Is cavity wall insulation safe?

Is cavity wall insulation safe?

Most cavity wall insulation is perfectly safe – but it can depend on the material used, and more often and important the quality of the workmanship. Modern retrofit cavity wall insulation methods should pose no threat to those living in the home, but if your walls were insulated decades ago, you may want to check what was used. Similarly, if your cavity walls were wrongly insulated, this could cause you problems such as damp, and poor air quality because of lack of air flow.

Urea formaldehyde foam insulation

In the 1970s. 80s and 90’s, there was a rush to insulate thousands of homes as quickly and cheaply as possible – and this saw the widespread use of formaldehyde foam insulation, sprayed into cavity walls. In some cases, it was an effective insulant, and it wasn’t until later that people noticed the issues it caused.

Once inside the cavity, this foam shrinks as it cures, leaving air gaps in the walls which encourage cold bridging. But urea formaldehyde has been blamed for more sinister problems too.

When urea formaldehyde decomposes over time, it creates chemical fumes. There is evidence that exposure to high levels of airborne formaldehyde can lead to respiratory problems and other health issues.

If you’re worried that your home may have been insulated with it, it’s best to get a professional to take a look. If you don’t have the paperwork, they will be able to check with a borescope inspection to see whether or not it’s this type of insulation, and can also measure the levels of formaldehyde in the air to see if they are potentially dangerous.

Urea formaldehyde (UF) foam 1.1 Insulating materials which give off formaldehyde fumes (either when used or later in normal use) may be used to insulate the cavity in a cavity wall where there is a continuous barrier which will minimise as far as practicable the passage of fumes to the occupiable parts.

Blown fibre insulation

Another material that was once commonly used to insulate cavity walls is fibre. This is injected into the cavity, where it settles and compacts. Although it has no health effects when fully sealed within the cavity, if it escapes through gaps it can be a bit of a nightmare. Although blown fibre insulation isn’t classed as hazardous, it is an irritant – if it escapes, it can really itch your eyes and skin.

Another issue is that fibre insulation has often been installed in properties where it was unsuitable, or it was rushed. Once rainwater gets into the cavity, it saturates the fibre. This water can then track across into internal walls and present as damp. Aside from wet fibre being absolutely no use as an insulator, damp and mould can have serious health implications.

If you think this is an issue in your property, it’s wise to take steps to protect your home, your family and your health, take the cavity wall insulation out and start again.

We can recommend people we trust to do this for you. Bear in mind that if you’re removing/exposing blown fibre insulation, you have a responsibility to make sure it doesn’t escape and cause problems for your neighbours!

New cavity wall insulation – Polystyrene Beads

If you’re installing cavity wall insulation, it’s worth opting for a modern insulating material with proven performance! EPS (expanded polystyrene beads) and polyurethane foam are the most commonly used these days, and with good reason. Neither have health implications, and they are waterproof, so should be as effective in decades’ time as they are now. Always ask for an explanation of the insulation material your installer is using if there’s anything you’re not sure about.

Polystyrene Beads when used with a bonding agent that holds the beads together as they settle inside the cavity seem to be the preferred product, but have only been installed in a small number of properties because of the extra costs, and contractors opted for the lower cost fibre material.

Those who had beads installed may have found them across their lawns, garages, inside kitchen cupboards, coming up their sinks, leaking through air vents, and so on. This gives an indication that the beads were not glued, and because of bead loss, gaps at the top of the internal walls will create cold spots and then lead into damp and mould.

Probably one of the easiest products to extract, depending on the property.

If you’re one of the 3 MILLION homes that is affected by damp and mould, cold spots, damp smells, leaking insulation or excessive condensation, or you think you might have foam insulation, partial fill, or any other problems, don’t leave it to get worse. Statute of Limitations Act gives you a set time from date of knowledge to bringing an action.

Contact Wall Cavity Claims today for free and impartial service from industry experts, panel solicitors, the countries’ leading Chartered Surveyors and industry recognised extractors and repairers.

Freephone:                        0800-8-654321

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