I'm sure you're aware that you can't fill, or 'top up' a cavity that's already been insulated, it can void your insulation guarantee provided by CIGA!
As long as the insulation within your cavity wall isn't damaged, then it can be topped up.
The insulation can certainly be reused, and providing enough care taken in removing the wall and cleaning the bricks/blocks off then they can be reused also(unless rendered, then you're stuffed).
This is another symptom of your cavity wall insulation's deteriorating health. Your boiler and radiators are working overtime to try and warm your house up, the heat wants to escape, and your insulation is allowing it! If your insulation can't even hold itself up, then there's no chance of it holding your heat in.
Retrofitting insulation into a cavity wall is adding layers to cover up empty spaces which are creating heating inefficiencies. An installer will insert foam or place insulation batts inside the wall during a retrofit.
As a general guideline, it's advisable to install double layers of thermal insulation throughout your house. Nevertheless, this may not be feasible in all areas due to space limitations. Typically, it's not practical to add two layers of insulation within the walls of your home.
There's no reason that it should break down and degrade into anything else, but if alterations are carried out to the building and the cavity wall insulation is allowed to come out of the cavity, then it will need topping up and some of it will need replacing.
Borescope Inspection
A qualified professional can use a borescope to inspect the cavity walls of your property. This will help determine whether insulation has been installed and whether the insulation remains in a good condition.
You can blow spray foam or cellulose into the walls from outside. Just cut a 1 inch to 2-inch hole between the studs at the top of the wall and then spray the insulation into the hole using a hose. Replace the cutouts, fill using wood filler and then sand smooth and paint to restore your siding.
Cavity wall insulation typically lasts between 20 and 100 years, and many insulation manufacturers offer a 25-year warranty on their materials. If your home was built after the 1920s when building regulations changed, then it likely has cavity walls instead of solid walls.
One of the main reasons as to why people decide to have their cavity wall insulation removed is because their property isn't suitable for it. For instance, if your property is often subject to wind-driven rain, then it is not recommended that a cavity wall is in place.
If you removed your cavity wall insulation due to poor installation or the use of dangerous urea-formaldehyde foam, then you can install new cavity wall insulation into your walls.
Does Insulation Make Your House Hotter In Summer? Insulation only slows down the transfer of heat from the outside to the inside, or vice versa, and doesn't directly heat things up or cool things down.
A cavity wall inspection can cost anywhere from £150 - £300, but some insulation companies provide free inspections with their cavity wall insulation packages.
Check Your Wall Insulation Level
Remove the outlet cover and shine a flashlight into the crack around the outlet box. You should be able to see if there is insulation in the wall and possibly how thick it is. Pull out a small amount of insulation if needed to help determine the type of insulation.
Cavity wall insulation can significantly improve energy efficiency in homes. However, if not installed correctly, it can lead to damp and mould issues. This post explores how past government schemes failed to address ventilation, leading to problems, and how new standards like GBIS and ECO4 ensure homes are protected.
Properties without a DPC, or where the DPC is too low (typically less than 125mm from the ground) and a French drain has not been installed. Some properties with raked mortar joints. Properties with a cavity wall under 50mm or over 150mm. Properties that have significant rubble or mortar ingress in the cavity.
The costs can vary depending on the factors mentioned above, but typically you might expect the following price ranges for different property types: 2 Bed Semi Detached: €1,600 – €1,900. 3 Bed Semi Detached: €1,900 – €2,200.
Two options are available for non-cavity walls: external insulation (around £12,000) and internal insulation (about £7,500). While expensive, government schemes like the Great British Insulation and ECO4 offer grants to help low-income households improve their homes' energy efficiency.
Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests. However, if the insulation is in decent shape and just needs a boost, adding a new layer on top can be a cost-effective option.
Most manufacturers offer a 25-year warranty, but the typical lifespan of cavity wall insulation is between 20-100 years. When installed correctly, cavity wall insulation is made to last the lifespan of your property. Unless damage occurs, all cavity wall insulation should last for up to a century.