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SOLVED: Best Method To Insulate An Attic On A Budget

best method to insulate an attic

Your attic is probably like millions across the country – slightly smelly, very dark, stuffed full of boxes and due for a good clear out. This is all pretty normal. But is your attic insulated?

If not, you may be paying far more for your energy bills than you need to be and furthermore, you could be missing out on turning your attic into a usable space that is truly practical (and not at all scary!).

It is estimated that around 25% of the heat that is lost from our homes heads out through the roof. This is hugely significant as our homes are made up of doors, windows and walls that seem to do a better job at keeping heat in than the largest structure – the roof.

Obviously heat rises, stealthily making its way out of the roof – which is usually poorly insulated.

The best way to prevent this is to place a barrier of insulation between the main part of the house, and the roof itself. Not only will this prevent heat from being lost from your home, but it will prevent cold air from entering.

But what type of insulation should you choose, and where should it be placed: against the roof itself or on the floor of your loft? It’s time to find out…

best method to insulate an attic

If water makes its way in through the roof, it can be difficult to get dry. Your belongings can also become damaged from the cold and the damp. However, you are not having to heat the loft space as well as your home which can add a substantial amount to your heating bills

A Warm Loft: The Definitive Answer

If you insulate the underside of your roof directly, you will have what is known as a warm loft. It means that the barrier to warm air leaving the house is at roof level, rather than at loft level.

Your loft space will be warmed by the rest of the house and will therefore be more habitable. This has one main advantage. There is less difference between the temperature of the air in your loft compared to the rest of the house, and therefore less chance of condensation forming where the cool air meets the warm air.

A Cold Loft: The Definitive Answer

This is when the insulation is placed on the floor of the loft, and forms a barrier for warm air leaving the house and entering the loft at all. The loft then becomes a very cold spot, where condensation can become an issue.

If water makes its way in through the roof, it can be difficult to get dry. Your belongings can also become damaged from the cold and the damp. However, you are not having to heat the loft space as well as your home which can add a substantial amount to your heating bills.

The cold loft can, ironically, become very warm in the Summer months, as warm air enters through the roof and becomes trapped.

best method to insulate an attic

Once again, it is worth pointing out that when you add insulation to the floor of your loft you are creating a barrier between the warm air of your home, and the cold air of the loft. This may seem like the point, but any time those two environments meet (such as when you open the loft hatch), you will cause condensation

Wool Insulation: The Cold Loft Insulation

The above types of insulation are generally used in the cold loft scenario. They are by far the cheapest options, and are a great solution if you are on a budget, and want to achieve the best all round insulation for your money.

The government has recognised the importance of insulation and have worked together with energy companies under the Energy Company Obligation (ECO) scheme to allow cheap (and often free) distribution and installation of this type of insulation. These can also include wall cavity insulation where appropriate.

It is recommended that around 270mm of wool insulation is added to the floor of your loft to achieve the best possible insulation for your home. This will prevent the loss of heat from your home into the loft, and will help you to save around £140 per year in your energy bills.

Installing this type of soft insulation can have its good points and its bad points. It is easy to lay, and can be done as a DIY job. It also requires only minimal outlay, and offers a reasonable thermal return.

However, it does take up a lot of space, and on the whole, the depth required exceeds the depth of the floor joists, meaning it is hard to board out your loft without building up the floor, and reducing overall head height.

Wool insulation is also a haven for small animals, such as mice and squirrels, and can be easily moved around, causing cold spots to develop. Also, if this type of insulation becomes wet, you will find it very difficult to get dry, and you may have to replace any wet sections.

Once again, it is worth pointing out that when you add insulation to the floor of your loft you are creating a barrier between the warm air of your home, and the cold air of the loft. This may seem like the point, but any time those two environments meet (such as when you open the loft hatch), you will cause condensation.

This can lead to problems with mould, mildew and general damp issues. Plus the cold environment can have a negative effect on anything you choose to store in your loft.

best method to insulate an attic

Open cell spray foam is a less dense mixture with air pockets. It allows air to pass through, but still has an excellent thermal value compared to other insulation options on offer!

Spray Foam Insulation: The Warm Loft Solution

Spray foam is the perfect way to achieve a warm loft solution. A warm loft will maintain a more even temperature year round, reducing the issue of condensation and reducing the amount of warm air that is lost through your roof.

Spray foam is a mixture of isocyanate and polyol resin that is mixed together to form a liquid that when sprayed, will expand to up to 60 times it original volume. This makes it a perfect way to fill holes, nooks and crannies of the the exact type you will find your loft.

The mixture is usually sprayed between the rafters of your roof to a depth of around 100mm. This offers the same thermal value as 270mm of wool insulation, and therefore takes up much less space overall. You can then either leave the insulation as it is, or cover it with plasterboard to make the loft look more attractive.

There are two main types of spray foam insulation. Closed cell is more dense and is often used to offer additional structural elements to your roof or walls. It offers good insulation, but does not allow for adequate ventilation.

This means it can cause condensation issues as heat builds up in the loft space. You will need to use additional ventilation if you choose to use this type of insulation.

Open cell spray foam is a less dense mixture with air pockets. It allows air to pass through, but still has an excellent thermal value compared to other insulation options on offer.

You will find that this is often cheaper than the closed cell insulation formulations, and it can be used in more applications, including commercial projects, such as warehouses.

If you are planning on using the loft as a play room or study (you will need to go through Building Regulations if you want to turn it into a bedroom) this is a great way to maintain head height and get a usable warm space.

So, the choice is yours. You can choose the cold attic method to insulate your home, or the warm attic method. Each have their own benefits and disadvantages, but the warm loft method gives you more flexibility over how you use your loft space and it has fewer drawbacks when it comes to the insulation material itself.

Love up your loft the easy way, with the help of spray foam insulation. Take the first step to transforming your loft into a habitable hideaway today, by simply calling 0800 1700 636, or by simply clicking the button below!