The Ultimate Guide to Insulation


If you are within the public sector and you are looking to reduce your organisation’s energy bills and become more environmentally friendly, then this guide is the resource for you. This guide will provide you with the knowledge and tools you need to insulate your organisation’s premises effectively.

To create an energy-efficient organisation it is important that proper insulation is installed within the premises, to make sure that heat loss is significantly reduced during cold winter months, and that heat gain is significantly reduced in hot summer months.

In this guide we will cover a range of topics including the different types of insulation, how to install it and how to keep it maintained. Whilst also helping you find ways to save money and lower your organisation’s carbon footprint.

Browse the guide at your own pace or open the dropdown menu to click the links to jump to the sections you need the most.

Section 1 – Importance of Insulation

Insulating your organisation’s premises can provide a comfortable, energy-efficient, and sustainable working environment. It is essential that organisations insulate their premises, as it can offer a wide range of benefits including:

Improved Energy Efficiency: Effectively insulating your premises will reduce heat transfer, preventing warm air from escaping in the winter and keeping cool air in during the summer. The insulation barrier helps to maintain a comfortable temperature indoors and reduces the reliance on traditional heating and cooling systems, increasing energy efficiency.

Reduced Energy Bills: Insulating your organisation’s premises will help to significantly lower an organisation’s energy costs as well-insulated premises require less energy to maintain a comfortable temperature. Making insulating your organisation’s premises a wise long-term investment.

Enhanced Comfort: It will minimise draughts, cold spots, and temperature fluctuations, creating a more comfortable working environment. Insulation can also decrease noise transmission, making a quieter indoor atmosphere that is more suitable for a working environment.

Environmental Impact: Through insulating your premises, you can reduce your organisation’s energy consumption, which will also lower your carbon emissions. Therefore, choosing to insulate your premises will help to contribute to a greener and more sustainable future.

Condensation Control: By creating a thermal barrier, insulation can help reduce condensation. Condensation can cause a range of issues including mould, mildew, and damage to property. Insulation minimises these risks, which will overall protect your premises and create a healthy working environment.

Section 2 – Types of Insulation

If you choose to insulate your organisation’s premises, it is important to understand that there are different types of insulation materials. Each of these materials has its own properties, advantages, and recommended applications. The most common materials are:

Fibreglass: This material is affordable, readily available, fire-resistant, and easy to install. It is made from fine glass fibres that traps air to create a thermal barrier. Fibre glass also significantly reduces the growth of both mildew and mould. This material is recommended to be installed in lofts/attics, walls, and floors. When installing it is important to wear protective clothing as it can cause skin irritation.

Cellulose: This material is made from recycled paper that has been treated to be fire-resistant. This type of insulation has excellent soundproofing qualities and creates a good thermal barrier. Many organisations are choosing this material as it is a more sustainable option. It can be either blown or densely packed into loft/attic space, walls, and hard to reach areas. If choosing this insulation type it is recommended that you hire a professional.

Spray Foam: Spray foam expands to fill gaps, meaning it has excellent sealing properties that creates an effective thermal barrier and prevents condensation issues. In many cases this material can also increase structural rigidity. Spray foam can be used to seal gaps in wall cavities and in the loft/attic. Often this type of insulation is a more expensive choice.

Rigid Foam: This material provides a significant thermal barrier and protects against moisture. This type of insulation can be used both outside and inside of the premises and can provide good insulation in areas of limited space. Usually it is used in foundations, exterior walls, and under-slab applications. Commonly this type of insulation is a more expensive choice.

Reflective: This insulation type uses reflective material, such as aluminium foil, to reflect heat away from the working space. It is lightweight and is easy to install, combined with other insulation materials it can enhance effectiveness. It is important to note that reflective insulation should not be used as insulation alone and must be combined with another insulating material.

When choosing the right insulation for you, consider factors such as the climate, building structure and your budget. To determine the right material for you, consult a professional.

