How to Specify the Right Type of Single Ply Membranes for your Roofing Projects - IKO

In this CPD, we are going to introduce you to the different types of membranes available in single ply roofing market. We will also discuss the key factors to help you to specify the right type of single ply membrane meeting your project requirements.

SECTION 1: Who we are?

IKO in the UK

First of all we’d like to give you a quick introduction on IKO. For those of you who don’t recognise the name straight away, IKO is a well-established organisation in North America and Europe. As a natural progression, IKO acquired UK based Ruberoid & Permanite in 2000 followed by Marley Waterproofing shortly after. 

Login to record your CPD points

Since the acquisition, IKO has undertaken significant asset investment in manufacturing and warehousing at each of the 4 principal site locations.

The UK based headquarters is at Appley Bridge, Wigan, where we manufacture our Reinforced Bituminous  Membranes. In our Grangemill facility, we manufacture our Hot Melt and Mastic Asphalt waterproofing products. At Clay Cross, Chesterfield, we produce our single ply and  structural waterproofing membranes. Alconbury is our latest manufacturing plant for our thermal insulation products which has been operating since 2018.

Needless to say IKO are now the biggest manufacturer of roofing membranes in the UK.

What makes us different?

IKO offer complete waterproofing solutions from basement tanking to roofing membranes with a comprehensive system offer. We are the only roofing manufacturer who can offer Hot Melt, Mastic Asphalt, Cold Applied Liquid, Bitiminous and Single Ply membranes. Having all these product ranges in our portfolio, we can give you the expert advice on which roofing system is the most suitable for your project requirements.
As well as our broad roofing range, we also provide car parking, highways and bridge deck solutions.

SECTION 2: Why Single Ply?

Why Single Ply?

Unlike traditional roofing methods, single ply systems utilise a flame-free installation which is a massive advantage from a health & safety point of view.

Single ply systems also bring advantages to refurbishment projects as some single ply products are compatible with bitumen. Thanks to being a frame-free application, occupiers can safely use the building while the refurbishment works are taking place. 

Single ply is also a very lightweight material which offers maximum design flexibility to specifiers and can reduce the amount of steel work required to support the roof structure, potentially reducing the cost of the building.

Contrary to common misconception, single ply membranes are not only suitable for large commercial flat roofs but are also commonly specified for small scale projects where details and aesthetics are the key requirements.

They are also cost effective compared to bituminous and hot melt roofing systems and provide highly durable and long lasting performance with over 40 years of track record. 

New build meets refurbishment

Single ply was used on this block of apartments in London which combined refurbishment and new build. This project is a perfect example of the use of single ply in a residential project for the desired aesthetic look. It also demonstrates how single ply membranes can effectively replicate standing seam metal roofs.

In this project, the architect chose single ply waterproofing in preference to a zinc system. The reason they specified single ply was because it reduced installation time, provided simplicity in design detail whilst providing a cost effective, highly aesthetic and long term waterproofing solution.

Standing seam affect

These are the other examples of single ply replicating metal standing seam roofs.

SECTION 3: TYPES OF SINGLE PLY MEMBRANES

Although they can look very similar, there are different variations of single ply membranes and it is usual to come across with various membrane types in different markets. For example, Elastomeric membranes, such as EPDM, are commonly used in the North American market. Thermoplastic membranes such as PVC dominate the European market thanks to their flexibility and sleek finish.

All these membranes can be mechanically fastened or adhered. EPDM is typically installed by using adhesives or self-adhesive tapes, therefore it is more common for domestic projects, such as house and garage extensions. Unlike other membranes, EPDM is only available in black; therefore it wouldn’t be the right choice to meet different colour requirements.

PVC membranes: 

PVC membranes are the most popular membrane choice in UK’s single ply market. They are flexible, easy to weld and aesthetically pleasing. Although grey is the most dominant colour, they are also available in various colours .PVC membranes also have a track record of over 40 years in the UK market.

