Loft Floor Insulation

What is loft floor insulation?

Loft floor insulation involves insulating the timber floor of a loft or attic space. This type of insulation is commonly installed when the loft is not used as a living area but is intended to prevent heat from escaping through the roof. By insulating the loft floor, more heat is retained in the living spaces below, resulting in lower energy bills and a more comfortable indoor environment. Pluimers Insulation uses a specially developed mineral glass wool for this application or a bio-based insulation material called Greenfloc Cellulose. One of the biggest advantages of loft floor insulation is that it is a relatively simple and cost-effective way to save energy when the loft is not used as a living or sleeping area.

How is loft floor insulation installed?

Loft floor insulation involves insulating the timber floor of a loft or attic space. This type of insulation is commonly installed when the loft is not used as a living area but is intended to prevent heat from escaping through the roof. By insulating the loft floor, more heat is retained in the living spaces below, resulting in lower energy bills and a more comfortable indoor environment. This form of insulation is particularly suitable when the loft floor is easily accessible and the loft is empty. Small holes are drilled between the joists, allowing the cavity between the floor below and the loft floor to be filled with insulation. Once the insulation has been installed, the holes are neatly sealed with cork plugs.

Which materials are used for loft floor insulation?

A timber frame is a construction method in which a building is built using a framework of timber beams. This framework forms the structural support of the building and is often combined with insulation materials such as glass wool to improve energy efficiency and thermal performance. Supafil Timber Frame or Supafil Loft glass wool is commonly installed between the timber joists to provide excellent thermal insulation. Glass wool is a widely used insulation material because of its outstanding insulating properties, affordability, ease of installation, non-combustible characteristics and excellent sound-insulating performance.

In addition to glass wool, Pluimers Insulation also offers Greenfloc Cellulose, a bio-based insulation material that is not only a sustainable choice but also financially attractive thanks to additional government grants. Greenfloc cellulose insulation is made from recycled cellulose fibres, such as recycled newspaper, and is treated with mineral salts to provide fire resistance, protection against pests and mould, and excellent moisture-regulating properties.

Grants for loft floor insulation

Several grants and funding schemes are available in the Netherlands to help reduce the cost of loft floor insulation. These include national government grants as well as local schemes offered by municipalities and provinces.

• 1. ISDE – Investment Grant for Sustainable Energy and Energy Savings (ISDE)
  The Investment Grant for Sustainable Energy and Energy Savings (ISDE) is the main national grant scheme for improving the energy efficiency of existing homes, including loft floor insulation. For 2026, the scheme offers the following:
  • Conditions: You must install one or two insulation measures (for example, cavity wall insulation and loft floor insulation), or combine one insulation measure with the installation of a heat pump, solar water heater or connection to a district heating network. The insulation must be installed by a certified contractor or insulation company. The loft floor insulation must also meet minimum technical requirements, including a minimum thermal resistance (Rd value).
  • Grant amount: The grant ranges from €4 to €8 per square metre for loft floor insulation. The exact amount depends on the achieved Rd value, the type of property and the number of measures installed.
  • Application: The grant can be applied for through the website of the Netherlands Enterprise Agency (RVO).
• 2. Local grants from municipalities or provinces
  In addition to the national ISDE grant, some municipalities and provinces also offer their own insulation grants, including funding for loft floor insulation. The conditions, reimbursement amounts and availability vary by region.
  • Conditions: Requirements differ depending on the municipality or province. They often relate to the insulation material used, the required Rd value and who carries out the insulation work.
  • Application: For information about local grants, consult the website of your municipality or province, or use the Dutch energy grant guide provided by Milieu Centraal.
• 3. Reduced VAT rate on labour
  The Dutch government offers a reduced VAT rate of 9% on labour costs for insulating homes that are more than two years old. This applies to all types of insulation, including loft floor insulation.

Does loft floor insulation improve your energy label?

Loft floor insulation can have a significant positive impact on a property’s energy label. An energy label indicates how energy-efficient a home is, and improved insulation reduces the amount of energy required for heating and cooling. As a result, installing loft floor insulation can help achieve a better, more energy-efficient energy label.

How much does loft floor insulation cost?

The cost of loft floor insulation depends on the insulation material, the thickness of the insulation layer and the size of the loft floor. When the insulation is installed by a certified insulation company, you may be eligible for government grants. Loft floor insulation can also deliver substantial savings on your energy bills. Depending on the size of your home and the level of insulation, you could save between €200 and €400 per year* on energy costs. This means that the investment can typically be recovered within 5 to 10 years.
*Source: Milieu Centraal

Loft floor insulation or roof insulation?

The choice between loft floor insulation and roof insulation depends on how your loft is used. The specific characteristics of your property also play an important role. Both insulation methods are highly effective, but they offer different advantages depending on your situation.

• Loft floor insulation: This is an excellent option if the loft is not used as a living or sleeping area and you only want to insulate the heated rooms below. Loft floor insulation prevents heat from escaping into the loft, helping to keep your living spaces warmer. It is generally more affordable than roof insulation, both in terms of materials and installation costs. It is also quicker and easier to install, especially when the loft is easily accessible. If the loft does not need to be heated, loft floor insulation is usually the most practical and cost-effective solution.
• Roof insulation: One disadvantage of loft floor insulation compared with insulating the pitched roof is that, if the loft is converted into a living space at a later stage, the roof will still need to be insulated to provide a comfortable indoor climate. If the loft is heated or intended for use as a living area, roof insulation is the more effective option.

Disclaimer

This page was last updated on 20 April 2026. We make every effort to ensure that the information on this page is accurate and up to date. If you notice anything that is incorrect, please let us know. No rights can be derived from the content of this page.