Section 3 – Areas for Insulation

Walls: Insulating walls will help to prevent both heat loss and gain, increasing the buildings energy efficiency. Consider the wall type (e.g., exterior, interior, load bearing, partition, or masonry), local building regulations, and the desired U-value. Walls can be insulated through cavity wall insulation (filling the gaps with insulation material) or adding insulation to the exterior or interior of the wall.

Roofs: Adding roof insulation to your premises will minimise heat transfer and prevent ice dams from occurring. Consider the roof type (e.g., gable, flat, arched, or hipped), the climate conditions, and ventilation requirements. Roofs can be insulated between the rafters, by adding insulation boards above the roof deck, or by using spray foam for sealing.

Floors: Insulating your floors can prevent heat loss or gain between the different levels of your organisation’s premises. Consider the floor type (e.g., over a heated area, carpeted or uncarpeted) and local building regulations. Insulation can be placed between floor joists, installed on the underside of the floor, or on the subfloor.

Lofts/Attics: Insulating loft space is important as heat rises and can be lost. Consider the desired U-level, air sealing, and the ventilation requirements. Insulation can be blown in or can be densely packed between loft joists. Insulating around hatches and vents can also reduce heat loss and gain.

Basements/Cellars: Insulating cellars can prevent heat loss and reduce issues caused by moisture, by helping to control humidity. Insulate the cellar walls or floors and seal any gaps or cracks.

Doors and Windows: These tend to have their own insulating properties although their efficiency can be increased. Consider seals, weatherstripping, and double glazing. Draught stoppers, door sweeps, curtains, and blinds are also effective.

Section 4 – Insulation U-Value

In the UK the thermal performance of a building element is shown through its U-value. This shows the amount of heat loss per square metre per degree (Celsius) temperature difference.

The UK’s Building Regulations set the minimum U-value for different parts of a building, including the walls, roofs, floors, windows, and doors. The requirements are based on the construction type, specific location within the UK, the region’s climate, energy efficiency standards, and building regulations. Achieving higher U-values than the minimum requirement can result in better energy efficiency and thermal performance.

When considering insulation, it is recommended that you consult the Building Regulations, local building authorities, or a professional for the specific U-value requirements and recommendations.

Section 5 – Insulation Techniques

Air Sealing: Seal gaps, cracks, or openings before insulating to prevent air leakages. Use caulk or weatherstripping around windows or doors. Pay attention to junctions between different building materials.

Vapour Barriers: Vapour barriers are essential in areas with colder climates to control moisture and prevent condensation. They should be installed on the warmer side of the insulation to prevent moisture reaching the colder side. Make sure sealing is done properly and overlap if necessary.

Ventilation Considerations: Ventilation is important to maintain indoor air quality and control the levels of moisture. Install ventilation systems to ensure fresh air is circulated whilst retaining heat.

Avoiding Common Mistakes: Compressing insulation materials can reduce their effectiveness. Make sure cavities are filled properly to eliminate gaps or breaks in the thermal barrier. Always follow the manufacturer’s guidelines.

Loft Insulation: Ensure consistent coverage, lay insulation between and over ceiling joists to ensure optimal thermal performance. The recommended thickness for loft insulation is around 270mm thick. To maintain insulation avoid compressing the material used around the eaves.

Wall Insulation: Hire a professional to inject insulation into cavity walls. For a continuous insulation layer, obstructions must be properly cleared. For solid walls, consider exterior or interior insulation. For guidance seek expert advice.

Floor Insulation: Insulate floors that are above unheated spaces. Install the insulation material between floor joists and ensure proper coverage. For solid floors use insulation boards or rigid foam insulation.

Windows and Doors: Use draught proofing strips to increase energy efficiency, alternatively you can also apply sealant or weatherstripping, and install double or triple glazing. To reduce heat loss further consider insulated or thermal curtains.

