Insulation in the spotlight

Buy Insulation Online has always strived to bring you the best quality insulation products at the best possible rates. We try to make your online insulation shopping experience as simple as possible. 

In this article, we will discuss some of the most popular insulation materials online at the moment.

Rockwool RWA45 Insulation Slabs: 

These insulation batts from Rockwool have actually been one of our best sellers for a while now. Their flexible application and insulation effectiveness have actually made this a buy insulation online favourite.Rockwool RWA 45 Insulation Slabs

RWA45 is well understood for not just its exceptional thermal insulation but likewise its acoustic insulation in residential or commercial properties. It is extremely fire resistant as it is non-combustible, making your house or facility that bit more secure from fire.

Make use of this as insulation in walls and you are making a sensible decision. As soon as installed RWA45 will enhance the convenience of your life in more methods than one.

With a K-value of 0.035 W/mK and a high density, RWA45 adds mass to the wall construction, hence soundproofing them. They are likewise made use of as roof insulation, in between rafters, insulation in loft floorings, plus in lots of other applications. It is an extremely flexible item.

RWA45 does not release hazardous glass fibres or gases into the air as it is made from rock mineral wool which is firmly bonded together with glue adhesive. They are durable, and their efficiency stays untouched by time for example they do not slump in the wall as would wood fibre cellulose insulation.

Rockwool insulation resists water, which signifies moisture-related issues like moulds, do not tend to be a concern with this item.

When it comes to insulation products, RWA45 is up there with the best products on the market.

Isover Clim Pipe Insulation: 

Buy Insulation online has members of our team who have years of experience as insulation engineers. The consensus is that Isover sections are the fastest pipe insulation to install on the market.

In our glasswool pipe insulation section, Isover clim pipe is the most cost-effective of all the mineral wool pipe lagging you can get in our opinion. This line of fibreglass pipe insulation from Saint-Gobain effectively protects pipes from heat loss and heat gain, depending on the application. They come in 1.2m lengths and are versatile and easy to install with self seal strips as standard. 

They can insulate pipes with service temperatures as high as 500°C. Along with being an effective thermal insulation solution, Isover clim pipe lagging also acts as acoustic pipe insulation. 

Fibreglass pipe insulation can reduce the operational sound in soil pipes for example, as it inhibits the travelling of sound waves by bouncing them around inside the air pockets between the glass wool fibres, thereby trapping the sound inside.

Made with 70% recycled glass, it has better environmental credentials than others such as Kingspan pipe insulation which isn’t made from any recycled material, although it does have better thermal conductivity values.

Isover clim pipe lagging can be used to insulate pipework located outside and inside a building. 

For external application, appropriate pipe insulation cladding must be used. Glasswool pipe insulation is non-combustible and helps meet building regulations.

Jablite Floor Insulation Boards:

EPS insulation from Jablite stands third on our bestseller list. Made in the UK, Jablite EPS insulation is best used to insulate floors, however, it also works well on roofs and walls. 

EPS boards are specially designed to keep the heat in and cold out. They are not recommended for acoustic insulation applications.

These lightweight insulation boards can be easily cut to size and installed between floor joists, walls or roofs. 

Made with polystyrene, EPS insulation boards offer excellent thermal performance over a range of temperatures. 


Dritherm insulation by Knauf - Cavity wall Insulation

Dritherm 32 and Dritherm 37 cavity wall batts by Knauf insulation are best used to insulate cavity walls in residential developments but it's also fine to use in non-residential construction as well. 

They have been on the market for many years and have proven to be excellent insulators for cavity walls time and time again. 

The difference between Dritherm 37 and 32 is the thermal conductivity. Basically, Dritherm 32 has a thermal conductivity of 0.032 W/mK whilst Dritherm 37 is 0.037 W/mK, making the 32 variant the better insulation of the two, albeit not by a huge margin. 

They are A1 (non-combustible) rating on the Euroclass scale, making them a great choice to use as insulation in cavity walls.

