Replacing or Refurbishing an Existing Flat Roof For Your Home or Commercial Project

Discover What Happened When A Project Manager & Computer Scientist Came Home To Find A Caved In Kitchen Roof!

When Deb Cooper & Steven Battle bought their dream home they knew their flat roof needed replacing, they just didn’t realise how quickly until they came home to find water pouring into their kitchen!

Watch the video to discover how they did their research before choosing the right system and flat roofing contractor.

Deb & Steven, Homeowners, Bristol

Your Old Flat Roof Won’t Last Forever – But How Do You Know if it’s Time to Replace?

It’s a common question:

“How do I know when my old flat roof has had its day?”

And let’s be honest – it’s not easy to get a straight answer.

Ask a cobbler if you need new shoes, and he’s bound to say “YES!” – so if your roof can hold for a few more years, can you trust a roofer to tell you so?

Well, it depends on who you speak to.

The rogue traders and cowboys who give flat roofing a bad name will happily rip out a roof that could have been repaired – and leave you with a flimsy replacement that will almost certainly fail within 5-10 years (if not sooner).

Talk to a reputable roofer though, and you should get the true story:

• What’s wrong with the roof?
• Can it be repaired?
• How long will it last?
• And what will happen if the problem goes untreated?

Certainly, that’s how we work at Proactive Flat Roofing – going above and beyond the ethical standards set down by the industry to make sure you take the next step with both eyes open.

So does your flat roof need attention?

Flat roofing problems can fester for years before there’s a visible sign, like leaking water.This is because of how most timber flat roofs are built, they have a void between the external structural timber deck and the ceiling, this is normally filled with some mineral wool type insulation, so when the water seeps in, the insulation soaks up this moisture until it becomes so damaged through the constant assault from the English weather.

Below is just a few examples from a handful of flat roofs we have replaced over the years, none of the customers were aware water had been seeping in over the years and causing this structural and expensive damage!

Damaged flat roof structure due to leaking up stand flashing.

Damaged insulation and joists due to constant water ingress to this flat roof.

Water damage to a flat roof perimeter hidden from sight

So by the time you notice, the problem could be well-advanced. You might find the water has been rotting the structural deck, doing irreversible and expensive damage. This is more common than most flat roof owners realise.

In other words, a small sign could point to a serious risk.

So you should get in touch with us straight away – if you have any of the following tell tale signs:

The Bruising effects of the weather and global warming cause these common tell tale signs to check for

Building Movement

Building movement is caused by the 24 hour cycle your home goes through, that is further compounded by the seasons which have now become even more pronounced due to the effects of “Global Warming”.

Simply put, every 24 hours the building your flat roof is covering is expanding and contracting with the extremes of heat and cold, add to this the external effects of rain, frost and ultra violet light from the sun your flat roof is being attacked from all angles!

This constant and never ending relentless cycle causes stress in the waterproofing materials especially where they meet a wall of another surface, this is because different building materials expand and contract at different levels (Timber, brick and metal all have different co-efficient of expansion) causing splits and cracks especially where your flat roof joins another part of your building.

Cracks in the flat roof surface

…You see cracks in the roof, or the covering is damaged. These are caused by the effects of sunlight breaking down the surface in the summer months and then as the outside temperature cools the surface becomes brittle and cracks, this will lead to leaks and damage over time.

Damaged wall flashings

Another area of your flat roof prone to failure is anywhere that the flat roof meets an external wall or tiled area, this is often referred to as an "upstand flashing" or Wall flashing, in the same way the perimeters are prone to failure due to being under constant stress, the same is true of any flashing details, they suffer from the same fate as well which leads to splits on the bends add to this the fact that these often pull away from the wall, water seeps behind and works its way into the void and can cause damage if not addressed.

Repaired Flat Roof That Needs Replacing

Splits in the perimeter edges

Splits in the perimeter edges of your flat roof are a sure sign that the roof is well past it's sell by date, it's caused by the existing waterproofing material being under stress on where it is bent over and with age the oils in the material evaporate out and as a consequence becomes brittle, the result is splits open up as your roof goes through multiple 24 hour weather cycles.

Water Leaking Through Ceiling

Leaks in the ceiling

…Water is leaking through the ceiling. I know this is an obvious one, of course, however often you wont actually see the water leaking through inside your home for sometimes years! In reality your flat roof failed a long time ago on the outside and the water has been seeping in unseen to the void above your head, it gets adsorbed by any insulation and other building materials first, so you never get to see it ...until, the insulation just cant adsorb any more moisture and then you see the leak.

Ponding or Standing water

Ponding or standing water can be caused by a number of issues, it can simply be a result of something called “deflection” in the timber joists that support the structural deck (this is normally due to building movement over the years or sometimes a poor quality build and insufficient joist sizes) or more worryingly where your flat roofs structural deck has started to fail and collapse inwards.

This then just compounds the problem of “ponding” and accelerates the damage due to the weight of the water and you get a viscous circle of accelerated hidden damage and can in some cases lead to a “catastrophic” flat roof failure when the ceiling collapses!

Of course this is what happens in the extreme cases however as you will see from one of our case studies the home owners were unaware of what damage was going on above their heads, they knew it was bad just not how bad! “Out of sight and out of mind”.

