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How to Build Dormers in a Roof | Comprehensive Guide

how to build dormers in a roof

When looking at a roof, sometimes you will see dormers built into it.

Dormers are essentially windows on an angle that jut out from the top of your home so they may add some architectural interest to your structure and give yourself more space in which to live or work.

There is no set way on how to construct these so you may need to use a bit of creativity when learning how to build dormers in your roof.

Building dormers in a roof is not as complicated as it may seem. With the right tools and knowledge, you can build your own dormer and enjoy all of the benefits that come with it.

We will discuss what to do before building a dormer on your roof, how to build one safely and efficiently, and what type of materials you’ll need for this project.

Dormers are small, secondary structures that project from the sloping surface of a roof.

They allow for more headroom and daylight in an attic space by adding windows to what would otherwise be a low-ceilinged area.

Dormers also provide architectural interest to your home’s exterior, which will increase its value as well as your enjoyment of the space.

What Is A Dormer?

A dormer is a window that juts out of the roof of your home.

They are primarily used to provide extra living space for attic rooms, but they can also be designed as architectural features on roofs with more than one floor.

Dormers may seem complicated, but learning how to build them is not too difficult once you know what materials to use and how to build them safely.

Guide to Building a Dormer on your Roof

How to Build Dormers

Build your dormers by first creating a small angled roof out of plywood or OSB boards before placing these on top of each other so that they are level with the rest of the home’s structure.

Make sure that you are overlapping each piece of wood by at least an inch and attach these smaller pieces to the larger ones using screws, nails, or other binding materials before attaching them to your home’s structure.

After you’ve attached all of these parts together, the last stage in understanding how to add dormers on a roof with shingles or tiles is to apply shingles or tiles over the newly formed angular roof, making it appear as if it’s part of your home’s original design.

Building Dormers In A Roof Without Shingles

You may be wondering what you can do if your roof does not have shingles or tiles on it.

You should start by making sure that the surface of your roof is flat, even, and sturdy enough for a dormer structure before you begin.

If you are unsure if your roof is strong enough, it would be best to have a contractor come out and look at the surface of your home before taking on this project.

Once you know that your roof can handle the weight of a new dormer structure, then you should start by adding plywood or OSB boards around where you want the dormer to go.

You may need more than one sheet of these boards, depending on how big your home or roof is.

Make sure that you overlap each piece by at least an inch before screwing them together and nailing them down onto the surface of your home with nails, screws, or staples so they are sturdy enough to support the weight of your dormer.

Once you have created a sturdy foundation for your roof, it is time to build up from there.

You can make several smaller angled roofs with plywood or OSB boards and place them on top of each other before attaching them to the rest of your home’s structure using screws, nails, or staples again.

Overlap each piece of wood or board by at least an inch before screwing them together and nailing them down onto the surface of your home with nails, screws, or staples so they are sturdy enough to support the weight of your dormer.

Now it is time to build up from these smaller pieces by making a larger angled roof.

You can do this by using plywood or OSB boards again and placing them on top of each other before screwing, nailing, or stapling them to the larger pieces you have already attached to your home’s structure.

Again, you should overlap each piece by at least an inch before screwing them together and nailing them down onto the surface of your home to make sure they are sturdy enough to support the weight.

The final stage in learning how to create dormers on a roof without shingles or tiles is to cover the newly constructed angled roof with shingles or tiles, making it appear as if it is part of your existing roof.

Follow these steps and you will be able to enjoy architectural interest, more living space, and an extra storage area.

If you have the proper equipment and skills, this task may be quite straightforward.

However, it’s crucial to keep in mind that adding dormers on your roof without shingles or tiles might make your house less safe for a variety of reasons, including the fact that shingles or tiles would not be able to support the weight of these additions.

Building Dormers In A Roof With Shingles Or Tiles

If you have an existing roof with shingles or tiles, then you can start by finding where your home’s current structures for dormers are located.

Use these as a reference point and mark out where to cut on the surface of your roof before taking any tools up onto it yourself to begin cutting into the surface.

Use an angle grinder with a metal saw blade to cut into the surface and create a flat, even foundation to build your dormers on.

If you do not have an angle grinder with metal saw blades, then it is best to hire someone who does to come out and help you with this project so that the foundation of each dormer is created properly.

Once you have sliced a foundation for each dormer into the roof, you can begin building them up.

You should start with a larger angled roof made from plywood or OSB boards and place these on top of each other before attaching them to your home’s structure using screws, nails, or staples again.

To support the weight of a dormer, make sure that you overlap it by at least an inch before screwing or stapling them to your surface.