The cavity batts fit between upright wall ties nicely and they exhibit outstanding thermal performance for use in external full-fill masonry cavity walls. 

They use an environmentally friendly bonding adhesive instead of formaldehyde bonding agents used in other brands. This means less possibility of toxic gasses being emitted into your home over time.

Knauf Loft Insulation 

If you are looking to insulate your loft with a top-quality product, then Knauf loft insulation is the way to go. Using Knauf loft insulation can prevent up to 25% heat loss in your home. 

This means you keep your indoor environment at a comfortable temperature, keep the heat in and save on the energy bills. These loft rolls by Knauf insulation can help you achieve this.

Knauf’s unique Ecose technology uses a bio-based adhesive to bind the fibreglass strands together, meaning they do not come off the insulation easily making it more comfortable to install. You can simply roll the loft insulation between and over joists for easy installation. 

The perforated rolls are partially cut to enable easy installation. Knauf loft insulation rolls are also useful for insulating timber floors and stud walls. 

With a K value of 0.044 W/mK, Knauf loft insulation is cost-effective and gives a good level of fire protection as it is A1 non-combustible rated.

Rockwool Pipe Insulation

Rockwool pipe insulation is used to insulate both external and internal pipework. Rockwool has a service temperature ranging from 0°C to 250°C, which makes it ideal to insulate both hot and cold water pipes. Rockwool Pipe Insulation

Rockwool pipe insulation is chemically inert so can be used with all types of pipework including copper and carbon steel. It is also the most suitable to use on steam or very hot temperature pipework which you can't say for other types of pipe insulation. Rockwool pipe lagging has a K value of 0.034 W/mK.

This reduces the need to re-heat water, resulting in more energy savings. It also protects pipework from freezing by keeping the freezing temperatures out. They are durable, chemically inert and dimensionally stable. 

Because it is foil-faced pipe insulation rather than unfaced plain Rockwool, the foil facing acts as a vapour barrier and protects the pipework from moisture and related issues. It also reflects radiant heat from outside, keeping the pipework contents cool if that's what's required. 

Isover Climcover Duct Insulation 

Isover Climcover duct wrap Saint-Gobain is probably the best selling duct insulation in the UK. It is used to wrap ducts to prevent heat loss or gain in a ducted ventilation system. 

The heating and ventilating (H&V) system in a building is a network of ducts that helps deliver heated or cooled air indoors. 

Isover Climcover is an 1800mm wide insulation roll that insulates all kinds of ductwork. It also provides effective sound insulation and is non-combustible. Isover Climcover Duct wrap is the most recommended duct insulation product by our experts and laggers in the industry.

It doesn't give off lots of fibres when being installed, making it a more comfortable experience for the installer, yet a mask is still recommended of course.

Duct wrap helps protects ductwork from condensation, sweating and other issues that could cause damage to other services and fixtures such as ceilings. 

We also have given you a very detailed explanation of the ductwork installation process in our blog which you can find here.


Celotex PIR Insulation

PIR insulation boards are known for their excellent thermal insulation and versatile applications, and Celotex boards are no different. 

At Buy Insulation online, we store Celotex boards in sizes ranging from 25mm - 150mm. Celotex GA4000 boards are the best sellers in our PIR insulation section. They are a high-performance version of PIR insulation, giving better thermal properties than standard Celotex boards.

With a K-value as low as 0.022 W/mK, Celotex boards help keep the heat inside, no matter where they are used. PIR is only surpassed in thermal conductivity values by phenolic board, a.k.a Kingspan Board

Phenolic board is only slightly better in the brand scheme of things but if you are looking to save space then phenolic board is the way to go, but they are considerably more expensive than Celotex boards so a cost / benefit analysis would be required to see if its worth the extra expense.

Celotex Boards are long-lasting, have good compression strength and are relatively easy to install. They are effective in reducing thermal bridging in any application. 

The low-emissivity foil facings in the PIR insulation, act as the moisture barrier and also prevent heat loss through radiation. 


