8 Steps To Insulating Your Exterior Walls

Insulating your walls is a hefty task, and there are different ways to do it. The main objective of insulating the outer wall is to keep the rooms warm or at a stable temperature. This makes it easier to cool or heat the room based on personal preference.

Insulation is mostly done on inner walls. If your walls do not have cavities, then it is best to insulate them from the outside. Solid walls are perfect for exterior insulation. If you want your room to be climate efficient, then follow our step-by-step guide on how to insulate exterior walls.

But before we look at the process to insulate exterior walls, let us look at a few common materials used for this purpose.

Materials Used for Insulating Exterior Walls

The materials used to insulate walls keep the interior of the room warm and cozy. It has to be heat absorbent. But should not be too absorbing otherwise, it would cause the room to heat up excessively. With that being said, here are a few materials perfect for exterior wall insulation.

1. Fiberglass Batt Insulation

This insulation material is considered to be the best because of its comparatively low cost and effectiveness. Each batt is made from glass materials, which are mixed with other products. This gives the batt high moisture, and resistance, fire resistance, along with acoustic control.

2. Loose-fill Cellulose Insulation

They are also known as blown-in insulation. This insulation is made from recycled materials, so if you want an eco-friendly option, this should be your first choice. This is perfect for walls that have some cavities, and you want to insulate from the outside.

3. Spray Foam Insulation

This insulation material is made from polyurethane. This is applied in either open-cell or closed-cell formulations. The foam is applied on top of the wall, which gradually hardens. This acts like a barrier reflecting heat and moisture.

Apart from these, you will also need vinyl tape to wrap all the electric wires.

How to Insulate Exterior Walls?

Now that you know some common materials, let us look at how to insulate your exterior walls with them.

1. Create Joists on Walls

This will be the first step in creating insulation for your walls. You have to create joists on the outer parts of the walls. The common material for making joists is wood because of its heat-resistant nature.

The joists should expand throughout the walls, and you have to place the insulation batts in between them. So, make sure the joists are properly placed otherwise your whole insulation will fall apart if it comes loose.

2. Cut the Batts in Perfect Width

Your insulation batts do not come in perfect shape. You need to manually cut them according to the width of your joists.

Make sure it is the exact width and height of the gaps between the joists. If there is too much gap between the batt and the joist, heat will easily escape. Also, it will be a waste of material if the batts are too large. Use proper scaling and measurement to figure out the necessary batt size.

3. Wear Protective Equipment

When working with your insulation materials, wear protective gear at all times. This includes gloves, eyeglasses, a mask, and a long-sleeved dress.

The materials you are using can be toxic for humans. Some may even have allergic reactions to them. So, it is best to know what material you are working with and take protective measures accordingly.

4. Place the Batts

Once you cut the batts to the right size, you need to place them between the joists. Make sure these are tightly placed, so they do not come off.

If you cut them in the right size, they should stay in place without the use of any other sticky material. If there are large gaps either at the bottom or at the top, cut some extra batt and place them in such places.

5. Use Foams on Hard to Reach Areas

Your batts will not cover 100% of the wall and will be unable to reach certain areas due to their large size. There will be small unreachable gaps, especially near window panes, or door panels.

It is best to use spray foams to cover these areas, as they can easily enter these small corner gaps. Once the foam dries up, it will get hard as your insulation batts. If you find it hard to insulate your exterior walls alone, you can seek help from experts in spray foam insulation Houston to do the work for you. 

6. Split Batts around Walls with Electric Wires

If your exterior walls have electrical wires, do not place them directly under the insulation batt. This may cause the wire to heat up too much. So, the best solution for walls with electrical wires is to cut the insulation batt in half and pass the wire between them.

Placing the wire directly under the batt may create gaps from where heat or cold temperature can leak. Placing the wire in between the insulation batt will give you better results.

7. Do Not Stuff Batts Behind Pipes

Your exterior walls will have pipes and cables. When facing these pipes, do not place the insulation material directly under the pipe. This will compress the size of the batt. A compressed batt will not be able to function properly and might lose its insulating capability.

So, the best option would be to place them on top of the pipe or avoid using the pipe altogether. If the batt cannot maintain its full thickness, then it is best to avoid placing them in these areas.

8. Use Proper Sealants

Finally, once you are done with placing the batts, you need to ensure they are properly sealed. You can do this by getting acoustical sealants or caulk. Both of these materials are airtight and can trap heat. Before sealing, however, make sure that you place a 4-millimeter-thick poly on top of the batts.

This will prevent your batts from getting damaged from coarse materials. Then, seal the poly with the sealants and your insulation process will be complete leaving you with a more energy-efficient house.

Final Thoughts

Insulating exterior walls is one of the best ways to keep your room warm and cozy. It will save your electric bills, make your home look new from the outside, and will not reduce internal room space.