag any structural issues during their initial survey rather than after work has started.
Replacing or extending your existing conservatory are both great ways to get more out of your home. If you’re still deciding on the right look, our guide to which conservatory style you should choose is worth a read next. Once you’re ready, fill in your details and one of our vetted installers will be in touch with a free, no-obligation quote.
Frequently Asked Questions
Can you upgrade an old conservatory instead of replacing it?
Often, yes. If the frame, base, and overall structure are still sound, a roof upgrade or new glazing can solve most of the common issues, draughts, condensation, overheating, without the cost of a full replacement.
When does a conservatory legally become an extension?
When it stops meeting the criteria for a conservatory’s lighter building regulations exemptions, generally once the roof and walls are no longer mostly glazed, or it becomes part of the house’s heated living space rather than a separate, glazed structure. At that point, it’s treated as a conventional extension and needs to meet full building regulations.
Can you extend an existing conservatory?
Yes, in most cases, and planning permission usually isn’t required as long as the finished structure stays within permitted development limits for height, depth, and coverage. Larger or more ambitious extensions can tip over into needing a full planning application, so it’s worth checking the specific limits first.
Is it better to replace or extend an existing conservatory?
It depends on what’s wrong. If the conservatory is old, cold, or generally underperforming but the right size, a replacement usually makes more sense. If the size itself is the problem and the existing structure is otherwise in good shape, extending is often the better and cheaper route.
Can you build an extension on an existing conservatory base?
Sometimes, but it isn’t guaranteed, many conservatory bases are built for a lightweight, mostly-glazed structure rather than a full extension’s brickwork and roof. A structural engineer or your installer’s building control team can confirm whether the existing base needs reinforcing first.
What should you check before upgrading an old conservatory?
Check the condition of the frame and seals, whether the base can support any planned changes, whether a roof-only upgrade would be enough before committing to more, and whether your plans fall within permitted development limits if you’re extending. A few quotes early on will usually surface any structural concerns, too.