Valve Covers / Flange Covers

We are one of the leading suppliers of valve covers in the UK. Valve insulation jackets as they are also known, are the fastest, most cost-effective way to insulate valves, flanges, boilers and tanks. 

Valve covers not only protect the valves from heat loss but also from dirt and other impurities that cause harm to the valves. Valve jackets are made to perfectly fit the valves in question, as they come with pull cords and velcro straps which ensure a snug fit.

Valve jackets are super easy to install. Unlike traditional insulation, a valve jacket can be easily removed without causing any harm to the valves or the insulation itself, which is usually ripped to pieces and cannot be used again, requiring fresh valve insulation to be applied. There is the added benefit of valve covers not releasing fibreglass insulation shards into the air when they are removed or reinstalled. 

Valve covers can help protect the valves from condensation, thus keeping slips and accidents at bay although it is advised that chilled water pipework valves are vapour sealed with foil face duct wrap or use nitrile rubber, although these may require a specialist insulation company to come and carry the works out unless you are competent enough to them yourself.

They also protect personnel working in plants from contact with hot temperatures, thus improving workplace safety. 

At Buy Insulation Online, we also make custom insulation jackets to fit tanks, boilers etc. If you need a site survey we would be more than happy to carry out a proper count and measurement of your insulation jacket requirements. 

We could then give you a supply and fit quote or supply only, depending on your preference and budget. Contact us here to request an insulation cover site survey. 

Take a look at some of our other articles about valve covers if you are interested to find out more.

Rocksilk RS45 - Knauf Insulation Boards

Made in the UK, RS45 are high performing mineral wool slabs from Knauf insulationKnauf RS45

Similar in scope to Rockwool RWA45, they are versatile in applications and very easy to install between joists of the floor, wall or ceiling. They more or less meet every specification, use and performance need that you can think of. 

The name RS45 is derived from the density on the rock wool insulation slabs. With their high density, the rocksilk insulation ensures effective soundproofing in all applications. 

They are non-combustible and water-resistant. Knauf’s unique eco-binder Ecose technology, which is used to make these insulation batts, ensures that the strands of the mineral wool are tightly bound and do not come free, making life more comfortable for the installer. 

With a K-value of 0.035 W/mK, Knauf insulation boards will help you keep the heat in and sound out. What a superb product!

Rockwool Flexi - Rockwool Slab

Yet another high performing product by Rockwool. 

Rockwool Flexi is a mineral wool insulation slab made with patented technology that enables easy and perfect friction fit between the insulation slab and its supporting framework. 

These mineral wool slabs are dual-purpose, meaning they are used as acoustic and thermal insulation with a unique flexible edge along one side, allowing them to ‘spring’ into tight corners where fingers cannot reach.

Rockwool Flexi is ideal to insulate walls, roofs, floors, internal partitions and linings. Rockwool Flexi is the perfect insulation solution for any building project. It is particularly suited for framed constructions such as stud walls. 

With K Values between 0.035 - 0.038 W/mK, Rockwool Flexi not only performs great as thermal insulation but also effectively as soundproof insulation.

Rockwool Flexi repels water, is non-hygroscopic and does not support the growth of moulds. It is also non-combustible and an environmentally friendly product. 

Kingspan Kooltherm Pipe Insulation

Kooltherm pipe insulation from Kingspan is probably the thinnest wall thickness pipe insulation on the commercial market. Kingspan pipe insulation comes in lengths of 1m and can be used to insulate both hot and cold water pipes. 

With a best in class K value of 0.025 W/m*K, kooltherm pipe insulation ensures a high level of thermal insulation from ambient temperatures. It is the best pipe insulation as far as protecting the pipe contents from heat loss/gain goes. It also has decent compressive strength and will crack rather than squash and spring back like glasswool or rockwool pipe insulation

Kingspan pipe lagging has been the go-to product among for pipe insulators for a while now and why not, phenolic lagging does the job and is cost-effective. The Kooltherm pipe insulation range is ideal to insulate all kinds of pipework and is popular on commercial projects. 

