Which Polycarbonate Sheet Do You Need?

Which Polycarbonate Sheet Do You Need?

Since introducing our Clear Amber roofing sheet range in March, the most popular option by far are the polycarbonate sheets. We know that with the different options, thickness, colours and styles you can easily be overwhelmed by choice and not know where to start. So we are going to cover common questions about choosing polycarbonate for your project, comparing alternatives, installing polycarbonate and more!

So whether you are building a lean to roof, pergola roof or car port, polycarbonate sheeting will likely be one of the top roofing options you will consider and after reading this blog, you will (hopefully) know the best option for you. As a lightweight, stronger and arguably safer alternative to glass, polycarbonate is a cost-effective roof glazing solution that is easy to install whilst also creating stunning finish and so we will go over what it is, why it is good (and sometimes bad) and how to choose the correct roofing sheet for your upcoming project. 

What is a polycarbonate sheet?

Polycarbonate Sheets are popular compared to other lower grades of plastic sheets due to their durability and incredibly easy to install properties. As such, they are confidently used in millions of installations every year. 

Where can polycarbonate be used?

There are numerous uses that you may have already encountered today. Whether in a residential or commercial setting, it offers the flexibility to be utilized in a variety of applications such as canopy glazing, lean tos, carports, and protective barriers in public spaces. Its main purpose, and likely the reason you are reading this blog, is as a dependable roofing material. From lean tos and pergolas to greenhouses and orangeries, Polycarbonate reigns as the top choice for a diverse range of structures.

What types of polycarbonate sheeting are there?

The two types of polycarbonate sheets that Dry Verge & Roofline Direct offer: solid polycarbonate and multiwall polycarbonate.

Dont be put off by the amount of styles in the multiwall range. You can choose between Twinwall polycarbonate sheets and multiwall polycarbonate sheeting. These are the same thing, it's only the number of internal walls that set them apart.

Both solid and multiwall sheets boast durability and ease of installation, so your decision should be based on aesthetic appeal, budget, and strength.

What is Solid Polycarbonate?

Being 200x stronger than regular glass of equal thickness, solid polycarb sheets are virtually unbreakable, yet weigh only half as much. With a range of thicknesses from 2 to 12mm, including popular 6mm, solid polycarbonate sheets come in a variety of tints for all your needs, such as clear, bronze, opal, black, and patterned.

Have a look at the helpful Clear Amber Video below for more info:


What is Multiwall polycarbonate sheeting?

Multiwall polycarbonate sheets are made up of layers that create a honeycomb structure. This type of sheeting is widely used and is the most cost-effective option for polycarbonate, as well as providing excellent thermal insulation. Similar to Solid Polycarbonate sheets, multiwall polycarbonate is available in a variety of tints including clear, bronze, and opal. The most commonly used thickness for multiwall polycarbonate is 16mm.

What is Twinwall Polycarbonate?

Twinwall Polycarb sheets come in 3 thicknesses - 4mm, 6mm, and 10mm - providing a range of strength options for any roofing project/need. With just two layers, Twinwall polycarbonate offers the same quality as multiwall sheets but with just two layers- as the name suggests and is primarily used for smaller projects.

It is worth noting that 4mm & 6mm polycarb sheets are not recommended for roofing projects. Instead they are preferred as cost-effective plastic sheeting for smaller garden applications like cold frames.

So What is the difference between Twinwall & Multiwall?

Twinwall Polycarbonate Sheeting is extruding with two external layers and internal connectors. On the other hand, multiwall polycarbonate sheets have two external layers and then multiple internal layers, ranging from 3 layers total upwards.

The thicker the sheet the more walls they tend to have. 4mm, 6mm and 10mm thickness are considered to be Twinwall and 16mm, 25mm and 35mm are Multiwall. Thicker gauge sheets have better thermal insulation (lower U Value) Also thicker multiwall sheets tend to have greater sound reduction compared to the thin 6mm and 10mm, although this is less of a factor.


Benefits of Polycarbonate Sheeting

  • Virtually unbreakable
  • Lightweight
  • Easy to cut & drill into
  • Long-lasting clarity due to UV Protection
  • Insulating
  • Fire-resistant

Virtually unbreakable: A key benefit of polycarbonate sheets is their robustness and impact resistance which means they are virtually unbreakable!

Lightweight: Ease of installation is key when you are choosing a roofing sheet to use and a big part of that is weight. Heavy options like glass can cause handling challenges, especially when high up on a roof.

Long-lasting clarity: UV protection is important on clear roofing sheets to ensure long lasting clarity and light transmission. All of the Clear Amber polycarbonate sheets are UV protected on one or two sides to give a great roof lifespan! UV protected sheets are not to be confused with UV stable or UV resistant which are seen on some sheets (like PVC) and aren’t as effective.

Insulating: Polycarbonate naturally retains heat very well and so has great thermal insulation qualities. Multiwall polycarbonate in particular provides great levels of thermal insulation.

Sustainable: Polycarbonate roof panels are fully recyclable!

Fire-resistant: Polycarbonate is fire resistant and (unlike acrylic) is self-extinguishing.

Easy to cut and drill: Another area polycarbonate shines in is how easy it is to cut and drill. 

What are the disadvantages of polycarbonate?

Polycarbonate sheets have minimal drawbacks, making them a highly sought-after roofing option. The only drawback is their potential for scratching if not treated with care. However, this can be easily avoided with the use of protective film on both sides of the solid sheets during installation. Once installed, the protective film can be conveniently removed.

Can you bend polycarbonate sheets?

Yes, polycarbonate sheeting can be bent and installed on a curved roof. It is quite easy to install with curved glazing bars. As a rule of thumb, the thinner gauge sheets bend more easily.

What thickness of polycarbonate should I use?

When choosing a polycarbonate sheet thickness there are two main factors to bear in mind; strength & insulation. Quite simply, the thicker the sheet the greater the strength & higher thermal insulation. 

See below the common uses for each thickness as inspiration:

Solid Polycarbonate

2 mm – Wall protection, Secondary glazing

3 and 4mm – Screens, Bike shelters, curved dugouts, shed windows

5 and 6mm – Oak Pergolas, canopies, lean tos, gazebo glazing

8,10 and 12mm – lean tos, verandas

Multiwall Polycarbonate

4mm – cloches and temporary glazing (not suitable for roofing applications)

6mm - cold frames and greenhouses (not suitable for roofing applications)

10mm – potting sheets, pergolas

16mm – lean to, gazeboes, canopies, carports

25mm – lean to extension, garden buildings

35mm – conservatory roofs, orangeries, extensions

When choosing the correct sheet for your roofing project, it is always dependent on YOUR project’s factors, such as the location, wind, exposure, structure and so on.  So you are always best to make a judgement based on your project! 

Check the Clear Amber overview tables below for a complete comparison of colour types to further support your decision.

Axgard Solid Glazing Roofing Sheet Colour Benefits Guide

Axiome Multiwall Polycarbonate Roofing Sheet Colour Benefits Guide