Professional Assistance: Seek advice from a certified insulation professional or energy assessor if you are unsure about your insulation needs. They can provide tailored recommendations and can ensure that you are complying with the building regulations.

Section 6 – Energy Audit

Conducting an energy audit is a valuable way to improve your organisation’s energy efficiency, as it can identify areas of heat loss. An audit can help to pinpoint areas within your premises that is losing heat, such as through poorly insulated walls, roofs, or windows. By addressing these areas and improving their insulation properties you can increase your organisation’s energy efficiency and reduce your heating costs.

Energy audits can also help you to detect if there are any air leakages within your premises, such as through cracks, gaps, and openings. Identifying and sealing these areas will help to prevent draughts and heat loss. Which will ultimately lower your heat consumption.

Once you have completed an energy audit you will be able to prioritise any upgrades that need carrying out, based on their potential impact and cost effectiveness, as well as making informed decisions.

To carry out an audit you must:

  • Carry out a visual inspection, such as looking for leaks (draughts, gaps, cracks) around windows, doors, or electrical outlets. Check the insulation levels in the loft/attic, walls, and floors.
  • Use a thermal imaging camera or a smartphone app to detect temperature differences. This will help to identify areas of heat loss.
  • Hire a professional to carry out an air leakage test. To do this negative pressure needs to be created to identify air leaks.
  • Evaluate how efficient your appliances, lighting, and heating/cooling systems are. You may need to consider upgrading to more energy efficient models.
  • Ensure that you review your energy bills to identify areas of high consumption.

It is recommended that you hire a professional to carry out your energy audit. This is because they can provide a comprehensive assessment using suitable equipment alongside their expertise. Inspections will be carried out thoroughly, in order to find the precise areas within your premises that are causing air leaks and heat loss.

When looking for a professional, make sure that they are certified or affiliated with a recognised efficiency programme or organisation. Once they have caried out their audit they should supply you with a detailed report, with recommendations and guidance tailored to improving your organisation’s energy efficiency.

Section 7 – Insulation Cost and Budgeting

Insulation Costs

Material Costs: The price of the materials will vary depending on its type and quality. Fibreglass, cellulose, spray foam, and rigid foam tend to be the cheaper options, although this depends on the quality, amount, and thickness.

Installation Costs: Hiring a professional to install the insulation comes with additional costs. Prices can vary depending on the size, material type and complexity of the installation process. One of the most important aspects of hiring a reputable professional installer is that the job will be done correctly.

Potential Savings: In the long-term, insulation can provide significant energy savings, as it will reduce heating and cooling costs. The amount of savings will depend on the quality of the material, the size of your premises, and your organisation’s energy consumption patterns.

Budgeting Strategies and Cost-Effective Options

Prioritise: Identify areas of your premises that will benefit the most from insulation. Ensure that you focus on areas that suffer from significant heat loss first, such as the roof, walls, and windows.

Research: Research the different insulation types, their costs and thermal performance before making a decision. Compare prices and consider their long-term benefits.

Grants and Incentives: Research grants, incentives, or government schemes that could help to offset the costs of insulation installation.

Professional Installation: A DIY installation may be the cheaper option, however, many of the insulation materials require extra research, specific safety measures, or complex installation processes. It is recommended that a professional is hired, as they will already have the knowledge, skills, and experience required. A professional installer will work efficiently, reducing the disruption to your working day. Reputable insulation contractors may also provide warranties and guarantees.

Bulk Purchasing: If you are insulating a large area or multiple premises it may be best to make a bulk order, as contractors or suppliers may offer discounts.

Long-Term Perspective: Consider insulation as a long-term investment. Although upfront costs can be significant, the energy savings over time can lower energy costs in the future offsetting the initial expenses.

Section 8 – Insulation for Different Building Types

Schools and Educational Institutions

  • Fibreglass: Is often used to insulate classrooms and administrative areas.
  • Cellulose: Can be used within existing wall cavities and areas that require soundproofing.
  • Spray Foam: Used to insulate hard-to-reach areas and to create an airtight building envelope.