Phenolic pipe insulation is equipped with a foil face which along with the closed-cell structure of the phenolic material, effectively protects against moisture ingress and protects the pipework from moisture, condensation and sweating. 

Rocksilk RS60 by Knauf Insulation

Much like its counterpart, RS45, these mineral wool slabs by Knauf, insulate walls, floors, ceilings and more. With a K-value of 0.034 W/mK, RS60 is Knauf RS60great as dual use thermal insulation and acoustic insulation  They perfectly fit between the joists of the floor, walls and any partitioned framework. 

What is the difference between RS45 and RS60 you might ask? Well, the difference is in the density of the insulation. RS45 is 45 kg/m3 and RS60 is 60 kg/m3, naturally. 

Other than that they have similar thermal properties but RS60 is known for its exceptional soundproofing abilities. RS60 is much better as an acoustic insulation board than RS45, owing to its superior mass.

RS60 is water-resistant, which reduces the risk of the insulation being affected by moulds. 

The Euroclass A1 rating for the insulation batts means they are non-combustible and do not contribute to fire in any way and help resist fire from spreading. As far as insulation slabs go, you can do much worse than choosing RS60, especially for soundproof insulation.  

Polyfoam XPS Insulation

Polyfoam XPS insulation is made from extruded polystyrene. They are moisture-resistant unlike standard EPS insulation, which means you do not have to worry about the insulation being affected by moulds or losing its low thermal conductivity rating. 

Polyfoam is a UK brand and the XPS boards are made in their factory in Hartlepool, Northern England. 

The high compressive strength of XPS boards makes them ideal for floor insulation and other floor applications such as use with underfloor heating systems.

With a K-value as low as 0.033 W/mK, XPS insulation is also ideal to insulate basement walls and floors, swimming pool basins and perimeter insulation below DPC.

Polyfoam will last almost throughout the entire life cycle of the building, its that durable. You can find out more about XPS insulation in our previous article which we wrote extensively about the manufacturing process of extruded polystyrene and its uses.

Superglass loft insulation

The current building regulation requires you to insulate lofts to at least 270mm to prevent a quarter of heat loss through the roof without loft insulation. 

You can achieve 270mm at very reasonable prices yourself using Superglass loft insulation on a roll. Made with fibreglass in their factory in Scotland, Superglass loft insulation is the most cost-effective and easy way to help keep the heat indoors in the winter, and the heat outdoors in the summer. 

Made from a high percentage of recycled glass, you could argue that it's environmentally friendly and carbon positive, due to the fact it has given a new life to old materials and also will reduce the amount of carbon emitted by a household significantly over its lifespan.

It comes as insulation on a roll and can be simply laid in between the joists for the first 100mm insulation layer, and then for the 170mm layer, perpendicular to the joists and the first layer to achieve optimal thermal insulation for your loft. They also help in soundproofing roofs. 

Loft insulation rolls from Superglass are A1 (non-combustible) when tested to BS EN 13501-1 – the highest rating possible. 

They are easy to install, but it's not a nice job but one which will save you lots of money over the years in lower energy bills. Having said that, we do recommend you contact an insulation contractor if you are not a competent DIYer.

The loft rolls are breathable, which means they do not trap moisture in their fabric. This property of Superglass loft insulation ensures that moisture does not harm the wooden parts of the structure through rot and decay.

If you are looking for fibreglass loft insulation, then Superglass Multiroll is the best choice in our opinion.

Actis Hybris Multifoil Insulation Panels

An innovative multifoil product from Actis insulation, it is constructed using polyethene foams glued to layers of aluminium coated foils in a honeycomb fashion to make Actis Hybris. It is a great all in one product. It can resist all three forms of heat transfer, convection, conduction and radiant heat. They also have a built-in vapour barrier. 

It contains lots of low emissivity air-filled cavities, which ensure the high thermal performance of the Actis Hybris. It even can help with acoustic insulation to a certain extent, more than most other multifoils such as superfoil can achieve.