Ponding water due to a damaged structural deck to the flat roof
The same flat roof after the water caused the ceiling to colapse

Interstitial condensation issues - The hidden enemy

Interstitial condensation is a common problem with flat roofs, especially when they are over a kitchen or a bathroom and where the flat roof void has not been ventilated properly (another very common issue!).

Without you needing a degree in physics, very simply it is caused when the warm moist air from your home rises up through the ceiling into the flat roof void and then when it meets a cold surface (normally the underside of your flat roofs structural deck) it condenses to form water droplets in the void.

The average family in the UK produces about 20 pints of water through condensation a DAY! That is a whole builders bucket of water from just normal living.

This roof was only two years old when condensation and poor ventilation rotted it from the inside.

This can cause damage to the timber structure over time and worse still produces mold and spores that can be damaging to your health, all hidden in the void so you cant see it happening!

It really is a case of “what you don’t know about can hurt you!” slowly over time.

In the worst situations It can also spread to walls and other surfaces in your home.

Blisters in your flat roof surface

Blisters under the top layer of a mineral felt flat roof are another common issue and often a sign of moisture and water that has seeped under this top layer of felt, once the sun heats up, the water trapped under this top layer heats up, becomes vapour and in the process forces blistering.

This can also happen with trapped water under the top layer when it freezes, because ice expands it creates a blister, in extreme cases this will split the top layer leading to further damage.

If your roof has any of these issues your next best step would be to have us carry out a flat roof survey and condtion report.

Your Next Step: Book Your FREE Flat Roofing Survey, Consultation & Written Condition Report [Value £250]

Proactive Flat Roofing: Residential & Commercial Flat Roofing Specialists

So what makes what we offer such a big deal?

Because, remember, there are “surveys” and there are surveys. An untrained salesman sitting in your living room trying to convince you to buy a flat roof from them is not a survey.

And a “self proclaimed” pro-roofer taking a casual look around and giving you a “back of a fag packet” price is not a survey.

A proper flat roofing survey takes time and focused effort.

Time to inspect the roof for signs of weakness or decay. Or to inspect the plans, to make sure the roof is designed to eliminate draughts and condensation. It’s a thorough process.

– And it’s all part of a consultation, where we’ll find out exactly what you want, and need, from the roof.

Book a Survey

One of our trained flat roofing surveyors will take a look at the roof, inside and out, first. They’ll check the structural deck, insulation and waterproofing layer to find the cause of the problem – taking a video and photos of everything they find as well as an access video for any scaffolding requirements and waste management should work be required and agreed.

They will then discuss their findings with you and give you straightforward advice about your options and including your thoughts and requirements in the design of any potential work. They will then take away all the information, write up their roof survey and upload everything to your cloud based job folder.

What you won’t get, is any of our trained flat roof surveyors sitting in your home taking up your valuable time trying to pressure you into signing a contract.

At this point the Estimating team take over, write up your flat roofing condition report that sets out your options clearly, in plain English as well as creating a proper detailed and itemised Flat Roof Action Plan and Quote, we have the most transparent pricing model in the industry, so you will have NO surprises! 

Typically the entire process from start to finish takes about 6 hours to produce (more on bigger projects) as well as vehicle running costs, fuel and overheads and that’s just for the average sized roof! £295 + Vat (£354) works out at just £59 per hour and we are not even going to charge you that! IT’S TOTALLY FREE.

In Summary This Is What You'll Get From Your FREE Flat Roof Survey

What gets replaced?

This will really depend on what you want and the condition of your existing flat roof.

The good news is that all of the above issues can be resolved and If your flat roof is structurally sound, we can simply add a new waterproofing top layer as a bare minimum.

We can do this with PVC Single-Ply, because it’s rigid enough to overlay without losing its shape. And, unlike other waterproofing systems, it works like “gortex” any moisture that gets trapped below the membrane can evaporate out because it breathes. Leaving the underside dry, and posing no threat to the roof deck.

This option is ideal for most customers, as it saves a lot of time and expense without compromising on quality or appearance.

Flat Roof Being Repaired

If the problem runs deeper though, and the deck is vulnerable, we’ll dismantle the whole roof and rebuild before we add the waterproofing top layer. Hopefully, your roof won’t need this more elaborate option – but we won’t know until we assess it.

If you are not quite ready to have a flat roof survey yet then you could request our free flat roofing guide.

Watch the video below to discover just what gets replaced and how.

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This free 24 page guide will cover all you need to know…

The Ultimate Guide to Choosing a Secure, Stylish Flat Roof

Discover the truth about waterproofing, insulation, fitting... and the hidden problem with guarantees. Your pack includes;

Flat Roofing Guide Step 1 (New)

About Proactive Flat Roofing

High-Quality, Energy-Saving Flat Roofs Built To Last

Proactive Flat Roofing is a reputable, reliable and professional flat roofing company currently covering London, the South East and South West regions of the UK.

Founded by flat roofing experts with over 4 decades of combined experience in the industry, we use our exceptional level of technical knowledge, combined with honesty, professionalism and skilled workmanship to ensure every customer gets a high-quality solution that works for their property – and stands the test of time! 

© 2024 Proactive Flat Roofing is a trading name of Vanguard Waterproofing Systems Ltd. 

Company no 12533066. Address: Castle Hill House | 12 Castle Hill | Windsor | SL4 1PD