{"id":238,"date":"2011-04-11T15:05:06","date_gmt":"2011-04-11T15:05:06","guid":{"rendered":"https:\/\/www.anytrades.co.uk\/?p=238"},"modified":"2011-04-11T15:05:06","modified_gmt":"2011-04-11T15:05:06","slug":"cavity-wall-insulation","status":"publish","type":"post","link":"https:\/\/www.local-quotes.co.uk\/guides\/energy-saving\/cavity-wall-insulation\/","title":{"rendered":"Cavity wall insulation"},"content":{"rendered":"

Homes built since the mid 1930s have probably been built with a cavity wall. This provides a small space between two layers of bricks. It provides some thermal protection but that can be improved on. Homes without wall insulation can lose up to 35% of their heat.<\/p>\n

To check if you have a cavity wall the best way is to look at the pattern of the bricks on the external wall. If the bricks are laid length-ways with one brick laid to cover the join of the bricks below – that\u2019s a cavity wall. If the wall is laid one brick length-way and the next end-ways that\u2019s a solid wall.\"Cavity<\/p>\n

Cavity wall insulation needs to be undertaken by an expert. They have the equipment, and the expertise to judge exactly how much material is required to give your home good insulation.<\/p>\n

The method is to inject the insulant into the gap between the two skins of the wall.<\/p>\n

The material most normally used is foam, alternatives include mineral or glass fibre mixed with a binder or beads or granules.<\/p>\n

All the materials are treated to be water resistant to prevent damp entering the building, and are also fire retardant.<\/p>\n

These forms of insulation should come with a 25-year guarantee issued by CIGA<\/a> (Cavity Insulation Guarantee Agency) so shop around.<\/p>\n

A question to ask would-be installers is does the material and work comply to British Standards or the British Board of Agrement (BBS). If they don\u2019t – go elsewhere.
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Cavity wall tips<\/h2>\n

Any problems with condensation need to be tackled before insulation is installed.<\/p>\n

Walls must be dry before the work can be carried out, sealing in damp won\u2019t solve anything.<\/p>\n

You need a professional to check out what is causing the damp and how it can be eradicated – that includes inspecting damp courses to see if they are sound and fit for purpose.<\/p>\n

It is vital not to cover any ventilation already provided in the building and to check if additional sources are recommended by the installer.<\/p>\n

How long will it take to install cavity wall insulation?<\/h2>\n

The whole process shouldn\u2019t take more than two or three hours, depending on the size of the property and access to the exterior walls.<\/p>\n

The installer drills holes at regular intervals and injects the insulant through them. Once in place the holes are plugged – leaving little evidence that anything has been done.<\/p>\n

How you can help the installer<\/h3>\n

A sensible move is you tell your neighbours what is going on and, if applicable, advise them to move any cars so that they don\u2019t get covered with dust.<\/p>\n

Neighbours would probably also appreciate being warned that there will be some drilling going of for a little while.<\/p>\n

Removing pictures or other valuables that might be dislodged through the vibration is recommended.
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But what kind of materials do i use?<\/h3>\n

There are a range of materials available for lofts, solid and cavity walls – lets take a look at some of them.<\/p>\n

Insulating your loft<\/strong>
\nYou may already have some insulation in your loft – but modern recommendations say that at least 270mm (8 inches) is needed, rather that the much thinner layers used in the past.<\/p>\n

The first two types we look at are often classed as quilt insulation, as that is quite literally what they do – form a quilt over the floor of the loft.<\/p>\n

Mineral wool<\/strong>
\nThis is the type of product most people think of when talking about insulating a loft.<\/p>\n

Modern versions of this material have good environmental credentials as they are made from recycled glass. The product is spun into fine strands of wool treated with a binding agent. It is fire resistant, will not rot and discourages vermin.<\/p>\n

Easy to install a competent DIYer will be able to lay the material. The recommended way is to roll the mineral wool between the joists and then cover with a second layer the other way to cover the joists themselves – as this is an area where most heat is lost.<\/p>\n

Anyone using this material should wear masks and gloves to protect themselves.<\/p>\n

See the general rules at the end of this section for safety tips.<\/p>\n

Sheep\u2019s wool<\/strong>
\nA product that is gaining in popularity as people look for environmentally-friendly solutions to insulating their homes.<\/p>\n

Sheep\u2019s wool has declined in popularity in the fashion market, so its alternative role as an insulation material is making use of a natural product that was being thrown away and wasted.<\/p>\n

Laid in the same way as mineral wool, it doesn\u2019t have the skin irritation problems that some materials can give – and its treatment to make it fireproof and insect repellent make it a safe option.<\/p>\n

Blown insulation<\/strong>
\nThis needs an expert installer as it requires specialist equipment to blow loose granules onto the floor.<\/p>\n

Its advantages are that it can be used in areas that are hard to access by other methods.<\/p>\n

Its down-side is that if the loft is to be used for storage it does need to be covered by boards to stop it being trampled on – or even blow about if the loft has draughts.<\/p>\n

The materials used are either granules of mineral fibres or paper.<\/p>\n

Granular insulation<\/strong>
\nLike blown insulation this needs to be covered by boards if the loft is to be used for storage.<\/p>\n

Using this method, granules of recycled paper, vermiculite, mineral wool or cork are quite literally tipped onto the floor and then spread around.<\/p>\n

Multifoil<\/strong>
\nThis material is different from the others we have looked at, as it isn\u2019t laid on the floor. It is inserted between the roof rafters – a good idea if the loft is to be converted to a room, as it lets heat rise from the rooms below to help warm the space.<\/p>\n

Multifoil lives up to its name – it is layers of foil sandwiched together with foam or soft dry fibres and then bound together. This method creates air pockets to trap heat while the foil reflects warmth back into the room.<\/p>\n

Boards<\/strong>
\nIf you are thinking floorboards – forget it! Like multifoil these boards are inserted between the rafters.<\/p>\n

They are constructed of polystyrene extruded to become a rigid board. Boards are fitted with screws or nails, but there must be a gap between the roof tiles and the insulation to prevent problems with condensation.<\/p>\n

They are a solution if the loft is to become a room, so are a good option while undertaking renovation work or even on a new build property.
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Important tips to remember when insulating a loft<\/h3>\n

The idea of insulating a loft is to keep your home warmer, not to create problems so just read the following tips and avoid the pitfalls, while also gaining more benefits:<\/p>\n