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Spray Foam Insulation

Attic Insulation Guide: All You Need to Know

Attic Insulation guide

Attic insulation is one of the most effective steps you can make to improve the energy efficiency of your home. Without proper insulation, your home loses 50% of the heat inside.

The heat is lost primarily through the roof and walls, although heat can also escape through the floor, especially if the rooms aren’t carpeted.

If you live in an older home, chances are, the walls have cavities, cracks, and holes, that allow for ample air leakage.

Installing insulation in your loft is quick and easy, and if all households in the UK installed it, the country would save an enormous amount of energy.

With this in mind, we’ve compiled the following attic insulation guide, exploring the options on offer, their plus points and pit falls, and which is the most cost-effective choice overall. Let’s get started…

How Much Insulation Do You Need In A Attic?

One of the first questions people ask is how much insulation is necessary to achieve results. You need to know that British building regulations require a minimum of 270mm of insulation between the joists for a loft. And while that is the minimum, some older houses have as little as 25mm.

Bear in mind, existing insulation is often compressed by storage boards laid over the top. This makes the insulation much less effective overall.

You can always install “blanket insulation”, which is loft roll. However, if you want to use your attic, you need solid insulation on top of the joists.

Depending on the material you use, the thickness of your insulation will vary. However, what you need to strive for is a high R-value. In a loft, the minimum is a R-value of 6.1, but you should strive for 7.

Attic Insulation guide

If you have an inaccessible loft space, the best option is to call a professional insulator. Professionals use specialist equipment to blow insulation material, into the appropriate cavities and areas

What Will You Use Your Loft For?

Another important factor in deciding attic insulation is the purpose of your attic. What will you use it for? Depending on what you use it for, you need to install appropriate insulation.

For example, an attic with easy access, and no damp/condensation problems, can be insulated with minimum hassle and upheaval. For easy access and regular loft joists, you can use rolls of mineral wool insulation.

If you plan to use the loft as a storage space, you do need to lay boards over the joists. Be careful not to insulate only between the joists before laying boards over. The insulation won’t be thick in that case. You can always raise the level of the floor to fit enough material beneath.

If you want to use your loft as a living space, you need to insulate the roof itself, not the loft floor. For this purpose, you need to install insulation between the roof rafters.

Why Install Attic Insulation?

The biggest reason homeowners install loft insulation is to improve the EPC rating of their home. Insulation saves money by preventing heat loss.

When you do not have proper insulation in your loft, heat escapes through the roof. Approximately 25% of heat is lost through the roof, and 35% of heat is lost through the walls. Insulating your loft will produce a barrier that will slow down the transfer of heat.

You need to insulate at the joists, and at the rafters. According to building regulations, the goal is to reach a U-value of 0.16. In other words, you need around 300mm of blanket wool insulation. Other types of insulation can produce the same U-value with less material.

Insulating the rafters can be done in four different ways. One is with netting and wool insulation, the second is with solid insulation board, then you have reflective foil, and the fourth is spray foam insulation.

The benefits of insulating the loft are lower heating bills, improving your energy efficiency rating, increasing the value of your hose, and reducing the carbon footprint of your home.

Attic Insulation guide

This is the most common type of insulation. You can install it yourself, but there are many more energy-efficient better options available

Types of Attic Insulation

There are many different types of loft insulation on the market today. You can choose any of them, but it is always recommended that you look at the advantages and disadvantages of each insulation product before you purchase. Here’s a list of the key contenders:

Fibreglass Batts

This is the most common type of insulation. You can install it yourself, but there are many more energy-efficient better options available.

Pros:

– Easy for a D.I.Y project

– Easy to install in accessible spaces, such as exposed wall cavities

Cons:

– Fibreglass is not as good as filling cavities and cracks

– Rolls of blanket insulation can be too bulky to fit into small spaces

Attic Insulation guide

According to building regulations, the goal is to reach a U-value of 0.16. In other words, you need around 300mm of blanket wool insulation. Other types of insulation can produce the same U-value with less material

Loose-Fill Insulation

Made from several lightweight materials, loose-fill insulation can contain cork granules, mineral wool, and cellulose fibre. Some types feature recycled newspaper as well.

