Cavity Insulation is key to reducing energy bills, making a comfortable home, and reducing the carbon footprint created by heating your property.
What Is Cavity Wall Insulation?
Cavity wall insulation fills the gap between two brick layers on your external and internal walls. It prevents your home from letting out all that heat, so it is an excellent way to insulate it. Most homes built after the 1920s have cavity walls; filling them can save the homeowner up to 35% in heat loss. This makes your home warmer in winter and cooler in summer and helps save on heating bills.
How Is Cavity Wall Insulation Installed?
Installation is easy. For external walls, just a couple of small holes are drilled. The insulation material is injected into the cavity—mineral wool, polystyrene beads, or foam, as you like. The holes are patched up, and the house is back as it was.
Steps:
- Assessment: A professional will assess the condition and suitability of your home for cavity wall insulation, which would include inspection of the external walls and examine if dampness or cracks is affecting the performance of the insulation.
- Drilling: Small holes are drilled at regular intervals into the mortar between the bricks to place entry and exit points for the insulation. The holes are 22 mm in width and should be as uniform as possible to ensure complete coverage within the wall.
- Insulation Injection: Pressurised injection into the cavity forces a chosen insulator to fill every area throughout the space. The tech will monitor flow to ensure no voids or weak spots remain in the cavity.
- Patching: The holes drilled for filling with insulation material are filled with cement to restore the appearance of the wall. The filler matches the mortar close enough that it does not drastically affect the look of the exterior side of your house.
Is My Home Suitable for Cavity Wall Insulation?
Not all homes can apply cavity wall insulation. You have to assess your home accordingly. Most homes built between 1920 and the present day have cavity walls, which qualify for this installation. Structures before these periods will normally be solid wall constructions that do not work well for cavity wall insulation but can use internal or external wall insulation techniques instead. However, the external walls must be in good order so that damp issues or cracks within them will not diminish the effectiveness of the insulation and may allow it to become damp – a serious problem!
What Materials Are Used for Insulation?
Several products are available for cavity wall insulation, each with its own benefits. Your choice will depend on factors including fire resistance and cost. Most installation companies can guide you through the available options based on your needs.
Types of insulation materials:
- Mineral wool: Fire-resistant mineral wool is one of the most popular or most sought-after fibre-based insulating materials made from mineral wool and therefore a good choice for fire-efficient homes. Other than the fire-resistant property, it can be manufactured in an effective state to reduce heat loss, and it can also be manufactured from recycled materials, so one adds up to an eco-friendly condition.
- Polystyrene beads are small, lightweight balls that can be easily pumped into any cavity. They lock onto one another inside the cavity, allowing them to create a quality insulating barrier. They are durable and resistant to moisture, thus making them a perfect choice for a home built in a damp climate.
- Urea-formaldehyde foam: This is one of the materials that were widely used for cavity wall insulation, though it is relatively out of use these days because of newer options in some other materials. It expands inside the cavity and acts as insulation; however, it is prone to degradation, making newer options preferable.
Will Insulating My Walls Cause Damp?
A very common question is whether cavity wall insulation generates damp problems. Properly installed cavity wall insulation should not cause damp; it can be regulated to limit condensation on internal walls when temperature is regulated. However, if dampness already exists within your home, it is essential to solve these first because insulation may worsen the situation. Walls must be free of cracks and other damage before installation.
How to avoid damp issues:
- Walls to be dry: Before you start with cavity wall insulation, ensure that your outer walls are dry.
- Proper Installation: It is essential always to hire a certified and experienced professional to carry out the installation.
- Ventilation: To control moisture inside the house, you should install a proper ventilation system, such as extractor fans and air bricks. This is especially necessary for items like toilets, bathrooms, or kitchens that generate moisture.
Can I Insulate a Listed Building?
For listed buildings or homes in conservation areas, you might need special permission to make any changes to the outer look of the building. Cavity wall insulation would then become one option; however, it is advisable to consult your local council about it first because, in some cases, internal insulation would be a better alternative.
Do I Need to Worry About Ventilation?
A healthy indoor environment calls for good ventilation. Cavity wall insulation minimises air movement across walls, therefore, existing ventilation systems in the house, such as air bricks or extractor fans, should be working; additional ventilation can be added while installing cavity wall insulation.
How Long Does the Installation Take?
Cavity wall insulation installation is normally fast and hassle-free. Most homes only take a few hours to install without interfering with your normal life activities. Larger homes take longer, but not typically more than one day. The work is performed from the exterior side, so you need not worry about any interior disruption or mess.
Extra FAQs to Consider:
- How long does cavity wall insulation last? Most cavity wall insulation materials typically maintain their effectiveness for 20 to 30 years or more, depending upon the standard of installation plus the materials used.
- Can I remove the cavity wall insulation? You may require removing cavity wall insulation if it has been fitted improperly or if your cavity wall insulation is causing damp issues. Where possible, seek a professional opinion before removing your cavity wall insulation, as the expert will be able to advise whether the removal is required or if repairs can resolve the problem.
- What happens if my home has partial insulation? Then it can be topped up to reach the current standard. A professional installer can assess the current level of insulation and identify how to fix it.
- How do I know if my insulation is working? You will find that immediately after installation, your home retains heat much better than before, especially during the coldest of seasons. If you are keen on knowing the effectiveness of your insulation, you could consider an energy efficiency test in the form of a thermal imaging scan, which would depict where all the heat was escaping from your home.
Protect Your Family from Cold
Cavity wall insulation could make your home even warmer without raising energy bills. When done correctly with proper planning, you can avoid the most common pitfalls related to dampness and ensure that your home remains energy efficient for decades.
Contact Cavitech on 01903 331 578 for full information about whether cavity wall installation is a good choice for your home.