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Fibreglass roofing is one of the most popular flat roofing systems in the UK. It is seamless, can be applied to virtually any roof build up and has a hard durable finish. However, this hardness makes most GRP systems very rigid. This rigidity can lead to some problems. Below we explore these potential disadvantages in detail.
Whilst fibreglass roofing is a fantastic option at times it can face some issues. Our blog post on fibreglass roofing problems looks at this in detail. These include roof cracking, alligatoring, pin holes, leaking, guttering and noise issues. So, let’s identify what these issues look like, why these problems occur and how they can be dealt with.
Unfortunately, cracking is often caused by poor roof installation. Cracking is easy to identify and looks like flaking and peeling of the roof’s top surface.
In warmer months the heat of the sun causes the GRP roof to heat and expand, then as the sun sets and the temperature drops the roof contracts back to its original size. The repetition of these movement of the roofs surface causes the fibreglass roofing to crack over time. The term given to this process is thermal expansion.
Once the damaged area of the roof has been identified the best solution is to replace this area. Roofers do this by cutting out the area affected by the cracking and then replace it with new fibreglass, resin and the protective top coat. It is, of course, essential that it is correctly installed this time so that the problem doesn’t reoccur. The best way to ensure it is done properly is by using an accredited GRP roofing company.
Once A GRP roofing system reaches the end of its lifetime it begins to lose its elasticity, this makes its appearance change and look cracked and wrinkled just like the skin of an alligator, which is where the term ‘alligatoring’ comes from. Sadly, if your roof has reached this stage there is no available solution and it will have to be completely replaced.
What is a Pinhole?
It can be difficult to identify pinholes on a GRP roof without getting up on your roof and inspecting it closely. Pinholes are literally tiny holes across the surface of the roof, which is were the terminology ‘pinholes’ comes from.
What Causes Pinholes?
Unfortunately, pinholes most commonly occur when not enough top coat is applied to the roofs surface during installation.
Why are pinholes a Problem?
On first inspection these pinholes may appear harmless because of how small they are, however they tend to lead to water ingress following heavy rain and high winds. The pooling of this water can then lead to water leaking through the pinholes on a GRP roof and damage the contents below.
Can they be fixed?
Yes, there is an effective way to solve the issue of pin-holing on a GRP flat roof. A fresh coat of resin can be applied to the area suffering from pinholes, this will then seal the tiny holes and prevent any of the issues discussed above from occurring.
What is Ponding?
As the name suggest ponging is when large pools of water congregate on a flat roof. If ponding occurs it places the roof at risk of leaking. Whilst it can be hard to spot whether there have been large pools of water on your flat roof there are other tell-tale signs you can lookout for, such as lighter or darker patches on your roof compared to the roofs original colour or what looks like rings wait a dirt stain around them.
Can Ponding be rectified?
Should you notice ponding on your roof it is best to contact a Fibreglass roof specialist immediately. The only way to rectify this issue is to board the roof with firings as at this point applying another layer of GRP coating is not an option.
What causes a roof to leak?
When a roof cracks water begins to pool in these areas making water ingresses. Unfortunately, cracks appear when a roof has not properly been installed. Cracks in the surface of the roof will lead to water ingress, these cracks are created if the roof has not been installed properly.
Can leaks be fixed?
Firstly, you need to identify where your leak is and the best way to do this is by going up onto the roof. You need to look for any cracks or pinholes, described above, as this will confirm where the leak is. After identifying your leak, the surveyor will follow a three-step plan of action; they will sand down the area, add a resin coat and final apply the topcoat (which will be a colour match to your roof’s original colour).
It is important to maintain your GRP Flat roof and give special attention to your guttering as they are known to become blocked so need to be checked regularly and cleaned. The risk of blockages in the gutter can be reduced by sweeping your roof clear of any leaves, dirt or debris that may have built up as this will prevent the rubble from any rainfall to pool and create water ingresses - which could then lead to leaking.
If your find that even with regularly clearing your gutters and sweeping your roof you are struggling for your own peace of mind it is worth contacting a roofing professional to come and evaluate whether you need a new guttering system fitted to your fibreglass roof.
Sometimes customers can report that they can hear creaking or cracking come from their fibreglass roof.
What causes these sounds?
These sounds could be caused by the change in temperature in the warmer months- as explored above thermal expansion can cause problems for GRP Flat roof systems, as when the roof heats and expands on a warm day and then cools in the evening the roof creaks as it contracts back to its original shape.
How to rectify this issue:
This is a normal process that is expected and steps can be take to reduce the negative side effects the expanding and contracting of the roof can cause. Roofers can use special expansion joints when installing a roof which help the flexibility of the fibreglass and reduce any noises the expanding and contracting process makes.
GRP roofing is an excellent flat roofing system and the issues we have discussed above will only happen for the following reasons:
• The GRP roof has reached the end of its life span.
• It hasn’t been properly maintained.
• The roof was not correctly fitted.
The best way to reduce the chances of these problems occurring is by ensuring you use a reputable Fibreglass specialist to install your roof. In addition to this it is important to regularly maintain your roof, e.g. cleaning the gutter, sweeping the roof cleaning and carrying out regular inspections to evaluate your roof’s health.