Pros:

– You can easily fit it between irregularly spaced joists

– You can easily place around obstructions

– Great for improving existing insulation in attics

Cons:

– You need safety equipment for installing it

– Can come loose in draughty lofts

Attic Insulation guide

Bear in mind, rafters are not usually very deep, so you might have to insulate over them. When you want to use the loft as a living space, you need to insulate walls and around dormer windows as well

Blown Fibre Insulation

To install blown fibre insulation in your home, you need to hire a professional contractor. He will blow the insulation into the gaps between the joists.

Pros:

– Quick and easy when you hire a professional

– Ideal for areas that are not easily accessible

– Light and convenient to handle

Cons:

– Usually more expensive than traditional loft insulation

– Not recommended for draughty lofts

Attic Insulation guide

Only a professional can achieve the desired thermal efficiency, with very little depth of spray foam. Yes, hiring a professional can be more expensive, but spray foam is proven to be the most cost-effective material in the long run

And Even Sheep’s Wool!

Just when you thought you’d heard it all! Sheep wool is not an irritant, unlike mineral wool, for example. So how does it far against the more familiar insulation materials on offer? 

Pros:

– Material absorbs moisture

– You can install without wearing protective equipment

Cons:

– For rafters, you need a more rigid form of sheep wool

– Sheep wool loses its thermal insulating qualities when squashed

– Sheep wool is much more expensive, due to availability and logistics

Attic Insulation guide

Thanks to its expansive nature, air leakage is prevented, ensuring that heat in the home’s retained. Suitable for both old and new buildings, spray foam can be used for insulating difficult areas, such as the rafters in dormer style homes.

Why Spray Foam Does It Better

Spray foam has become one of the most popular insulation materials in recent years. The advantages of spray foam are many, but one of the biggest advantages is that spray foam provides a superior, air-tight seal. The product also possess soundproofing properties as well.

For your loft, a layer of foam is sprayed into the rafters. It is recommended that you hire a professional for this task.

Some estimates show that you will get back your investment in three years, thanks to lower energy bills overall.

In fact, spray foam insulation delivers 50% more energy savings than any other roof insulation material on the market. The foam expands, and completely fills all cavities and voids.

Attic Insulation guide

If you hire a professional contractor, he will make sure that the insulation is installed properly, and eliminate the problems that inevitably occur in D.I.Y insulation attempts.

Spray Foam for Attic Insulation: The Summary

Cons of Spray Foam

Everything has its downside, and so does the best attic insulation material. Spray foam can be more expensive than the other insulation options on the market, but it is also guaranteed to last for many more years as well.

Furthermore, it’s not the ideal option as a D.I.Y project, and it is advised that a professional installer insulates your property when using Home Logic Spray Foam.

One of the downsides and problems of spray foam loft insulation is that usually there is no room for the roof to breathe. This happens when the spray foam is applied to the undersides of the roof slates or tiles, without adequate training to inform installation.

Because of that, there is no way to keep the ventilation gap, which eventually traps moisture. It is important that you leave ventilated gap between the insulation and the tiles.

Attic Insulation guide

Spray foam creates a barrier which protects your home, and insulates the area effectively. Home Logic Spray Foam expands to one hundred times its size when in place, which ensures it gets into all the hard to reach places with ease!

Benefits of Spray Foam

When looking for the best attic insulation material, spray foam could be just what you are looking for. It’s environmentally safe, fire rated, and it doesn’t hold or absorb water, thereby eliminating damp from the outset.

Spray foam creates a barrier which protects your home, and insulates the area effectively. Home Logic Spray Foam expands to one hundred times its size when in place, which ensures it gets into all the hard to reach places with ease.

It comprises of organic chemical compounds, making it safe for everyone in the home.

In addition to this, you will find that you can save money on your energy consumption, as Home Logic Spray Foam creates an air tight seal, which provides a host of health benefits in the long run.

Furthermore, you will find that it provides you with a comfortable temperature in the home to your requirements, and comes with the added benefit of a twenty-five-year manufacturer warranty.

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