Now you can build up from these smaller pieces by creating a larger angled roof made from plywood or OSB boards and placing these on top of each other before screwing, nailing, or stapling them down onto the surface of your home’s structure again.

Screw the pieces together and staple them to your dormer so they are sturdy enough to support its weight.

It’s time to finish the project and add shingles or tiles to your roof with dormers when you’ve secured all of these components together.

Placing shingles or tiles over a newly built angled roof that appears like part of your existing roof is the final stage in learning how to construct dormers on a roof with shingles or

This is the final step in learning how to build dormers on a roof with shingles or tiles: placing shingles or tiles over this newly built angular roof so that it will look like part of your home’s original design. 

This project can be fairly simple if you have the right tools and knowledge.

However, it’s essential to keep in mind that adding a dormer to your roof with shingles or tiles may make your home less safe for a variety of reasons: the roof may not be able to support the weight of shingles or tiles, you can cause more leaks by adding these new elements, and they must also be properly insulated.

Picking The Right Materials To Use

As far as the materials go, you can use a variety of them for this project depending on how long you would like it to last.

For example, plywood is commonly used because it is cheap compared to other types of wood and stainless-steel nails are also popular due to their resistance against rust.

If you plan on using these structures only for storage, then you can choose to use cheaper materials that are not as resistant against the elements.

However, if they will be exposed to rain or snow on a regular basis then it is best to invest in more expensive materials that have been treated with chemicals so that water and other liquids do not damage them over time.

Do Not Forget The Insulation…

Properly insulated so that heat does not escape through them easily.

If you plan on using these dormers only for storage, then insulation is less important but if they will be exposed to rain or snow on a regular basis then it is best to invest in more expensive materials that have been treated with chemicals so that water and other liquids do not damage them over time.

When Is It Appropriate to Start Building A Dormer?

The best time to begin building your dormers is after you finish the roofing work itself because it will be easier for a construction crew or even yourself as an individual to move around on top of the home’s structure without worrying about any of the shingles or tiles falling off.

If you do not want to wait, however, then make sure that your home is properly supported with scaffolding or stilts so that it will be easier for workers and yourself to move around up there without having to worry about too much weight on one part of this structure.

Different Types of Dormers for Your Roof

There are different types of dormers that can be built depending on what you plan to use them for, where they will be placed in your home, and how much money you would like to spend. For example:

  • Gable Dormer – this is the most common type of dormer because it adds architectural interest as well as more space to the roof itself
  • Gambrel Dormer – this type of dormer is great for adding architectural interest as well as storage space but it comes at a higher cost than other types because more materials and labor are involved in creating them.
  • Hip Roof Dormers – these structures can be very expensive depending on how big they are and where they will be placed in your home but it is also the type of dormer that adds architectural interest as well as additional space to your roof.
  • Salt Box Dormers – this structure can add extra storage or even more living area within a home without having an effect on its overall design because these structures generally do not protrude too far beyond the rest of your roof.
  • Aerodynamic Dormers – these structures are great for adding more living space without having an effect on a home’s overall design but they can be expensive depending on how big they are and where you decide to place them in your house.

How Much Does Dormers Cost?

The price of dormers can vary depending on what you plan to use them for, where they will be placed in your home, and how much money you are willing to spend.

For example: an extra bedroom would cost more than just a place to store some old books while the latter could cost more if it is located near another part of your roof or if it is a larger structure.

Aerodynamic Dormers, for example, can cost anywhere from $300 to over $1000 depending on how big they are and where you plan to place them in your home.

Gable dormers tend to be cheaper than gambrel structures because the latter requires more materials and labor during construction.

Gambrel dormers, for example, can cost $100 to more than $1000 depending on how big they are and where you plan to place them in your home.

Gable dormers tend to be cheaper because the latter requires less materials and labor during construction.

Salt box structures can also vary greatly when it comes down to price because they can be very expensive if you plan to make them as large as possible or if you want to place them at the top of your home’s roof.

Benefits of Dormers

There are many benefits of dormers such as: 

  • Adding more living space to a home 
  • Adding architectural interest and character to your roof 
  • And increasing the value of your home without having an effect on its overall design.

However, there can be problems with constructing these structures if they were not built correctly or if their materials end up deteriorating too early.

Lastly, dormers can cost anywhere from $300 to over $1000 depending on how large they are and where you plan to place them in your home.

Conclusion

By following these steps, you can build dormers in your roof.

They are great for adding more living space to a home as well as architectural interest and character to the outside of it without having an effect on its overall design or increasing how much it will cost to purchase them.

Depending on what you intend to use them for, where you want to put them in your home, and how much money you want to spend, there are numerous sorts of dormers.

Building A Dormer on Your Roof