A well-insulated loft can save you up to 40 per cent on your energy bill. Loft insulation cost isn’t as high as you might expect. Kitchen remodels, for example, often cost between 5 to 10 per cent of the price of your home but saves you much less money over time.
How do you know what kind of insulation you need, what kind of job needs to be done, and how much it will cost on average?
We’re about to pack in as much information as we can in this introductory article. Time to grab a cuppa and get cosy.
Insulation Types and R-Value
Determining the material you want to use for insulation and how much of it is a tough decision at times. For that, there’s a type of rating called an R-value, which is a rating of heat conduction.
This doesn’t measure convection, radiation, and air infiltration. The basic gist of that means that insulation is rated as a barrier to heat, but heat can still eventually flow through insulation.
Insulation can be gradually heated, and the many thousands of holes and cracks in bare construction will create airflow. Below is an unordered list of common insulation materials and their the corresponding R-value:
- Fibreglass: 2.2 – 2.7
- Mineral wool: 3.0 – 3.3
- Cotton: 3.7 – 3.8
- Sheep’s wool: 3.5 – 3.8
- Cellulose: 3.2 – 3.8
- Spray Foam: 5 – 6
These different materials come in different shapes and forms, for the most part. Even spray foam insulation material can even come as sheet insulation with reflective backing. Each insulation and type has its drawbacks and benefits.
Some different speciality insulator manufacturers have calculators you can even use, but generally a professional can give you the best idea of what will work in your loft space.
Batt or “Rolled” Insulation
Batt or “rolled” insulation comes in bundled rolls. These go between the studs in your loft and cut them when they would go over a joist. Material that comes this way would be mineral wool, fibreglass, cotton, and even treated sheep’s wool.
Rolled insulation often, but not always, comes with paper or foil backing to help keep it together and to reflect heat more efficiently. This is perhaps the most common form of insulation.
Loose Fill or “Blown-In” Insulation
Common loose fill, or blown-in, insulation is mineral wool, fibreglass, cotton, and sheep’s wool. Sheep’s wool has been mentioned a couple of times. We should mention that while it is on the rise for popularity as a natural and green insulation product while retaining sustainability and high quality as an insulator, it is still an expensive choice.
As a loose fill, it might be the best choice. Consider that loose fill means that the material is free to blow around or float in the air. Sheep wool tends to stay together better, and it isn’t an eye and skin irritant. Lanolin, naturally found in sheep’s wool, soothes skin and is highly sought after!
A bonus of sheep’s wool and lanolin is that while it is a natural product it is naturally flame retardant. For these reasons, sheep’s wool as a loose fill option might be your best choice.
Again, always talk with a professional first.
Spray Foam Insulation
Spraying foam sounds just as caustic as it is, while it is being spread and sets. The bonus is that it is extremely insular, and has excellent sound buffering qualities. The downside is that it’s quite expensive to install as a material.
However, the best way to use it is in the case you want to have a so-called “warm” loft. It keeps heat out of the loft altogether, as well as a sound buffer to make it a comfortable extra space in your home.
However, if you are not wanting to make it another livable space, you can still insulate the same as you would for loose fill insulation.
Choosing a Warm or Cold Loft
This brings us to the subject of having a “warm” loft or a “cold” loft. This is somewhat confusing, but a cold loft is one that is cold in winter and hot in the summer. Essentially, it is uninsulated, and “exposed” to the heat or cold outside.
This is an important consideration since pipes will need to be insulated so as not to freeze during low temperatures. The other thing to think of is as a storage space, items might not deal with constantly fluctuating temperatures.
A warm loft is one which is insulated to provide a barrier from the outside elements, including noise. This creates a temperature-controlled storage space or living space.
The Factors Affecting Loft Insulation Cost
So, let’s get to the nitty-gritty. How much is loft insulation? It depends on what kind of insulation you’re using, and how you’re using it—in a cold or warm loft.
The price fluctuates a bit for installations, but batt insulation typically comes in at £2.50 per m2. Foam insulation takes about 4 hours in most cases, is best for a warm loft, and costs the most, unfortunately. Depending on the thickness of the spray foam you need, between £40 and £70 per m2.
Finally, we’re answering “how much does it cost to insulate a loft?”
£55 per hour for typical installation. £65 for skilled installation around junction boxes and if you are installing downlights as well. Since most jobs come between 2 to 4 hours of labour, that means £210 to £260 on average.
Why would you need that skilled labour for installation? Plumbing and electrical in the loft, whether cold or warm, require special handling. Plumbing requires insulation, while electrical like downlights requires that insulation stay away.
A professional can give you a quote for your square meters, thickness and possible time required for a more accurate estimate.
Warm and Cozy
Now you know that loft insulation cost doesn’t have to be mysterious and scary. Especially when you can sit inside your warm loft, having a cuppa while you’re looking out your window on a cold day.
Even better if you can enjoy your cuppa with great articles on home, tech, and lifestyle tips. We are here to help you save money and give you great life hacks along the way.
Keep reading to see what you can find out!