Can I replace just one panel?

Yes, and it is a common job. The new unit is made to the measured size of the old one, so there are usually a few days between the measure and the fit. Expect a call-out or minimum charge on a single panel, which is why doing several together works out cheaper per panel.

Will a new panel match the old ones?

Close, but not perfectly, if the rest are twenty years old and the new one has a modern coating. A coated unit reads slightly differently in some light. On a conservatory where several panels have gone, doing a whole elevation at once avoids a patchwork.

Is this cheaper than a new conservatory?

By a very large margin, and that is the point of the page. Reglazing is a few hundred pounds a panel against many thousands for a replacement structure, and where the frames are sound it achieves most of what people want from the replacement.

Conservatories

Reglazing a conservatory: replacing the side panels

If the conservatory frames are sound, the glazed panels in them are replaceable on their own. Published guides put a conservatory side panel unit at roughly £120 to £250 each, more than a standard house window unit because the panels are larger and are often toughened. Replacing the glass does not require replacing the conservatory.

The same logic that applies to a misted window in a house applies here, and with more money at stake. A conservatory with failed panels is still a conservatory with sound frames.

What a sealed unit failure looks like here

It is the same failure as in a house window: the perimeter seal of the double-glazed unit gives way, the desiccant in the spacer bar saturates, and moisture condenses between the panes where you cannot clean it. The unit has lost its insulating value as well as its appearance, and it cannot be resealed in any lasting way.

What it has not done is damage the frames, the hinges or the base. See misted double glazing for the same job on a house window.

Conservatory panels fail sooner than house windows as a rule, because they are larger, more exposed, and go through a bigger temperature swing every day. Several failing within a year or two of each other is normal rather than a sign the conservatory is finished.

The upgrade worth making at the same time

The glass coming out is probably plain double glazing from whenever the conservatory was built. The glass going in costs very little more with modern coatings on it, and this is the one moment it is cheap to change:

Solar-control glass in the panels facing the afternoon sun, which does for the walls what a solar-control roof does for the roof.
A low-emissivity coating and a warm-edge spacer, which will noticeably outperform a twenty-year-old unit for the same labour.
Toughened or laminated where the panel is a critical location, which in a conservatory is most of them. Low-level glazing and anything in or beside a door has to be safety glass -- see safety glass requirements.

Where the roof is also tired, doing both together costs less than doing them a year apart, because the access and setting up are shared. See glass roofs and tiled roofs.

When the frames are the problem

Reglazing only works if the frames are sound, and on an older conservatory that is worth checking before you order glass:

Frames that have moved or bowed, so a new unit will not seat squarely and will fail early for the same reason the old one did.
Rotten timber at the cill or the bottom rail on a timber conservatory, which has to be repaired before any glass goes back in.
A base or dwarf wall that has settled, which is the one genuinely serious finding and is a structural job rather than a glazing one.

Short of those, a conservatory with failed panels and sound frames is a glass job, and anyone quoting to replace the whole structure should be asked to explain which of the three they have found.

Conservatory reglazing: common questions

Can I replace just one panel?: Yes, and it is a common job. The new unit is made to the measured size of the old one, so there are usually a few days between the measure and the fit. Expect a call-out or minimum charge on a single panel, which is why doing several together works out cheaper per panel.
Will a new panel match the old ones?: Close, but not perfectly, if the rest are twenty years old and the new one has a modern coating. A coated unit reads slightly differently in some light. On a conservatory where several panels have gone, doing a whole elevation at once avoids a patchwork.
Is this cheaper than a new conservatory?: By a very large margin, and that is the point of the page. Reglazing is a few hundred pounds a panel against many thousands for a replacement structure, and where the frames are sound it achieves most of what people want from the replacement.

Other conservatories

TrustedGlazing does not make, supply or fit windows and doors, and the prices above are published industry guides rather than our own. We match your enquiry to one local installer, who quotes and contracts with you directly.