ISOLENA SilentWool Acoustic Underlay + Breathable Paper
£121.11 (inc. VAT £145.33)
ISOLENA ‘SilentFloor’ acoustic underlay is a roll of 3mm thick Sheepwool insulation + breathable paper, that cushions the impact between the finished surface (laminate, solid or semi-solid wooden floors) and the subfloor (concrete or OSB boards).
Available to order - Lead time variable.
Isolena acoustic underlay ( formerly known as Sheepwool SilentWool: Floor) is a roll of 3.5mm thick Sheep Wool Insulation, that cushions the impact between the finished surface (laminate, solid or semi-solid wooden floors) and the subfloor (concrete or OSB boards). The layer of wool removes the contact between these two hard surfaces by creating an intermediate layer which absorbs this vibration. Improves footfall noise by 50% . Improves the extent of impact sound up to 21 dB
SilentWool: Floor rolls are produced in 1m wide rolls and are 25m in length. (25m2 per roll). Fitted with pesticide-free tested wool protection Ionic Protect®; SilentFloor comes with a breathable paper to ensure that the product is easily installed, and the breathable paper also serves to protect the product once installed. Suitable for use with underfloor heating.
Dimensions 25m × 3m × 0.35 cm
Fitting Instructions
SilentWool: Floor is supplied in 1m width and 25m length rolls. The product should be stored flat on a dry surface. SilentWool: Floor can be used under solid timber floors, laminate floors, parquet floors and OSB/MDF boards. It can be installed upon joisted, raft and concrete floors as well as OSB/MDF boards. By design, SilentWool Floor will unroll with the paper layer on top. Install with the paper side facing up. Suitable for use with underfloor heating.
Preparation
The sub floor must be thoroughly clean and dry. When setting on a concrete floor, ensure surface is even and free from imperfections that may damage the floor being installed.
Installation
By design, SilentWool: Floor will unroll with the breathable paper on top (where fitted). At the walls, take edges of the insulation up the wall by 2cm to avoid sound bridging. Cut around any obstacles using the measuring tape and marking pen for accuracy. Side-by-side sheets should be joined with sticky tape and not overlapped to avoid an uneven finish. Install the floor as per manufacturer’s instructions. Return to the floor edges once complete and fold the insulation behind itself to further insulate from the walls.
FAQs
What is ISOLENA acoustic underlay insulation?
ISOLENA acoustic underlay is a high-density sheep wool insulation (100kg/m³) designed specifically for floor soundproofing and acoustic decoupling. It is made from 100% natural sheep’s wool, with no synthetic additives.
What is acoustic underlay insulation used for?
This product is designed for floor sound insulation, including:
• Acoustic underlay beneath flooring
• Subfloor insulation
• Timber floor upgrades
• Reducing impact sound between floors
It is ideal for improving acoustic comfort in both new build and retrofit projects.
How effective is ISOLENA acoustic underlay at reducing noise?
SOLENA acoustic underlay provides:
• Impact sound reduction of 21 dB
This helps significantly reduce footfall noise and sound transmission between floors.
What is dynamic stiffness and why is it important?
This product has a dynamic stiffness of 50.7 MN/m³
Lower dynamic stiffness improves:
• Impact sound reduction
• Acoustic decoupling between floor layers
Making it highly effective in acoustic floor systems.
Is ISOLENA acoustic underlay breathable?
Yes. It is fully breathable with:
• Vapour resistance factor µ = 1
This supports vapour-open construction and helps manage moisture.
Does sheep wool acoustic underlay regulate moisture?
Yes. Sheep wool naturally:
• Absorbs and releases moisture
• Helps regulate humidity
• Reduces condensation risk
This is particularly useful in timber floor constructions.
Is ISOLENA acoustic underlay safe to install?
Yes. It is:
• Non-irritating to handle
• Free from harmful chemicals
• Safe to install without specialist protective equipment
It is easy and pleasant to work with on site.
Is it resistant to mould and pests?
Yes. ISOLENA acoustic underlay offers:
• Mould growth rating: 0 (no growth)
• Insect resistance: Class 0
This ensures long-term durability and reliability.
What thickness is available?
ISOLENA acoustic underlay is typically supplied as:
• 3.5mm thickness rolls
• 1 metre width, 25 metre length
This makes it ideal for thin acoustic floor build-ups.
What is the fire performance?
The product achieves:
• Fire classification: C-s2, d0
Meeting standard requirements for insulation materials.
Is ISOLENA acoustic underlay environmentally friendly?
Yes. It is:
• Made from renewable sheep wool
• Fully recyclable
• Free from synthetic additives
A strong choice for sustainable construction projects.
How much moisture can sheep wool insulation absorb?
Sheep wool insulation can absorb up to 33% of its own weight in moisture without losing its thermal performance.
This helps regulate humidity within the building and reduces the risk of condensation.
How long does sheep wool insulation last?
Sheep wool insulation is extremely durable. While it carries a declared service life of 50 years, real-world performance is likely to exceed this considerably when installed within a well-designed, vapour-open building fabric.
Can sheep wool insulation be reused or recycled?
Yes. At end of life, sheep wool insulation can be:
• Reused if carefully removed
• Recycled into other wool-based products
• Composted and used as a natural fertiliser
• This supports a circular building approach.
How is sheep wool insulation produced?
The production process involves:
• Washing raw wool using water and natural processes
• Mechanically forming fibres without synthetic binders
• Using Ionic Protect® treatment for durability
This ensures a natural, low-impact manufacturing process.
Where does the sheep wool come from?
The wool used within ISOLENA brand products is sourced from European sheep farming, primarily as a by-product of agriculture.
This supports local supply chains and reduces environmental impact.