Disadvantages of Internal wall insulation
Internal wall insulation also comes with additional risks and limitations over External wall insulation. For one it is less effective than External wall insulation and does not offer the same protective qualities. Internal wall insulation can make securing things to walls difficult. Stud walls are capable of holding heaving fittings, but if you have used insulation boards, the fittings need to be able to penetrate through them, then into the wall behind.
As discussed above this method also reduces the size of your room. The thicker you insulate your home the smaller your rooms will become. This means you are limited in the extent you can insulate your home.
Using Internal wall insulation means your home is far more likely to be affected with damp problems. Wet rot and mould can build up quickly on the inside of the masonry (the face that the insulation is fixed to) This can create hazardous spores, which will be breathed in by the occupants, and has the potential to create, or exacerbate existing health problems.
Another major concern when dealing with Internal wall insulation, is that a sufficient amount of warmth will not pass through the insulation and into the dwelling, (which normally keeps your walls dry) this means your walls will become damp and water ingress can turn to frost and damage your brick work, a process known as 'freeze thaw damage'.
Disadvantages of External wall insulation
There are few reasons against External wall insulation especially when compared to Internal wall insulation. Some of the reasons may be purely aesthetic, for example if you are fond of your brick work. This is because by externally insulating your home, you are covering the outside of your house with insulation materials, that will need rendering to create a polished and protective Finnish.
If you live in a flat this may also not be a realistic option, as the insulation would not be effective without also insulating the rest of the block. This is often not possible so in this instance you may turn to Internal wall insulation.
In some cases you may also need to be granted planning permission from your local council, to have your home externally insulated, so in this case you may also need to consider Internal wall insulation. In most cases we would recommend External wall insulation unless you are included in the above examples.
What Insulation Materials can be used for External wall insulation?
there are a lot of suitable materials for this procedure, so you will not feel limited for choice! You can choose between EPS, Kingspan, phenolic resin, wood-fibre, cork and mineral wool. You may decide to use
EPS (expanded polystyrene) as this is a popular option, and is one of the most cost effective materials.
External wall insulation must abide by strict
building regulations, which will have an affect on the material you choose. Solid wall insulation needs to have a U-value of 0.30 watts/m2k. The down side of EPS is that it requires a thicker amount of this material to achieve the same thermal performance/ U-value compared to Kingspan.
Mineral wool may be your preferred choice because by nature Mineral wool is moisture-resistant, and it is able to keep its insulating properties even when wet. Mineral wool is also good at blocking sound so means your building will have less acoustic invasion.
One of the best advantages of this material is its heat-resistant qualities- It will not burn until the temperature goes above 1000°C. Just ensure if you chose Mineral wool that you do not use an Acrylic render to Finnish, due to its lack of breath-ability, compared to the Mineral wool which will defeat the purpose of using Mineral wool in the first place.
Wood-fibre is a fantastic option as it is the most breathable, and natural insulation material, however this system is very pricey compared to the EPS system.
