If you find your house is particularly cold or chilly, or even find that pleasant evenings are marred by annoying breezes, it may be time to consider some loft insulation. Your first task will be to go over the entire building as best you can – perhaps combine the job with a thorough spring clean, which will enable you to take advantage of moving large heavy furniture items that might be blocking evidence of structural damage or small cracks and gaps. If you find no evidence of damage or serious issues that need repair then the chills are most likely caused by a lack of shielding from the elements.
How to improve your loft insulation
Your next task will be to decide what level of protection you will need. Lagging is measured in R-value, which is essentially the resistance of a substance to heat flow. The higher the R-value, the greater the 'sealing' effect. This means that if you are in an area that is subject to great extremes of temperature you will need insulating material with a much higher R-value than someone living in a fairly temperate zone.
There are several ways of applying the material to the desired area. The first is the loose-fill method of insulating a room or area. Specialists use high-tech equipment to spray on a layer of the material into crevices and corners and in an even layer on the floor of the loft. This material is made up of recycled bits and pieces and can include fibre-glass, cellulose or mineral wool. This is an easy-to-apply method of lagging, but the materials can settle, thereby losing much of the protective effect.
Another form is 'batt and roll' shielding, also known as blanket insulation. Great rolls of soft fluffy material is unrolled extensively over the floor of the loft or even stapled to the underside of the roof in order to create a layer between the occupants of the house and the elements outside. An added advantage of this type of layering is that it works effectively as soundproofing too.
Spray foam is available too, but many experts warn that applying a rigid layer to the inside of the roof can affect the roofs natural flexibility which can lead to cracks forming. This type of foam can also impact on the roofs 'breathability' which can encourage the growth of mould and the start of rot in wooden joists. Experts have strongly discouraged the use of foam lagging, claiming that it tends to cause greater, more expensive problems for the home-owners at a later stage in life.
Loft fans are a method of circulating air, especially the hot air that builds up in the loft, throughout the whole home by expelling the hot air and drawing in cooler air. In principle the idea sounds fine, but practical calculations have proven that a more traditional form of lagging is infinitely more cost effective – even in hot areas, like Florida, an loft fan can take up to twenty years to pay for itself!
- Lagging can be applied in many areas: in the wall cavities, the lofts and even in a crawl space under the home
- There are some DIY options for applying lagging to your home, but do be careful and make sure the method you are using is not going to do any harm over time
- Wear a face mask and gloves when using fibreglass as the tiny fibres can penetrate into your skin and itch and burn.