How To Diagnose A Conservatory Leak

How to diagnose a conservatory leak

If your conservatory leaks you need to know how to diagnose a conservatory leak before damage occurs to your belongings, flooring, decor or worse, your home’s structural integrity. This guide will teach you how to diagnose a conservatory leak and how to resolve the problem.

How To Diagnose A Conservatory Leak & How To Repair It

diagnose leaking conservatory

Conservatories these days are constructed to withstand extremes in weather, high winds, and fluctuations in temperatures, however, due to the design of conservatories and the many components involved in the construction of a conservatory they can develop leaks over time.

When a conservatory does develop a leak it is important to stop it before it does damage to other parts of your home, knowing how to diagnose a conservatory leak as soon as it starts could potentially save you hundreds of pounds.

In a lot of cases, a leak will develop in a conservatory because of something simple like silicone sealant failing or a rubber gasket breaking down due to wear and tear which can result in a conservatory leaking but is reasonably simple to rectify.

Conservatory leaks can pose a serious risk to your family’s health and safety, electrical faults can develop due to the ingress of water which can develop into an associated fire risk, other health issues such as mold can cause or contribute to respiratory problems.

When a leak is first discovered it is a good idea to take precautionary measures such as using towels to absord any drips and buckets to catch as much water as possible.

You might want to attempt the conservatory repair yourself, if you do then you should wait until the next dry spell of weather if possible. Before attempting any conservatory repairs ensure that the area is thoroughly cleaned and dried before you reseal with a low modulus silicone.

Before attempting any D.I.Y repairs you should check to see if your conservatory has a current guarantee, most conservatories should have a 10-year manufacturers guarantee.

Best Glaze Conservatory guarantees offer protection for the conservatory base, the frames, and the roof, for ten years. Glass is covered for 5 years.

We do our best to ensure that there won’t be any issues with a ‘belt and braces‘ approach to all of our installations, however, should anything go wrong you have peace of mind that you are covered.

Leaking conservatory roof causes

Conservatory roofs are lightweight structures usually constructed from aluminium bars in which glazing panels, either glass or polycarbonate are seated, the glazing panels are held in place with plastic caps.

Conservatory repair cornwall

The glazing bars not only hold the glazing panels in place, but they serve as guttering for excess water and ventilation to prevent condensation.

A conservatory roof is made up of many parts, each part joins to another part to form the structure, these are areas that could develop leaks which is why a conservatory roof is usually the most common source of conservatory leaks.

The finial point is where the conservatory joins to the property, this is another common point of ingress, this is where the conservatory is sealed to the house using lead flashing. If the lead flashing is allowing water to enter the conservatory, you may need to replace the flashing completely.

Before attempting any repairs on the actual roof you should consider hiring a conservatory ladder, conservatory roofs are hazardous areas to be working and safety is paramount.

A leak that appears in the center of the conservatory roof could be due to the following:

  • Lifted ridge cap
  • Leaking bung at the end of the ridge
  • Slipped glazing panels
  • Cracked glazing panels
  • Failing silicone sealant
  • Perished seals
  • Incorrectly fitted parts
  • Poorly fitted glazing panels

Most of the above issues can be rectified relatively easily, glazing panels that are cracked, damaged, or slipped can simply be replaced completely, repositioned to create a waterproof seal on a leaking conservatory roof.

Another cause of leaking conservatory roofs is lack of maintenance which can cause a multitude of problems. Birds like to pluck the ridge brushes and use them to line their nests, this can also lead to leaks. Certain types of roof are prone to developing leaks, also as roofs get older they will need more maintenance to stop them from developing issues that cause leaks.

Polycarbonate and glass roof conservatories are the most prone to leaking, if you have a roof that is constantly leaking then it may be worth considering a replacement conservatory roof, solid tiled conservatory roofs do not suffer from leaks like their older style counterparts.

You now know how to diagnose a conservatory leak in the roof and how best to repair it, or whether you are able to repair it.

Leaking conservatory gutters & box gutters

Box gutters can be a problem for homeowners, older styled box gutters can be especially problematic due to the fact that they are usually much smaller than todays box gutter systems and have a tendency to block up easily. Blocked gutters can cause leaks when rainwater begins to build up and overflows.

The problem with gutters when the water overflows is that it can go behind fascias or even push behind seals allowing water to enter either the home or the conservatory, neither of these outcomes is good. A good maintenance regime can help to keep gutters free from leaves and other debris and prevent them from overflowing.