TPO membranes:

A fundamental difference between PVC and TPO membranes is that PVC membranes contain plasticisers in their formulation which give the membrane its flexibility. TPO membranes were initially developed to introduce an environmentally friendly membrane option without the use of plasticisers. However, TPO has struggled to become established in the UK market due to the perceived difficulty in the installation process. These membranes can be very sensitive to dust and other contamination which can affect the hot air welding process if the membrane is not prepared correctly. This can prevent the TPO membrane from welding adequately. Generally the membrane manufacturer would recommend the use of solvent preparation on the laps before hot air welding.

TPO membranes generally have a high coefficient of expansion and contraction resulting in the thermal movement during hot and cold temperatures. This in turn has an adverse effect on the aesthetics of the membrane. The thermal movement will remain during the whole life cycle of the membrane. Generally TPO membranes are not specified on projects where aesthetics are of importance, including those projects requiring standing seams. Similar to PVC, TPE membranes are also available in limited colours.

TPE membranes: 

At IKO, we looked at the available membranes on the market and decided on a unique membrane formulation using TPE (Thermoplastic Polyolefin Elastomer) which combined the positives of PVC (flexibility, ease of welding, aesthetically pleasing finish) and those of TPO (plasticiser and chlorine free formulation). As you can see from the pictures on this slide, TPE membranes provide an aesthetically pleasing finish and can be used with standing seams. They are also compatible with bitumen which makes them the ideal choice for refurbishment projects. Just like PVC, they can be manufactured in different colours.

Single Ply Membrane Characteristics

This table summarises the main characteristics of each membrane type. As you can see, PVC and TPE membranes are both easy to install and suitable for projects requiring complex detailing. Both membranes are also manufactured in the UK whilst EPDM and TPO membranes are imported in.

IKO Armourplan PVC System

Manufactured in the UK in IKO Polymeric’s Chesterfield plant, Armourplan PVC membrane is a tried and tested single ply solution. This membrane has a BBA life expectancy in excess of 30 years. 

Thanks to its flexibility, it provides an aesthetically pleasing look, especially when used in conjunction with standing seams. It is available in mid grey and slate grey as a standard but can be manufactured in other colour choices. 

IKO Armourplan P & PSG 

The use of 1.5mm or thicker PVC membrane is normally a requirement on extended 20 and 25-year guarantees. The theory is that it should last longer as it has a larger volume of plasticiser and is more robust due to its additional thickness. However, this is not always true.

Typically the top layer of membrane will contain a larger amount of UV stabiliser and fire retardant compared to the bottom layer. A 1.5mm membrane may be more robust so that it does not completely puncture when damaged, but once the top layer is broken, the lower layers are exposed to UV. In time, this will break down the membrane if the damage is not repaired.

At IKO Polymeric, we manufacture a special membrane for extended guarantees without increasing the thickness. Our Armourplan P membrane contains high-performance reinforcement to provide greater tensile strength. It also has equal quantities of UV stabiliser and fire retardant in the top and bottom layers of the membrane. This means the thickness of the membrane doesn’t need to be greater than 1.2mm, minimising the thickness build-up at cross-joints for an easier installation and detailing.

IKO Spectraplan TPE membranes

Manufactured in the UK by IKO Polymeric, Spectraplan TPE membranes provide easy installation due to their high elasticity. Tricky detailing is also easier with these membranes thanks to their ability of being able to weld at lower temperatures. 

If accidental damage occurs during installation, this can be easily rectified without the need of patch repairs. Thanks to the high polymer content, the puncture holes can be repaired by re-working the membrane by using a roller and a hot air gun. The repair becomes as strong as the membrane itself.

TPE membranes are also compatible with bitumen and polystyrene and fully recyclable which makes them the ideal solution for projects where environmental factors are the key.

SECTION 4: CASE STUDIES

In the next few slides, we are going to cover some case study examples including the different single ply roofing systems we have discussed earlier in this CPD.

This is the end of our CPD. We hope you found the information useful.

If you have any queries about IKO products presented in this CPD, please contact us on polymeric.marketing@iko.com or you can ring our technical team on 01257 488 012.

Thank you for watching.

Login to record your CPD points