We stock a wide variety of insulation slabs, which are otherwise known as insulation batts. On our website, we only sell insulation slabs from top brands such as Rockwool and Knauf. Insulating slabs are common in construction for enhancing energy efficiency. These slabs are typically crafted from materials like fiberglass or mineral wool. They work by reducing heat transfer through various structural components such as walls, roofs, and floors. Below you can find our full slab product range at our lowest possible price.

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11% OFF
Knauf Dritherm 32 Ultimate Slab
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Knauf Dritherm 32 100mm Ultimate Cavity Slab (1200mm x 455mm) – 3.27m2 pack

Original price was: £36.42.Current price is: £32.33. ex VAT
17% OFF
Knauf Dritherm 37 Cavity Slabs
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Knauf Dritherm 37 100mm Standard Cavity Slab (1200mm x 455mm) – 163.75m2 pack

Original price was: £961.93.Current price is: £799.00. ex VAT
21% OFF
Rockwool RW6 Slabs
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Rockwool 100mm RWA45 Acoustic Insulation Slab (1200 x 600mm) – 2.88m2 pack

Original price was: £28.50.Current price is: £22.49. ex VAT
Rockwool Flexi Slab
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ROCKWOOL Flexi – 1200 x 400 x 100mm – 86.4m2 pallet

£799.00 ex VAT
Rockwool Flexi Slab
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ROCKWOOL Flexi Slab – 1200 x 600 x 100mm – 4.32m2 pack

£38.50 ex VAT
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Knauf Rocksilk RS45 Insulation Slab – 100mm (1200 x 600mm) – 43.2m2 pallet

£369.00 ex VAT
Rockwool Flexi Slab
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ROCKWOOL Flexi Slab – 1200 x 600 x 140mm – 46.08m2 pallet

£585.00 ex VAT
Rockwool RW6 Slabs
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Rockwool RW3 50mm Acoustic Insulation Slab (1200 x 600mm) – 5.76m2 pack

£35.99 ex VAT
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Knauf Rocksilk RS45 Insulation Slab – 50mm (1200 x 600mm) – 86.4m2 pallet

£355.00 ex VAT
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Knauf Rocksilk RS45 Insulation Slab – 60mm (1200 x 600mm) – 69.12m2 pallet

£349.99 ex VAT
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Knauf Rocksilk RS45 Insulation Slab – 75mm (1200 x 600mm) – 51.84m2 pallet

£325.00 ex VAT
Rockwool Flexi Slab
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ROCKWOOL Flexi – 1200 x 400 x 140mm – 46.08m2 pallet

£599.00 ex VAT

What are insulation slabs?

Insulation slabs are slabs made from different materials, each with unique properties. Fiberglass and mineral wool are the most common types. They are easy to install. Cavity slabs can be easily fit neatly into wall cavities, lofts, and other spaces. The choice of thickness and material depends on desired insulation levels (measured by R-value) and local climate conditions. We always suggest you speak to an architect or building professional before purchasing insulation batts. They should be able to consult you on the best suited product for your project.

Some insulation slabs, like mineral wool, possess inherent fire resistance, making them suitable for fire-prone areas. In addition to this, some slabs excel at sound absorption, reducing noise transmission within walls and ceilings. Most insulation slabs that we sell incorporate recycled content or environmentally friendly manufacturing processes.

Furthermore, some batts can be equipped with vapour barriers or may require the installation of separate barriers to prevent moisture infiltration, a crucial aspect in certain applications.

Insulation slabs are a versatile and cost-effective way to enhance energy efficiency and comfort in both new and existing structures. Properly installed, they help maintain consistent indoor temperatures, reduce energy consumption, and create more comfortable living and working spaces.

Insulation Batts

Each insulation slab offers different sizes, thicknesses, and densities, providing an effective solution for any residential or commercial property including flats, offices, hospitals, shopping centres and schools.

The slabs we sell are available in lengths of 1200mm by either 400mm, 455mm, or 600mm among other sizes. The thermal conductivity of the insulation slabs ranges between 0.032W/mK and 0.038W/mK. The insulation slabs are made up of glass mineral wool, stone wool, and rock mineral wool. The insulation slab materials are extremely durable and long last lasting.

