Loft Insulation

For an effective way to reduce your heating bills, try insulating your loft.  It is a simple procedure that you can do yourself.  Without loft insulation as much as 15% of your heating costs could be lost through your roof, so it is a worthwhile exercise to save some money, as well as saving energy. 

How it worksBack to top

The insulation acts as a blanket which stops the rising heated air from the rooms below from escaping and traps it in.  It is also worth considering lagging your pipes and cold water tank too.

How much can you save? Back to top

If you do not currently have any loft insulation, you could save around £205 a year on your heating bills if you install the recommended 270mm depth of insulation.  Not only this, but this would also save around 1 tonne of carbon dioxide (CO2) per year.  In fact, about £710m could be saved per year if everyone in the UK topped up their loft insulation to 270mm, which would cover the annual fuel bills of around 740,000 households!  (source: The Energy Saving Trust).

The following table gives approximate costs, savings and paybacks for loft insulation:

	Loft insulation (0-270mm)	Loft insulation (50-270mm)
Annual saving per year (£)	Around £205	Around £60
DIY cost	From £300	Around £200
DIY payback	From 2 years	Around 4 years
CO2 saving per year	Around 1 tonne	Around 300kg

(source: The Energy Savings Trust)

Choosing your insulationBack to top

SPACE BLANKET
Space Blanket is a premium ‘encapsulated’ glass mineral wool product for use between 400mm ceiling joists or on top of existing insulation. It is used for the thermal insulation of pitched roofs at ceiling level and is usually laid in two layers, with the first layer between the joists and the second layer at right angles to and over the joists. It is also ‘compression packed’ for less handling - expanding when unrolled, lightweight and easily cut to size. The sleeved encapsulation is a part metallised polythene film that reflects heat and makes it extra easy and comfortable to install. Space Blanket should be laid silver side up for best performance.

SPACE COMBI-ROLL
Space Combi-Roll is a flexible glass mineral wool quilt which is lightweight, flexible, resilient and non-combustible.  The rolls are 1140mm wide and partially perforated to produce either 2 rolls 570mm wide or 3 rolls 380mm wide – making it easy for use between 400mm or 600mm ceiling joists.  Space Combi-Roll is primarily used for the thermal insulation of pitched roofs at ceiling level. However, it can also be used to thermally insulate floors and partitions, or wherever a lightweight mineral wool quilt is required. When used to insulate at ceiling level it is usually laid in two layers, with the first layer between the joists and the second layer at right angles to and over the joists.  Space Combi-Roll is easy to handle and install, being lightweight and easily cut to size.

Both of the Space products are virtually itch free and are made from a non-combustible inorganic glass wool, defined as mineral wool.  They are free from CFCs, HCFCs and any other material with ozone depletion potential in its manufacture and content and represents no known threat to the environment.  They are odourless, rot proof, non-hygroscopic, do not sustain vermin and will not encourage the growth of fungi, mould or bacteria and have a vapour resistivity of 7.00 MN.s.g.m.

THERMAWRAP
Thermawrap Easy Fit General Purpose Insulation is a CFC & HCFC free product that is both lightweight and flexible.  It is a durable material, 4mm thick, with high reflective foil facings to each side.  Fitting Thermawrap insulation will help to keep your house warmer in winter and cooler in summer and to exclude penetrating damp and reduce condensation.  Installation is quick and easy.

ECOHOME
Ecohome Non-Itch Recycled Fibre Insulation is made from user-friendly non-irritant, non-itch material that is free from floating fibres or dust and so avoids skin irritation and respiratory problems normally associated with other forms of insulation.  It will not deteriorate over time and will not be affected by water, mould, mildew or rot.  It is also resistant to vermin and insect attack.  Ecohome insulation is totally safe, clean and easy to install with no protective clothing required and it ensures a safe indoor air quality.  It is a direct equivalent to glass fibre, but is totally recyclable and uses recycled plastic bottles in its production.  It provides good acoustic properties to help keep your home or commercial environment quiet and free from noise pollution.  It has long term stability and is durable for 50 years plus!