Another cause of a conservatory gutter leaking is poor installation or using the incorrect parts. Gutters that run around the outside of the conservatory can be knocked which can cause gutters to back up with water and overflow or leak from joints.

If this is the case with your guttering it is a simple enough job to refit the gutter and seal them in the correct position so that the water flows away properly and prevents them from backing up and overflowing.

You now know how to diagnose a conservatory leak caused by gutters and how to rectify them.

Conservatory Repairs cornwall

Leaking conservatory door(s)

Conservatory doors can leak because of a number of issues which are usually a simple fix. If your conservatory doors are allowing water inside of the conservatory then these are the things you need to check:

create a watertight seal around any door frames within your conservatory, but if your door is letting water into your conservatory it’s worth checking over the base of the frame to see if the water is pooling there, or check the rubber seals around the door and any glazing to see if they’ve split or perished at any point.

  • The door(s) is making a tight seal against the frame when closed
    The gasket around the door is intact and can make a complete seal
    The outer gaskets against the glass haven’t perished
    Drain holes in the bottom of the frame are not blocked

The conservatory door requires adequate drainage to allow water that enters through the seal to disperse and preventing pooling in the frame.

If the drainage is blocked, or there doesn’t appear to be enough, extra drainage could be created by drilling into the chamber and creating more exits for water to leave, this is especially handy if a door is not quite level.

Any seals on your door that are broken should be replaced as soon as possible to prevent water from entering through the sides of the door leaf and causing unwanted leaks.  You now know how to diagnose a conservatory leak around the doors, and how to remedy the problem.

Leaking conservatory walls and surrounding areas

We often receive reports of leaking conservatory walls from people looking for conservatory repairs in Cornwall. Walls that look wet or actually have water running down them are not leaking, the actual problem will be found where the conservatory joins the wall, usually because of cracked silicone sealant or poor sealing.

This is easily rectified by checking all of the sealant around the walls that are wet, remove all of the old silicone and re-seal them. Do not try to fill small gaps or cracks, remove the old sealant first.

Leaking conservatory roof

Conservatory windows leaking

Conservatory windows can be a source of water ingress because of a few common issues that allow moisture to enter the room, but not all of them are due to leaks. Conservatory temperatures fluctuate, particularly if they have a glass or polycarbonate roof. These changes in temperature can cause condensation to appear on the glass units which could seem like the windows are leaking.

Condensation is a common problem in older conservatories but it is quite simple to prevent. Opening a window will ventilate the conservatory and prevent a build-up of condensation and mold. Leaving some form of heating ticking over to regulate the temperature inside the space will also keep condensation moisture at bay.

If you know that condensation is not the cause of water entering the conservatory, then a window leak could be the problem, this could be caused by the following reasons:

Failing silicone sealant around the windows
Poor glass seal
Cracks in the frame on the welds
Failing gaskets on opening sashes
Draining holes in the frame blocked

Silicone seals tend to crack and fail when uPVC windows expand and contract. Some people pressure wash their conservatories which also breaks seals. Inspect the leaking windows for any of the issues mentioned above, now that you know how to diagnose conservatory leaks caused by windows, you should be able to fix them quite easily.

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Professional conservatory repairs in Cornwall.

If you have found the source of your conservatory leak and attempted repair but are still having problems trying to diagnose a conservatory leak, then maybe we can help. Sometimes sealing up leaks in joints or seals are only a temporary fix, if this is the case then find out how we can help you with your conservatory leak.

When you contact Best Glaze LTD, you will be speaking directly to one of our friendly, family-run team that deals directly with conservatory installations in Cornwall. Our team has over 20 years of experience installing and repairing conservatories as well as windows and doors.

We only use top quality materials and install the very best conservatory products by Ultraframe or Leka. With our proven track record we are super confident that you will not have any issues with one of our conservatory installations.

If you are a customer that has had a conservatory supplied and installed by Best Glaze LTD in the past ten years and has discovered a leak which is caused by faulty materials, then you have peace of mind that you are fully covered by our insurance backed guarantee.

Contact us and we can diagnose a conservatory leak for you and offer repair advice or a conservatory repair in Cornwall.

