What Is The Cost To Add Dormer Windows To A Roof?

What are the other cost considerations with dormer windows?

Apart from the actual cost of the dormer windows themselves, there are other expenses which are associated with fitting this type of feature to your current roofline and these include:-

•         Building permits - it doesn't matter where you live in the USA or in which state, you're more than likely to need a building permit and these can sometimes take months to be issued. Building permits also incur the levy of a fee which can typically range from around $200 to a few thousand dollars on large projects
•         Professional fees – a roof redesign normally requires the submission of drawings particularly if the project forms part of an attic upgrade
•         Window style - The window that you choose and its style, will have a big impact on the overall costs
•         Dormer window size - some window styles consist of a single pane whereas others will have a number of window panes arranged together, the style of the window and the projection of the dormer will directly impact on the costs
•         Roof upgrades – often dormer windows are part of a project to convert roof space for accommodation or to upgrade living space that is already there, dormer windows are therefore not usually the only part of the cost. Some homeowners combine a dormer window project with a roof re-model or refurbishment project

What is a dormer window?

The word ‘dormer’ comes from the French verb, ‘dormir’, meaning to sleep, which is a style of window always associated with the upper levels of accommodation within the property.

A dormer window is a vertical unit with its own integral roof which is partly positioned within the slope of the existing roof. They are popular for people seeking to convert their attics and who are restricted by not being able to extend their home sideways or to the rear. Dormer windows can come in all shapes and sizes.

Why add dormer windows?

The main reason for adding dormer windows to a roof is in order to create light for an attic conversion. This may be an attic conversion that is already in place but which lacks light and roof height or it could be a completely new design and remodel which is being planned alongside a new roof.

Dormer windows can be a difficult design to get right; the style of the roof, the roofline and the way in which the dormer windows impact on the house as it sits with other properties, will need to be carefully considered by the designer or architect. Dormer windows which look awkward or clumsy or which are not proportional to the house will not enhance either its appearance or uplift its value.

Badly designed dormer windows can ruin the entire look of a property and will always have a negative impact on its value and curb appeal even if they do the required job of adding light and ventilation to the roof space.

What are the main costs associated with dormer windows?

The main costs with dormer windows are not just the windows themselves but the actual cost of the attic conversion and much of this will depend upon what type of accommodation you are seeking to create. Adding bathrooms or self-contained units with kitchens will always cost much more than just extra bedroom accommodation.

Different types of dormer window

Whichever type of dormer you choose will dramatically impact on the cost and there are many different types of dormer that you can select for your home. The most common type of dormer window is called a gable fronted dormer and this usually has a simple pitched roof which slopes down to either side creating a cottage type appearance. A vertical frame supports the planes and forms a triangular section below the roofline.

A shed dormer window features a sloped single flat roof in the same direction of the roofline but at a shallower angle. There is a popular design called a Nantucket dormer window style which is a shed dormer connecting two gable dormers.

A hip roof dormer slopes on three planes and converges at one point over the window pane whereas a Gambrel dormer has a gable at the peak of the roof but two steeper slopes on the sides like a barn roof.

An eyebrow window dormer has a curved roof and no sides and creates an eyebrow effect which is why these roofs are sometimes called an eyelid dormer. The other two types of dormer window are a bonnet dormer which has straight walls with a curved roof and a wall dormer which features a window situated directly above the exterior wall instead of in the middle of the roof.

The cost of shed dormers versus gable dormers

Gable dormers are also known as doghouse or kennel dormers and are usually best suited to homes with a steep roof pitch and an angled roof. Gable dormers are cost-effective and attractive and are usually one of the more budget-friendly dormer window options.

Shed dormers are a bigger investment but they do offer increased square footage and are one of the best ways to add headroom and space to smaller homes.

A Nantucket dormer is a combination of a shed and a Gable dormer and is created by erecting two gable dormers and connecting them with a shed dormer.

What are the pros and cons of dormer windows?

There is no doubt about it, dormer windows are a highly desirable window style with great curb appeal and they can completely revolutionise an attic conversion, adding floor space ventilation and natural daylight to what can be an otherwise unappealing space. However, these windows are expensive and inconvenient to install and despite their numerous advantages, can be off putting for some homeowners. Here are some of the pros and cons associated with installing dormer windows which might help you make a decision:-

Advantages

•         Internal lighting - the attic or loft conversion will be much brighter and will benefit from natural light and also views which can become a real feature depending on your location. Natural light has plenty of proven health benefits
•         Increased space – dormer windows add extra space in the conversion and make it possible to have tall furniture
•         Ventilation - dormer windows that can be opened will allow fresh air to circulate around the room and solve a number of the ventilation problems associated with attic conversions
•         Aesthetic appeal - Dormer windows which are well designed and proportionate to the size of the property can really improve curb appeal and add character and style to what can otherwise be a plain roof

Disadvantages

•         Roofing eaks - unless dormer windows are very well installed, they can be vulnerable to leaking as essentially they are built into the main roof structure so dormer windows do create a weak point for the ingress of water. Their integrity should be checked as part of an annual roof inspection
•         Cleaning - cleaning dormer windows can be challenging unless they are able to be completely opened and rotated by 360 degrees. Some dormer windows can't be opened at all
•         Cost – dormer windows are expensive regardless of the style and type you choose as most of the cost relates to the installation

Finding the right roofing contractor

Installing dormer windows is not an insignificant cost and often forms part of a larger project. The roofing element of the plans needs to be undertaken by a professional roofing contractor following a thorough inspection of the existing roof (if it is not to be renewed) and working to drawings and plans usually provided by an architect or surveyor. If you are replacing skylights with dormers then you may be able to just work with your roofer on this project.

If you need to find a roofing contractor then try to go word of mouth and get a personal recommendation. Ask friends, family or neighbours for info or you could consider putting a post on social media groups in your area to see if you can find someone.

Installing dormers is a professional job so you want to avoid the lower end of the market and firms which tend to just specialise in roof repairs rather than more substantial roofing projects.

Questions to ask your roofing contractor?

•         Is the roof suitable for dormer windows?
•         How many does he recommend?
•         What is the best style for your needs and to suit the property?
•         What are the different types of glass available in terms of eco-friendly and self-cleaning options?
•         How long will it take to install them?
•         Does the roof need any upgrading or repair in the areas where the windows will go?
•         What guarantees and warranties are offered for workmanship and products?
•         How long has the company been in business?
•         Are there previous customers you can speak to who will act as references?

Are there any grants available to help with the cost of dormer windows?

Most roofing grants are aimed at repair or renewal to keep homes watertight; dormer windows tend to be bracketed in the category of home improvement and would not be viewed as an essential roofing need unless they were pre-existing, old and letting in water. Adding new dormer windows is a matter of preference and usually the homeowner would have to bear all of the cost himself.