How to fit your insulation Back to top

When fitting you insulation, we would recommend that you wear gloves, goggles and a dust mask, all of which can be picked up in store.  Once you have cleared the roof space of any clutter, lift all the insulation rolls into the loft and, starting at one end, unroll the first length so that it fits between the ceiling joists over the floor of the loft. Take care not to insulate below the cold water tank, if you have one.  Make sure not to block the eaves and to leave a gap of 25mm to allow ventilation to prevent condensation.  Do not squash the insulation down or compress it into tight corners or eaves as you will reduce the depth of insulation material and its effectiveness. Avoid contact between insulation and hot flues, chimneys and light fittings.  At the same time, you should also make sure to insulate your water tank and pipes, as an insulated roof space will be colder as it will receive less heat from below and will require frost protection.

View our how-to guide on insulating your home.

How much will loft insulation cost? Back to top

The amount you spend will depend on whether you have any existing insulation in your loft, as it may only need to be topped up.  However, insulation costs will be around £200 to £300 (for a three bed semi detached home), but this will vary depending on the size of your home.  It can usually pay for itself in under 2 years if no insulation was installed previously. This is based on a DIY insulation fitting – which is easy to do.  However, if you are planning to get your insulation professionally fitted, then costs may be higher.

How much loft insulation do I need?Back to top

Over the past 50 years the amount of insulation required in lofts has gradually increased as energy prices have risen.  Current building regulations recommend a minimum depth of 270mm.  It has been widely recognised that thicker insulation brings significant improvements to the energy efficiency of homes and the greater the thickness of insulation, the greater the energy and cost savings.  Make sure to measure the area of your loft and look for the packaging label for the area contained in a roll.

How do I find out how much loft insulation I have? Back to top

You can check if your home already has the recommended depth of insulation by simply sliding a tape measure or ruler down the side of a piece of loft insulation until it hits the plasterboard ceiling.  You can then check the depth and, if it is below 270mm, then you should top it up.

How long would it take me to insulate my loft? Back to top

After you have bought your insulation and cleared your loft of any contents, it can only take a couple of hours but it is probably best to allow about half a day. However, the length of time it takes will depend on the size of your house.

What sort of clothing should I wear when installing loft insulation? Back to top

We recommend wearing comfortable, loose fitting clothing and protective gloves. As lofts can be rather dusty places, we would also suggest that you wear a basic dust mask and plastic goggles which can be picked up cheaply in store.

What are the benefits of installing insulation? Back to top

There are many benefits including:

- Lower energy bills and great savings per year

- It could upgrade the Energy Performance Certificate of your home (Potential buyers will find a home that is more energy efficient a more appealing prospect.)

- Helps to combat global warming & climate change, as you heating system will emit less CO2

- Offers sound absorption.

- Your home will be warmer in cold weather

- Quick and easy installation

How can insulating my house help the environment? Back to top

A house that is well insulated needs to use less energy to keep it warm, which means that less CO2 is released.  This is because CO2 is produced when fossil fuels are burnt to create energy.  Due to large amounts of CO2 and other greenhouse gases accumulating in the atmosphere, Global Warming is occurring and this causes the earth’s temperatures (air and sea) to increase and sea levels to rise.  This in turn causes the planet's weather conditions to become increasingly severe. This effect is called Climate Change.  It is happening right now and you can play your part in trying to reduce these problems by effectively insulating your home and using less energy.

Useful accessories Back to top

Pipe insulation, fixing pipe tape, goggles, gloves, dust mask, ladders, measuring tape, a strong kneeling board.

Homebase buyer’s tips Back to top

'Don’t forget the loft hatch!  If you do not insulate your loft hatch, warm air can be drawn up through it.  You will need to cut a piece of insulation to size that fits properly to the size of the hatch and make sure that the edges are sufficiently draught proofed.' 

'Think of insulating your loft as an investment as it can save you a lot of money in the long run.  You can continue to enjoy its benefits all year and it could pay for itself in approximately 2 years.  And remember, once it is fitted, insulation is maintenance free!'

'Keep insulation away from ceiling lights (such as halogen down lighters) to prevent over heating.  Leave 150mm clearance around recessed ceiling lamps.'

'Whenever possible, lift electrical cables above the insulation to avoid overheating. Don’t cover high load cables such as those to cookers, electric showers and storage heaters.'

'Once your loft is better insulated, it’s important to insulate all water tanks and pipes to prevent bursts in freezing weather.'