Call us today and we can discuss all of the options available to you. If your leaking conservatory is getting you down – we’re more than happy to help you choose an upgrade for your tired old conservatory roof. 
We have numerous conservatory replacement roof options that can transform a tired conservatory into a room you can enjoy all year round.

how to find & fix a conservatory leak

How To Find & Fix A Conservatory Leak in Cornwall

Prep Time: 1 hour
Active Time: 2 hours
Additional Time: 1 hour
Total Time: 4 hours
Difficulty: Medium
Estimated Cost: £0-£100

A conservatory leak can be more than just an inconvenience, it can damage your home, belongings, or worse cause injury to yourself or your family.

Most of the time a conservatory leak can easily be fixed if you know how to find and fix a conservatry leak it is a job that anyone with some D.I.Y knowledge could perform.

This guide will walk you through how to find and fix a conservatory leak yourself, or how to tell when you need professional help.


  • Cleaning rags
  • Hot soapy water
  • Low Modulus Silicone


  • Ladders
  • Scraper
  • Silicone Gun


Preparation is everything!

  1. If you have found a leak in your conservatory the very first thing that you should do is check to see if your conservatory is covered under warranty, most conservatories will come with a guarantee (usually for around 10 years).
  2. If you do not have a warranty then we will need to find and fix the conservatory leak which is the aim of this guide.
  3. Diagnosing the leak, we will need to find the leak.
  4. how to find and fix a conservatory leak

Check the conservatory roof for leaks first

  1. Check the roof for leaks first as this is the highest point and water will travel down.
  2. Is the leak coming in near the wall? If it is then you will need to check the lead flashing, this is a job for a professional.

    If the leak is coming from the middle of the ridge inside, then there are a few reasons a leak will occur here:
  3. The ridge cap has come loose and needs refitting.
  4. The ridge bung is perishing and allowing water to enter the ceiling.
  5. Glazing panels have slipped, they will need to be repositioned and sealed with low modulus silicone.
  6. Glazing caps have lifted and need refitting

Check The Conservatory Gutters For Blockages

  1. A blocked conservatory gutter will overflow and can cause leaks if the water spills behind fascias.
  2. Check that gutters are not blocked, have not been knocked preventing the water from flowing to the downpipe.
  3. Guttering is often overlooked as a source of conservatory leaks but it is an easy fix that will take literally minutes.

Check The Tops Of The Window Frames

  1. Where the roof meets the frames is a common point of water ingress. The ringbeam is usually bedded on a bead of silicone which can fail with the expansion and contraction of the conservatory frames.
  2. If this appears to be the source of your conservatory leak you can seal around the outside where the ringbeam meets the frames with low modulus silicone. Clean and dry the area first.

Check Window Frames, Joiners & Sealant Against The Walls

  1. If water appears to be entering the conservatory below the ringbeam height, checking the window frames, the joiners and the external sealant is the next thing you should do.
  2. Check window joiner bars are sealed
  3. Check the window frames for cracks
  4. Clean out drainage holes in the bottoms of the window frames
  5. Make sure windows are closing properly and gaskets are not perished
  6. Inspect the sealant where frames join the walls, where windows join together. Remove any cracked silicone, clean and dry the area and reseal.

Inspect Window Rubber Seals & Gaskets

Window seals, gaskets and glazing caps all perish over time. Older conservatory roofs are more prone to leaking due to this.

Gaskets should only be replaced by a professional, call a local repair company to replace gaskets, seals, glazing bars or glass.

Leaking conservatory Doors

Conservatory doors can leak over time for a number of reasons, check your doors and fix that leak!

  1. Make sure the door gaskets are intact.
  2. When closed a door should form a waterproof seal around the whole frame. If it isn't then the door may need adjusting.
  3. Conservatory doors can drop over time if they have not been toe and heeled correctly. This will need to be done by a professional.
  4. The drainage holes in doors can often block, clean them out, and make sure water can flow away through them.

Replacing Silicone Sealant On A Leaking Conservatory

Silicone breaks down over time, especially on conservatories as they expand and contract, this stretches, splits and cracks silicone sealant which in turn could allow water to enter your conservatory. Look for any split, cracked silicone, remove it and reseal.


Conservatory Repairs Can Be Dangerous

Conservatory leaks can be serious, however, if you do not feel confident working at height then you should always call a professional to repair a conservatory leak.

If you do not feel confident attempting a conservatory repair, leave it to a professional. If you do not know what you are doing, you could make things a lot worse.

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