This section is intended to give you an overview of all the different types of insulation, how they are installed (and the relative ease of doing so) as well as the approximate cost. Exact costing will depend however on the particulars of each property.

We provide all kinds insulation: Cavity, loft, floor and solid wall. If you would like further guidance on insulation, a quote or clarity on anything you have read on this page, then please contact us and give us a call on 01223852267.

  • Loft Insulation
  • Cavity Wall Insulation
  • Flat Roof Insulation
  • Internal Solid Wall Insulation
  • External Solid Wall Insulation
  • Floor Insulation
  • Draught Proofing
  • Heating System Insulation
  • Energy efficient glazing and external doors
  • The first concern for any property owner should be to conserve energy. That is, to keep the energy you have produced. UK properties are notoriously badly insulated and thus lose a lot of heat. This means that energy bills are higher than they should be. A typical house has the following Heat Loss areas:


    Loft Insulation:

    Possibly the cheapest and most effective method of insulation. Can cost as little as £50 per house. Not worth going over 270mm of insulation as this makes marginal difference. Products available on the market are numerous with manufacturers such as Jablite; Knauf; Rockwool and Saint Gobain.

    Estimated Cost £50-£250
    Estimated Annual Payback £100
    Estimated Payback Period 2 years


    Cavity Wall Insulation:

    Most homes built after 1920 have a cavity (or gap) between the inner and outer walls. Filling this cavity with special foam insulation can considerably decrease the amount of energy required to heat your home.

    Houses with cavity walls are generally built after 1932 (house pre-1932 typically have solid walls). If the brick configuration on your property looks like this:


    The alternative is that the solid brick wall will look like this:


    Once it has been ascertained that you do have a cavity wall, you must then determine whether it is filled or not! This should be done by a professional installer. Should you need the cavity filled, then a qualified installer must be used. An installer should be registered with the Cavity Insulation Guarantee Agency, which offers a 25 year warranty on works undertaken.

    Installation is done by drilling a small hole (about 25mm in diameter) in equal spaces through the external wall. The insulation foam is then pumped into these holes before they are filled and sealed. There is no mess and the holes, once filled, are hardly visible to the naked eye once completed.

    The costs are indicated below. The installation involves pumping insulating foam into the wall cavity:


    The entire process takes approximately one day to complete.

    Estimated Cost (3 bed semi house) £250-£450
    Estimated Annual Payback £150
    Estimated Payback Period 3 years


    Flat Roof Insulation:

    Flat roof insulation can be used when there is no loft and the insulation needs to be installed externally. It not only increases the thermal performance of the roof but can also help maintain the water tightness of the roof.

    The insulation comes in boards (typically measuring 1200mm x 2400mm) that can be cut to size which are laid on an air tightness barrier and sealed to create a water tight membrane over the roof.

    insulation-flat-roof insulation2


    Estimated Cost (20 square meters) £800-£1200
    Estimated Annual Payback £100
    Estimated Payback Period 8 years+


    Internal Wall Insulation (Solid Wall Insulation):

    Solid walls lose more heat than cavity walls – up to 45% of heat is lost. Internal Insulation can be fixed to properties that do not have cavity’s and do not suit external insulation. It is especially beneficial for period properties that may be listed and thus cannot have external wall insulation. The process involves fixing thermal backed plasterboard with taped joints to the internal walls. This will require skirting boards and plugs to be adjusted slightly and the internal space lost through extra insulation is between 50mm and 150mm. The boards can be fixed either using adhesive or plaster dabs.

    Because of the work involved and subsequent cost, internal wall insulation is best installed when a property is undertaking a major retro-fit or redecoration – this can significantly save on costs.

    Estimated Cost £6,000
    Estimated Annual Payback £450
    Estimated Payback Period 13 years


    External Wall Insulation (Solid Wall Insulation):

    Solid walls lose more heat than cavity walls – up to 45% of heat is lost. One of the easier ways to insulate a solid wall is to use external insulation. Whilst this may not be suitable for all houses, it is an effective way to insulate many solid wall properties.

    The insulation is added to the outside wall with several layers including: An Adhesive fix which joins the insulation material to the external wall. On top of the insulation is then added a reinforcing weatherproof coat and on top of this we add a reinforcing mesh. Finally the outer layer render finish is added:


    The outside render can be finished in many different ways to either suit your preference or to make the property look exactly as it was before. You can have a smooth finish in any colour you wish, or you could also have a synthetic brick finish where an imitation brick layer is fixed to make the house look as though it was completed in an external brick. Some examples are:

    Estimated Cost (3 bed semi house) £10,000
    Estimated Annual Payback £500
    Estimated Payback Period 20 years


    Floor Insulation:

    Floor insulation is very easy to install before you are laying new carpets/laminate flooring etc and should be considered at this stage. It merely involves laying an insulation board on top of either the concrete or suspended wooden floor and then laying the carpet/floor covering on top of this. The insulation boards measure approximately 50mm in depth. Special systems can be purchased to work with underfloor heating systems.

    Estimated Cost (3 bed semi house) £400
    Estimated Annual Payback £100
    Estimated Payback Period 4 years


    Installation cost assumes that the insulation is being conducted when new carpets are being fitted and the cost of clearing the room and removing old carpet is not included in the insulation cost.

    Draught Proofing:

    Draught proofing is a very simple and effective insulation measure that can save up to £50 per year. It is also a step that can easily be undertaken by yourself as a DIY project, although most installers / Green Deal installers will offer this service free of charge as part of a larger package.

    Types of draught proofing include:

    –          Windows: draught proofing strips for around the window frame

    –          Doors: the easiest method is to put up a curtain behind an external door

    –          Chimneys: fit a cap to unused chimneys

    Estimated Cost (3 bed semi house) £100
    Estimated Annual Payback £50
    Estimated Payback Period 2 years


    Heating System Insulation:

    Heating system insulation again is a very easy task to undertake and can be done by any keen DIY person. It involves lagging pipes (installing a thermal jacket around pipe wok) and installing a thermal jacket on your hot water tank. Again this is done by Green Deal installers for Free as part of a larger package of works undertaken.

    Estimated Cost (3 bed semi house) £50
    Estimated Annual Payback £10
    Estimated Payback Period 5 years


    Energy efficient glazing and external doors:

    Double Glazing / Triple Glazing / Energy efficient doors – all can be bought and installed as part of the Green Deal package. This will not only save you money on your heating bills and reduce your carbon emissions, but will also increase the value of your property.

    The cost for each house for supply and install will vary a great deal and below we have given an estimated cost for a typical 3 bed semi-detached property. Similarly the payback amounts will also vary depending on the cost and the windows that are being replaced.

    Estimated Cost (3 bed semi house) £4000
    Estimated Annual Payback £200
    Estimated Payback Period 20 years