Insulation slabs create a more temperature-controlled environment keeping your property warm in the winter and cool in the summer. By reducing the heat levels escaping the property, insulation slabs can reduce energy bills and have a positive effect on the fight against climate change.

Insulation slab benefits:

  • Lightweight and easy to transport
  • Easy to handle and install
  • Made up of recycled materials
  • Excellent thermal and acoustic properties
  • Improves the properties thermal conductivity
  • Energy Efficient
  • Extremely durable
  • Ensures a perfect fit between insulation and framework
  • Designed to prevents gaps in the insulation
  • More comfortable living and working spaces
  • Odourless, non-hygroscopic, rot proof, do not sustain vermin and will not encourage the growth of fungi, mould, or bacteria
  • Cheaper energy bills
  • Helps comply with applicable regulations
  • Reducing greenhouse gas emissions

Cheap Insulation Slabs

You can find cheap insulation slabs available to buy on our website. We take pride in offering cheap insulation slabs by top brands. Our motto is top brands at trade prices, which is exactly what we deliver. We have a variety of slabs available in many sizes and thicknesses.

When it comes to insulating a property, using insulation slabs is a cost effective way to provide insulation whilst being cost effective.

How to install insulation slabs

Measure the spaces within the frame rafter or joist where you will be applying the insulation. Note that not all sizes of the spacings within the frame will be consistent, particularly within older structures. Each insulation slab should be measured and cut to specifically fit each section of the frame.

Use an insulation saw, or sharp knife with a serrated blade, to cut the insulation to size if required. Do not overcut the insulation. Allow an extra 10mm on both dimensions (width and length) of the insulation, over and above the aperture dimensions.

The density and dimensional stability of mineral wool allows tight friction to fit. Insulation batts will not require pinning or fixings unless specifically stated otherwise. To install, simply push the insulation into one side of the structure and let the insulation go so it tightly fits into the other side of the structure and holds in place. Ensure there are no visible gaps, as this will have effects on the thermal performance.

Continue until the frame is full. Off cuts can be kept and used to fill smaller gaps. The project can be completed with the next steps depending on the method and area of insulation.

Insulation Slab FAQs

Are insulation slabs / batts better than rolls?

Batts are pieces of blanket insulation that are pre-cut to manageable sizes (15-24 inches wide by 48 or 93 inches long), while rolls are strips of insulation similar to batts in width but much longer (25, 32 or 48 feet, for example). Both types of insulation have the same quality as the other however depending on your project one product may be easier to handle and install than the other. For example, when insulating a loft, the rafters can be extremely long. Instead of installing lots of slabs, a roll is a much easier option and more time-effective option. If you’re insulating a pitched roof or upright wall, a rigid insulation slab is much easier to work with compared to a loft roll. This is because the insulation won’t sag or compress, so you’ll get the maximum performance in energy efficiency.

What are insulation slabs?

Insulation slab is also known as insulation batt. It's manufactured from glass wool and mineral wool, but instead of being formed into rolls (which is the most frequent type of insulation), it's made into rigid slabs and for easier use in upright positions and an easier method of application in areas such as walls and roofs.

Can you cut insulation slabs?

Insulation slabs can be cut by using a sharp knife. Simply ensure the slab is pulled tight and simply cut through the wool slab.

What thicknesses do insulation slabs come in?

Insulation slabs are available in thicknesses of 25mm, 30mm, 40mm, 50mm, 60mm, 65mm, 70mm, 75mm, 85mm, 90mm, 100mm, 120mm, 125mm, 140mm, 150mm, and 180mm depending on the chosen brand and product.

How many insulation batts do I need?

To determine the amount of insulation needed, start by measuring the height and length of each of your room walls. Multiply the wall's length by the wall's height and don't forget to write down the spacing and depth of the studs so you can then determine what type of insulation and thickness will be purchased.

Is it easy to install insulation slabs / batts?

Simply, yes. Insulation slabs are lightweight and more rigid than rolls. They are also delivered in tightly compressed packages making moving the product around and between different floor levels within the property is easier. As the slabs have a slight hold and flex in their form, fitting them into areas such as pitched roofs and walls is made simple as they are easy to fit between rafters. As the slabs are a good size to handle, it also means it is more manageable if working alone.