We are proud that our products have been verified by the Energy Saving Trust

Roof Replacement – Is It Worth It?

Roof Replacement

With any building material, there comes a time when they are looking tired and in need of upgrading. This is especially the case with roofs as they take a huge mount of punishment from the elements, whether in a warm country due to the heat or a wet country such as the UK. That is why a roof replacement is something many people consider in order to upgrade the performance and the appearance of their roof, breathing a new lease of life into a property. In this guide we are going to discuss roof replacements and whether they are really worth it, so you can decide on the best course of action for you and your home.

What is a roof replacement?

Firstly let's establish what exactly a roof replacement is. As the name would suggest, a roof replacement involves the process of removing everything on the roof down to the deck, which is then followed by putting on new layer of felt paper down and then the installation of new roof tiles.

An alternative form of roof renovation is roof repair, which is a better option than an entire roof replacement if a roof is not damaged on a large scale. 

When should I replace my roof?

There are a number of situations that will decide whether you will need to replace or roof, or simply undertake remedial works on your roof:

  • Roof age - if your roof is older than 20-25 years, this is often the recommended age in which a roof may require to be replaced.
  • Roof sagging if your roof tiles are beginning to sag or bow in the middle, this is something that could lead to structural damage and will need to be resolved through roof remedial or replacement.
  • Blown or missing tiles - any missing tiles is something that much be rectified as soon as possible by a remedial work, or if it is large scale then potentially a roof replacement. The same goes for blown roof tiles that have been damaged by moisture or moss growth. When moss grows, it absorbs moisture which causes roof tiles to lift away from the other roof tiles, causing significant damage.
  • Water damage if there a clear stains on your interior ceilings or walls, this is a direct indication that your roof may be leaking.

A roof replacement is a big task and is one that we all want to avoid if possible. If there is a structural problem with your roof such as it sagging or tiles missing, this must be addressed by a roofing specialist.

How much does a roof replacement cost?

A roof replacement is not a quick job. Roofcosts.co.uk estimate that the replacement of a whole roof on a semi-detached three bed property using plain slates costs on average £5550 which could grow to £8,250 on a larger property, using a natural slate roof tile.

This is due to all of the costs involved, not only from labour costs and scaffolding costs but of material costs from all new roof tiles.

The size of the property and the quality of the materials used will significantly change the price of a roof replacement, so it is extremely difficult to estimate the exact price your roof would cost to be replaced.

Advantages & disadvantages of a roof replacement

There are a number of advantages & disadvantages of a full roof replacement:


  • It can add value to your property, especially if your old roof was a significant eye-sore and had structural issues that would be off-putting to potential buyers
  • If leaks are being caused by a fault in the roof, then the quicker this is solved, the less 2nd hand damage and remedial costs will be incurred.


  • They can be extremely costly, often unnecessarily.
  • Replacing a roof is a large operation that takes many men and a large amount of disruption to your home.
  • There are cheaper alternatives that are suitable for many people that opt for a roof replacement

In summary, there are a number of situations in which a full roof-replacement is recommended, however not in all cases. Often, problems relating to moss growth, moisture & the appearance of a roof can be resolved without replacing your current roof tiles, which is a large scale renovation job. But what is the alternative? 

Roof replacement alternatives

If your roof is not having any structural issues such as a sagging roofline or large scale damaged roof tiles, then there are much more cost effective solutions to improving the appearance of your roof and protecting it from the elements.

It is a commonly held opinion that roof tiles are waterproof, however the truth is that they are porous, meaning they absorb moisture. This moisture leads to damage & decay of roof tiles as moisture is the route cause cracks to roof tiles. When these cracks appear, moisture and moss get between these cracks, which when the freeze they expand, causing the crack to get even larger. This continues until a large amount of moss covers your roof and it losses its integrity.

This is where waterproof technology comes in. The super hydrophobic technology developed by ProPERLA is the most advanced waterproof technology available in the UK today. This technology is contained in a range of roof coating treatments that protect roof tiles and enhance their beauty.

Applying a roof coating has a number of other benefits:

  • Allows moisture to repel straight off the roof tile before it absorbs into the material
  • Creates a self-cleaning surface as dirt particles are repelled from roof tiles with any rain fall 
  • Extends the lifespan of roof tiles as moisture is the biggest cause of roof tile failure
  • Makes it difficult for the growth of algae, lichens or moss on the roof tiles
  • Helps to prevent discolouration and salt efflorescence

ProPERLA's super hydrophobic technology is available for a range of materials such as roofs, exterior walls, wood & paving. In particular, there are two forms of waterproofing products for roofs; ProPERLA Water Repellent and RENOTEC Roof Coating.

While ProPERLA Water Repellent is a clear, invisible system that helps to protect roof tiles from water damage, RENOTEC Roof Coating is a popular choice with homeowners who want to transform their roof tiles without paying for a hugely costly re-roofing of their home. 

Both of these products come with a 10 manufacturers guarantee as they have been independently certified following rigorous testing.