Government Offices, Administrative Buildings, and Municipal Buildings

  • Fibreglass: Provides thermal insulation for office buildings.
  • Mineral Wool: Is fire-resistant and is also used to soundproofing meeting rooms and offices.

Hospitals and Healthcare Facilities

  • Mineral Wool: Fire-resistant and is used for soundproofing consulting rooms and wards.
  • Polyisocyanurate (PIR) or Polyurethane (PUR) Board: Can provide insulation for operating theatres and patient rooms.

Museums and Cultural Centres

  • Spray Foam: Used to seal exhibition spaces to protect artefacts.
  • Rigid Board Insulation: Used in areas that require impact resistance, moisture buildup prevention, and controlled climate conditions.

Recreation Centres and Sports Facilities

  • Spray Foam: Provides effective insulation for gyms and swimming pool areas.
  • Fibreglass: Thermal insulation is provided for space used for recreation and exercise.

Police Stations and Law Enforcement Facilities

  • Fibreglass: Can be used to insulate offices and communal areas.
  • Cellulose: Used to soundproof interrogation rooms and detention areas.

Fire Stations

  • Mineral Wool: Is fire resistant and is often used in firefighter living quarters and training rooms.
  • Fibreglass: Provides administrative areas with thermal insulation.

Public Libraries

  • Cellulose: Effectively insulates walls and loft spaces.
  • Rigid Board Insulation: Can be used in temperature sensitive areas, such as for archives and special collections.
Section 9 – Insulation and Building Codes

Building Codes and Regulations

Building Regulations: The UK’s Building Regulations set the minimum standards for insulation for renovations and in new constructions. The UK Government provides specific guidance on thermal performance requirements, including the U-values for walls, floors, roofs, and windows.

Certifications and Standards

  • British Board of Agrément (BBA): This certification verifies the quality, compliance, and performance of insulation materials and products. This provides assurance to the builder, regulator, and the organisation.

Government, Local Authorities and Energy Suppliers

The UK Government, local authorities, and energy suppliers may offer incentives, rebates, or grants to give organisations financial support towards making energy efficient upgrades. These programs and schemes can vary by region, so it is advised that you check which of these are available for your organisation.

Section 10 – Maintenance and Upkeep

Regular Inspection

  • Periodic visual inspections should be conducted to check the insulation in accessible areas, such as in lofts and cellars. Check for damage, including tears, pest infestations, and compression.
  • Check the moisture levels that can compromise the effectiveness of the insulation, including water stains, mould growth, or dampness.

Addressing Damage or Wear

  • Promptly repair or replace any insulation that is damaged. Patching materials are available for minor tears or compressions. To restore the integrity if the insulation you can add additional insulation.
  • Check the insulation around pipes, ducts, and electrical outlets. These areas can be prone to damage or displacement.

Moisture Management

  • Any identified sources of moisture need to be addressed as they can degrade the performance of the insulation and cause mould growth. Plumbing leaks need to be fixed promptly and dehumidifiers can be used in damp areas.
  • To prevent moisture from entering the insulation layer, make sure vapour barrier techniques are in place.

Settling and Compression

  • Reposition or fluff up loose fill insulation to stop the reduction of effectiveness.
  • Make sure and check that rigid foam or batt insulation hasn’t sagged or shifted, especially in walls.

Air Sealing

  • The efficiency of insulation increases when it is combined with proper air sealing. Regularly check for gaps, cracks, or draughts around windows, doors, or electrical outlets. Use weatherstripping, caulk or sealant to address air leaks.

Professional Insulation Assessment

  • You can hire a professional insulation contractor to assess your insulation, especially for hard-to-reach areas. They will be able to tell you if there are any problems.
  • Professionals can also use thermal image and other techniques to identify issues, assess thermal performance, and recommend solutions.