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Spray Foam Insulation

SOLVED: How Much Insulation Do I Need In My Loft?


This is a bit of a piece of string question but, in reality, the answer to the question how much insulation do I need in my loft? has to be as much as you can afford!

The ‘why’ here is straightforward; energy companies love dipping their fingers into our pockets and the cost of domestic heating takes an ‘always up’ approach.

This leaves many of us considering a nearly ‘always off’ approach to the boiler. Well insulated homes are cheaper to run and allow you to turn down the thermostat whilst keeping the central heating on for longer. The result? Lower energy bills and a home that is heated more efficiently all year round.

How Much Is Enough?

Well, no insulation will leave your home feeling cold and unpleasant for large parts of the year, however hard you burn you cash. Today, the minimum recommended insulation is 270mm of traditional fibreglass insulation – the nasty, scratchy stuff that comes in rolls.

Your home will lose 25 per cent of its heat through the roof, so the benefit of installing insulation is a bit of a no-brainer.

Enough, however, may only be adequate in some homes and installing more than the basic recommended amount can be a worthwhile thing. Small homes in terraces benefit from insulation as much as more ample abodes, and in these homes, the 270mm level may be enough.

For larger, detached homes, the benefits of insulation will be much greater. These homes can make the most savings when it comes to energy costs, with the Energy Saving Trust estimating an average of £225 per year worth of cash savings on bills, with 0-270mm insulation installed.

Can You Have Too Much Of A Good Thing?

This is another good question; too much insulation is mainly a problem in terms of cost when it comes to the installation. Some methods of insulation can be DIY projects, albeit irritating and sometimes difficult ones.

Traditional fibre glass rolls of insulation are an ‘easy’ D.I.Y project , so this is the material to go for if you want to save on costs, and add more insulation than the basic 270mm.

However, the more insulation you install, the greater the upfront cost will be, and although you’ll benefit from lower bills, it will take longer to recoup those original costs.

Additionally, even the minimum insulation will normally be level with the roof joists, and extra will cover them.

This makes your attic more or less ‘dead’ space, as compressing insulation with boards and walkways reduces its effectiveness and rather defeats the point of installing more insulation!

Both spray foam and rigid insulation boards can also be applied to the roof itself, again, leaving the loft space as a useful area that can be boarded for storage, or converted into extra space!

Age-Related Insulation

How much insulation do I need in my loft is a question that can also depend on several personal factors. The most vulnerable people in cold weather are the very young, the extremely mature, or those in poor health.

For these groups staying warm in Winter can be literally a matter of life and death. For young, fit, healthy and active types, a poorly insulated home may be a nuisance but it’s probably something that an extra layer of clothing or a few extra hours down the gym can resolve.

For those in the more vulnerable categories, ensuring that the maximum amount of insulation you can afford is installed is no bad thing. Apart from the benefits of keeping warm in Winter – which include being more resistant to winter illnesses – there is also the cost saving issue to consider.

The more mature group may well be on a restricted income in retirement, whilst young families tend to have high outgoings and lower incomes than those in the middle of their careers. These groups can also benefit most from the bill reduction elements of fitting loft insulation.

So, How Much Insulation Do I Need In My Loft?

How much insulation do I need in my loft? It is an old question but, today, there are a few new solutions to consider. Spray foam insulation is a good option if you want to use you the loft/roof-space for anything other than keeping the weather out of your home.

In the case of spray foam the depth required compared to traditional insulation is considerably less.  This means that you get the same insulation benefits without the loss of a functional loft.

Both spray foam and rigid insulation boards can also be applied to the roof itself, again, leaving the loft space as a useful area that can be boarded for storage, or converted into extra space.

Ultimately, cost and personal circumstances will dictate the appropriate level and type of insulation you choose! For further advice, give our team of spray foam experts a call today on 0800 1700 636, or, alternatively, by simply clicking the button below!