Actis Hybris can be used to insulate walls, pitched roofs and ceilings acting as in between rafter insulation

Unlike mineral wool insulation, Hybris does not release fibres into the air, so the air quality is not affected by the multifoil insulation

They are extremely lightweight panels, making them very easy and enjoyable to work with. Hybris will last longer than mineral wool insulation owing to its polyethylene makeup and are resistant to wind and moisture.

Whilst not as cheap as some other options, it's certainly a premium product with premium payback to the owner. If you are looking for a high-performance multifoil insulation, then Actis Hybris should be your choice.

K Flex Insulation - Self Seal Nitrile Rubber Pipe Insulation:

Nitrile rubber pipe insulation by K-Flex insulation is instantly recognisable to most plumbers. It is probably the easiest pipe insulation for a non-professional pipe lagger to fit.

It is known by a lot of different names in the industry. Armaflex lagging, Armaflex pipe insulation, Armacell pipe insulation, black pipe lagging etc. Whilst these terms are fine to use and are used interchangeably, there is a distinction between them.

Armaflex insulation is the manufacturer's name. Armacell is a brand name in the Armaflex pipe insulation line of products. Nitrile rubber is the actual material that Armaflex insulation is made out of.

K Flex is the manufacturer's name in the same way Armaflex is. It is made in Italy, which has a history of producing premium quality goods. Just think of Ferrari, Lamborgini, Pirelli, Gucci the list goes on. 

K Flex Nitrile Rubber comes in lengths of 2m and can be used to insulate all kinds of pipes, across projects. They have an in-built vapour barrier that ensures protection from rust and water ingress. 

Nitrile rubber is whats known as closed-cell insulation which is popular to use on chilled water applications based on the fact that it can effectively prevent water ingress and pipe condensation issues.

With a thermal Conductivity of 0.040 W/mK at 40°C nitrile rubber helps keep the heat in and protects pipes from freezing and condensation. 

K flex pipe lagging is lightweight and incredibly easy to install even for an amateur due to its self-seal application. That is, it has 2 adhesive strips along each edge, which when pressed together form a tight seal. No need for aluminium tape or duct tape. 

Simply cut the insulation to size and place it over the pipework, remove the strips and join the ends together. With self-seal pipe insulation, you can insulate the pipework yourself. Easy peasy!

It only needs nitrile rubber tape to put around the joints that butt up to each other to complete the install and perhaps some pipe identification bands too.

As far as pipe lagging goes, K flex nitrile rubber is the most cost-effective and easiest to install of all the pipe insulation we have for sale in our store.

Duct Tapes

As far as duct tapes are concerned, we stock the high performing KlasseCLOTH ™ S10 duct tape

Made from a high quality enhanced fabric, Klasse duct tapes are reliable and have actually been specifically created for the particular requirements of the glazing market or Google duct tape wart and it can be used for this as well. 

KlasseCLOTH ™ uses an exceptional experience in application and surface, improving use and sturdiness.

Mostly created for sealing double-glazed systems, these flexible duct tapes can likewise be utilized for heavy container packaging, basic upkeep, pipeline wrapping, carpet repairing, air-conditioning duct joints and other joint sealing.

They come in box quantities only, so we can keep the price as low as possible for you making these duct tapes affordable.

In Conclusion:

At Buy Insulation Online, we also store other high performing insulation materials that will make your home/building more energy efficient. What really sets us apart from our many competitors out there is:

  • We plant 1 tree per order, and protect 5 existing trees, making your purchase carbon positive for life. We are a part of Ecologi and One Tribe and you can find our company pages here.
  • Our experts are just a call away and you can also ask for any advice on insulation on our Facebook group All about Insulation. There is no obligation to buy, It's not a sales pitch, but we genuinely believe in sharing our knowledge.
  • We deliver for free in major cities in the UK. You can find more about our delivery policy here.


We look forward to helping you meet your insulation requirements and make your shopping experience smooth and hassle-free. You do not have to take our word for it. Check out our Trustpilot reviews and you will know.


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