RENOTEC Roof coating

The ultimate waterproof paint for roofs

  • Available in a range of popular exterior colours
  • Super hydrophobic
  • Highly breathable
  • Self-cleaning
  • Discourages moss, algae & lichens
  • Helps to extend the lifespan of the roof tiles
  • 10 year manufacturer's guarantee
Renotec Roof Coating
ProPERLA water repellent

The ultimate clear roof waterproofer

  • Creates an invisible protective barrier
  • Super hydrophobic
  • Highly breathable
  • Self-cleaning
  • Discourages moss, algae & lichens
  • Helps to extend the lifespan of the roof tiles
  • 10 year manufacturer's guarantee
Water Repellent

RENOTEC Roof Coating

Moss on roof


moss on roof tiles


moss removed


moss on roof tiles removed


RENOTEC is available in seven popular colours that are designed to match any property. Red Brown & Rustic shades are two of our most popular colours as they provide a beautifully traditional look to any property. For something more modern, Anthracite & Black Blue also prove extremely popular. These shades work perfectly with white rendered properties, and can really provide a huge kerb appeal. Roof coatings are the perfect product not only for painting roofs in an attractive colour, but providing long-term protection.

Renotec Roof Colours

ProPERLA Water Repellent

While the clear ProPERLA Water Repellent does not alter the appearance of roof tiles, as with any coating, dirt and grime must be washed off before it is applied. This means that the roof must be cleaned of any moss, dirt or algae by a professional before being coated with the ProPERLA Water Repellent, which creates the self-cleaning, waterproof barrier on the roof tiles that keeps them looking pristine for years to come. This is due to the moisture not being able to cause the moss growth and discolouration to the roof tiles that it can cause on untreated properties.

Once this is done, it is astonishing the difference it can make to a roof. The colour of the roof tiles beneath can provide a beautiful new look to your home, while offering a more natural finish to the roof tiles as they will still vary in shade from one another. This is particularly useful for older properties that benefit from a more rustic finish to the roof tiles.





Roof coating Vs roof replacement

You may be wondering how having a roof coating applied to your property will differ compared to having a roof replacement. Here are the main differences;

  • Time - a roof coating takes a fraction of the time of a roof replacement.
  • Cost - as we have discussed, a roof replacement can be a hugely costly renovation work to carry out due to the time it takes and the materials needed. Coating a roof is a cheaper alternative as it does not require the same level of materials as it is applied to the existing materials. Furthermore, it involves less labour costs due to the quicker turnaround.
  • Preservation - one of the key benefits of ProPERLA Water Repellent is that it does not affect the appearance of the original roof tiles. For older properties, a more natural and rustic look can be achieved by simply protecting the roof tiles with a waterproof treatment.
  • Ease - If your house is listed or in a conservation area then you need to check whether you will need any planning permission to re-roof your house.
  • Disruption - replacing a roof causes significant disruption. while a roof coating minimises this as it is applied to roof tiles by not disturbing the roof itself.
  • Protection - while a new roof will provide protection from the elements, eventually this will undergo the same deterioration process of your old roof tiles, eventually leading to damage once again.
  • Structural issue - as we have mentioned, coating your roof will not solve any structural issues with your roof. These should be resolved before you attempt to coat your roof. 

How to get your roof coated

We do not advise that you attempt to coat your roof using specialist treatment such as ProPERLA, as there are countless things that can go wrong.

We have a number of Approved Installers who have completed our ProPERLA training course, that ensures they can expertly apply our roof treatments treatments to your home. Please see our Approved Installers page here to find an installer in your area who can assess your property and provide a quotation.

We hope this guide has answered any questions you may have had regarding moss & how to prevent it. No matter whether you are a homeowner or a roof coating company. We are on hand to assist you with any question you may have.

Frequently Asked Questions

Q. How often should roof be replaced?

It is recommended that a roof should be replaced every 25 years, but in truth some roof are built to higher standards than others. If you roof is in good condition, you do not require a roof replacement for the sake of it. These are the properties that benefit from a waterproof roof coating the most, as they will have their lifespans extended for years to come.

Q. How long does a roof replacement take?

The size, weather and other factors will all play a large role in how long a roof replacement will take, but it could take up to a week to complete a full replacement.

Q. Does insurance cover roof replacement?

As with many insurance policies, homeowners insurance policies tend to cover roof replacements only if the damage was caused by a sudden accident such as a storm. Most damaged roofs are caused by long-standing moisture ingress causing them to decay over time. This means that it many be unlikely that you can claim for this, and is something you will have to pay for yourself.

Q. How long does roof coating last?

All roof coatings depending on their quality will vary in lifespan. The roof coatings at ProPERLA come with 10 year manufacturer guarantees, although they will likely exceed this. 

Q. Do roof coatings stop leaks?

Roof coatings help to prevent the ingress of moisture on roof tiles by creating a waterproof barrier. There can be some underlying structural problems that a roof coating cannot resolve which must be addressed also. The process of roof cleaning that is required before coating the roof can also help to prevent leaks.

Want to speak to one of our technical advisers for further advice on our range of roof coating treatments? They are always on hand to answer any questions you may have. Send them an email - info@properla.co.uk
© 2022 properla

    Please be assured we will not bombard you with emails but if you would like to unsubscribe at any time or would like to view how we use your data, please see our Privacy Policy here.