Skip to main content

How to accessorize for maximum effect - Part 2: Outdoor Use

Continuing our series looking at the use of insulation accessories, in this entry we will be looking at how to protect insulation for external use.

The basic problem with the majority of thermal pipe insulation products is that you cannot use them outdoors; notable exceptions are premium products such as Eurobatex R which can be used externally without painting due to its protective polyolefin skin, but comes at a price premium compared to other products, or high temperature EPDM rubbers such as Eurobatex AT which are inherently UV stable but lacks the thermal values to be used for frost protection on smaller pipes (this product is intended mainly for use on solar pipework where the thermal requirements differ from conventional thermal insulation products).

These products aside, the more common closed cell flexible foams such as Eurobatex Pipe InsulationClimaflex Pipe Insulation or Armaflex Pipe Insulation will degrade in sunlight. Typically, polyethylene pipe insulation (such as Climaflex) can last for a number of years outdoors without protection so this can be a low cost option in the right situation. Nitrile rubbers (such as Armaflex or Eurobatex) do not tend to fare as well outdoors as a polyethylene might, and given that the thermal values are so close it makes more sense to use polyethylene if you are looking for a cheap option you will need to replace after a few years.
The simplest way of protecting these sort of products outdoors is to use a flexible, water based paint such as Union Colour paint. It is important that it is a flexible paint as flexible foam pipe insulations expand and contract with variations in temperature, so a normal paint will crack and flake off. You will normally want to apply two coats, and once dry this product will protect the insulation from UV damage. It does not offer a great deal by way of mechanical protection, but in the majority of domestic situations will be sufficient. 

Foil faced products such as Kingspan KoolthermSager Pipelane or Rockwool Rocklap present a different kind of problem. Aluminium foil is not suitable for external use, again due to UV stability, but also because it is not waterproof so the insulation underneath will get wet. Wet insulation is actually worse than no insulation at all; insulation works by trapping air (which is an insulator). If you replace that air with water (which is a conductor) then your pipes will actually freeze quicker than if they had no insulation at all.

So, how do you protect it if you want to use this kind of product outdoors? The thing to use is a product such as Plysolene PIB (Polyisobutylene) Sheet. This is a strong but flexible jacketing product that can be used over a variety of insulation types. It is applied by using a welding agent to bond all overlaps and butt joints, going around the insulation 1m at a time. The material is supplied 1m wide, so this is achieved by cutting off the required length to go once around the pipe plus 50mm to overlap at the seam. This is then secured with welding agent. You should also allow an 80mm overlap for the butt joint. For more installation information you can visit Plysolene's Website Here:

We plan to do more of these style of blogs - if you have any requests for our next entry drop us an e-mail at:


Popular posts from this blog

The Beginners Guide to Pipe Insulation: Flexible Foams

Next up in the series we are doing on pipe insulation is "flexible foams"; a category that includes polyethylene and expanded nitrile rubber.

Polyethylene Pipe Insulation
Climaflex pipe insulation is the UK's leading brand for polyethylene pipe insulation. This is the grey foam that most people are familiar with, the kind you would traditionally find in garden centres for example. Polyethylene is the cheapest, widely available product in the market. People very often wrongly assume cheap means poor quality, this is not the case with a brand such as Climaflex. It has a thermal conductivity of 0.034 W/m.K at 0°C which is broadly equal to that of any other flexible foam, and it also has a much higher "μ factor" than other foams, making it more resistant to moisture ingress. These facotrs make it ideal for use around the home, being easy to work with and providing good insulation. 
The material can be purchased in 1m and 2m lengths, and is available in wall thicknesse…

The Beginners Guide To Pipe Insulation: Getting to grip with the basics

Our Beginners Guide series of blogs will look at the common areas of pipe insulation lagging that you will want to look at when choosing your product. This guide will be of most interest to the DIY installers, but some of our later guides will cover more complex products and areas of application.

One of the things we get asked about a lot is what the dimensions quoted for pipe insulation actually mean. You will always see three measurements quoted when describing pipe insulation; Wall Thickness, Bore Size and Length.

In the below diagram, A is the "Bore" and B is the "Wall".

Wall thickness is very simply how much insulation you have; so for example if you have 13mm Wall pipe insulation, then that means you have 13mm of insulation on either side of your pipe. This thickness is very often one of the most important part of your decision; too thin and you might not get the results you are looking for but too thick and it might not fit between your pipe and the wall.


Frost protection for domestic pipes

With the cold weather approaching we thought it would be a good idea to touch on how best to protect your pipes from frost this winter.

When dealing with frost protection on pipes inside a building your aim with insulating them is to delay the onset of freezing for as long as possible; it is not possible to guarantee a pipe will not freeze by insulation alone. The better the insulation, and the thicker the insulation, the longer you will give yourself. Under normal circumstances you aim to give yourself about 8-10 hours protection against sub zero temperatures. With pipes inside a home this is usually long enough to be sure the pipes will not freeze.

Ice formation inside the pipes will lead to an increase in pressure. As the water tries to flow this pressure will increase, and eventually will lead to the pipes bursting. A burst pipe can cause a lot of problems, not least of which is a lot of damage to your property and a lot of expense incurred.

Water regulations state that all water …