Wall Insulation

Most of the heat lost from houses escape through the walls. Insulating these walls will slow down any warmth passing between them and will keep the warmth inside the home for longer while reducing the money you spend on heating.
Externals walls can usually be insulated either by applying high density insulation material internally, externally or both.
If you're unsure whether your walls have a cavity in them you can usually check by either looking at the pattern of bricks or by measuring the thickness of the walls next to a door or window.

Cavity Walls

A cavity wall is made up of two walls with a gap in between, known as the cavity.
Heat will always flow from a warm area to a cold one.
In winter, the colder it is outside; the heat from your home will escape into the outside. In this case then you may be heating the outside air, instead of just heating your home.
Insulating your cavity walls is a simple and effective way to reduce your heating bills – and have a warmer home.
Cavity wall insulation can cut your heating bills so much that it will pay for itself quickly. There is always a practical limitation to the width of a cavity in buildings. This limitation requires the thinnest possible insulation material to provide sufficient thermal resistance to allow cavity wall insulation to meet the building regulations.
The thermal resistance is proportional to the thickness of a layer of the construction and inversely proportional to its conductivity. A construction layer with a high thermal resistance (e.g. rock wool), is a good insulator; one with a low thermal resistance (e.g. concrete) is a bad insulator.

Internal Wall Insulation

The insulation of the internal surface of walls is an alternative to external wall insulation. Insulating these walls will slow down the rate at which heat is lost and keep the warmth inside the home for longer.
Insulated plasterboard enables internal wall insulation in one easy application without impacting on the interior space. This internal insulation is ideal for upgrading the thermal performance of existing buildings by insulating from the inside.
There are various ways to insulate internal walls; this is done by fitting rigid insulation boards to the wall, by building a stud wall filled in with insulation material such as mineral wool fibre, or by fitting a flexible thermal lining.
Rigid insulation boards come in a variety of materials and thicknesses and deliver the highest energy saving. Some have pre-attached plasterboard which makes the installation process more straightforward.
Insulate internal wall with Batten.
This is a good option if the original wall is rough and uneven, as in some stone properties. The battens are on the warm side of the insulation so cannot rot. Battens are fixed to the walls; insulation is fitted between them and then covered with plasterboard.
This also allows a much better vapour barrier, but it is essential to seal the room-facing surface of the insulation to stop water vapour getting into the back of the insulation or into the wall and causing damp.
Flexible Thermal liner is basically a thin material that is used to help maintain heat in a room and is glued to the wall using a special adhesive. It is made from wood fibres interwoven with durable textile fibres.
This gives you is a very strong, flexible material that when attached to the walls is said to increase the energy efficiency of the room in question. Moreover, as flexible linings tend to be no more than 10mm thick they can be a good option for rooms that have limited space.

External Wall Insulation

External wall insulation is an innovative solution for older homes which don’t have cavity walls. External wall insulation helps to make a property warmer, more weather-tight and a wide choice of colours and textures can enhance the appearance substantially.
External solid wall insulation involves adding a layer of insulating material to the outside walls of a building and coating this with a protective render or cladding. There are lots of options to create the finish that you want and these may even add value to your home.
External solid wall insulation, rather than internal, may be particularly suitable if you want to avoid any loss of space.
These solid wall properties need to be insulated with solid wall insulation which involves adding a layer of insulation to either the inside or outside wall. The purpose of insulating in this manner is to slow the movement of heat out through the walls thereby dramatically reducing heating demand.
The insulating process involves covering the original brickwork and therefore the process can significantly alter the appearance of the property.
When solid wall insulation is installed on the external walls of the home, it must be done to adhere to building regulations.
External wall insulation is a great way to protect against penetrating damp, creating a new weatherproof layer on the outside of the building, and slowing the movement of heat through the walls. Another advantage of solid wall insulation is that it will cause the temperature of the walls themselves to rise. This means if there is lots of water vapour in the air (from cooking or washing for example); this will no longer condense on these walls.