How to Insulate My Roof

If you haven’t insulated your roof and rafters, they’re costing you a lot of money in the form of energy bills for every minute that you are using the heating system. This is not an ideal situation to prevent heat loss and save money, as heat will rise and escape through the roof and rafters.

Luckily, insulating your roof and rafters is not an expensive procedure. If your loft is easy to access, doesn’t have damp problems and is not a flat roof, you can most likely insulate it yourself. In cases where there are damp problems or a more complex insulation system is needed, a professional installer should be used. The insulation of a flat roof and roof spaces afflicted with damp always requires the advice and work of a professional.

Here, we have put together a guide on different types of roof insulation available to you and how you can install it yourself. 

Estimated Time: 10 hours 

Level of Expertise: Intermediate 

Tools and materials needed to insulate your roof:

• Goggles
• Tape measure 
• Insulation boards 
• Ladders
• Hard hat 
• Safety knife 
• Mask

Why is it Important to Insulate the Roof and Rafters?

It is really important to add insulation to improve the energy efficiency of a property and ensure heat does not escape through the top of the building. Beyond this, it also helps with soundproofing, too, giving it multiple purposes and uses. With proper insulation, you can also turn the roof area into a comfortable living space that can be enjoyed by the whole family. 

Different Types of Roof Insulation 

There are several insulation options available to choose from when insulating your roof. Here, we have some of the insulation options we sell for roof insulation. These include:

1. Rockwool Flexi-slab

The Rockwool Flexi-slab is a multi and dual-purpose thermal as well as acoustic insulation material.The flexible edge offered by the Rockwool Flexi-slab allows for a perfect fit that is reliably retained between the product and its supporting framework for convenient installation and optimal effectiveness. Along with having excellent thermal, acoustic, and fire properties, it is a noncombustible material.

1. Knauf Flex-slab 

Use the Knauf flex-slab as the fast and convenient way to handle and install roof insulation for any kind of roof. It has flexible edges on all four of the slab’s sides, making it much easier for installation. The Knauf flex-slab is made using ECOSE Technology and recycled material. It has also been awarded the A+ generic BRE Green Guide rating.

1. Ecotherm 

Ecotherm may also be used for roof and rafter insulation. Ecotherm is rigid insulation boards that will quickly and easily achieve the needed thermal standards in pitched as well as flat roofs. The use of Ecotherm Eco-Versal allows you to insulate the roof space without the need to alter the thickness of the construction or your method; this is because it needs about half the thickness of the conventional insulation materials to give the same level of thermal performance and thus space is considerably maximized.

1. Kingspan TP10

Kingspan TP10 is a high performing, rigid thermostat and fiber-free insulation option which is faced on both of its surfaces with low emissivity composite foil facing. It is also aimed at the insulation of warm roof spaces in the face of unventilated or ventilated pitched roofs. It is commonly used as rafter level insulation for tiled or slated roof spaces which are also pitched. It It is readily available in different size options and also manufactured according to the size required. Kingspan TP10 boards may be used for insulation between, over and under rafters, and as pitched roof sarking.

Insulating your roof

Depending on the size of your property and roof, and the insulation material you’ve chosen, you’ll find that this takes a bit of time to do right. Don’t cut corners or you may have to invest more time and money later.

That said, follow these steps to insulate your roof.

Step 1: Clearing your loft 

Tools you’ll need:

• Goggles
• Ladders
• Hard hat 
• Mask

Making sure you’re properly prepared for the insulation process is important. Before you make a start, ensure the space is ready for you to work in.

Clear anything in the loft to another room in the house, or a shed or garage if you have one. Lofts are often used for storage, so finding space can be challenging but it’s better than having to work around your belongings.

If you’re planning to get this all done in a day, it won’t be too much of a disruption but if it will take longer, make sure you’ve thought about where to store everything.

Step 2: Measuring the roof

Tools you’ll need:

• Goggles
• Tape measure 
• Ladders
• Hard hat 

For the insulation of the roof and rafters it is beneficial to use rigid boards as opposed to wool or rolls. The choice is yours, but you’ll find them easier to use even with the extra preparation.

To use rigid boards, you’ll need precise measurements. Measure the roof, measure the rafters and the joints. This will tell you how many boards you need and what sizes.

Wool and other materials can go between these beams, but will need adhesives and can take longer as you’ll need to pack the insulation in and account for it to compress a bit. Even insulation is important for a good R-value.

Step 3: Cut the Rigid Boards 

Tools you’ll need:

• Goggles
• Cutting tools
• Insulation boards 
• Ladders
• Hard hat 
• Safety knife 

The rigid boards need to be cut to size to fit the gaps between the rafters. Once measured, cut the boards to size so they are ready to be placed between the beams.

With even gaps, you can test this and mark on the boards where exactly you’ll attach them, which will save you time as you’ll know exactly what you’re doing.

The cutting is best done on a stable surface. If you don’t have this in the loft, use a workbench while on stable ground. It can serve as a template for other boards.

Step 4: Adding The Insulation to Your Roof and Rafters

Tools you’ll need:

• Goggles
• Tape measure 
• Insulation boards 
• Ladders
• Hard hat 
• Safety knife 

Once they are cut, ensure there is a relatively tight fit between the edges so that the board can be stapled to the rafters and then simply fit them into place.

Start at the top and work your way down to the floor of the loft. This will make it easier to handle the boards and work with any odd gaps once most of the insulation has been installed.

You must also ensure there is a 50mm gap between the roof and the insulation board, which is something other insulation materials don’t require.

You may need the help of someone else for this step in order to secure the boards in place while you staple them.

Step 5: Check for gaps

Once all the boards are in place, check the roof for any gaps.

If all went well, your measurements will have prevented this but over time, wood can bend and warp, leaving some gaps. If this occurs, you need to plug that gap to ensure heat is kept in.

This might mean a new board cut in a new way or a filler material that can fill the gap. Depending on th hole, you’ll have to decide which is the best option.

Step 6: Refill the loft

Once you’re happy with the insulation, you can return everything you removed from the loft back to the room.

Being used for storage by a large number of homeowners, you’ll not only notice bett energy usage but better conditions for storing your belongings.

Ready to Save Money on Bills and Enjoy a Warmer House? 

Now that you have insulated your roof and rafters, you will notice a massive difference in the warmth of your house. Your property will retain the heat much better as heat will not have as much chance to escape from the roof area. There will be no more paying excessive prices for heating and your home will be more comfortable, which is a big win all round!

We hope you have found this guide useful. If you have any questions about our products or the best boards for insulating your roof and rafters, please do not hesitate to contact us. Our team will be happy to help!