Prefabricated dormer window

Are you planning to have a dormer window installed? By opting for a prefabricated dormer window, the installation is done within one day. Read about all the options and prefabricated dormer costs in this article. That way you can be sure you are making the right choice.

What does a prefab dormer cost?

The price of a prefab dormer starts at £6,500. For that price, you have an average plastic dormer 2.5 metres wide. See the table below for an indication of the average prefab dormer prices per material type and for various sizes.

Price examples

We illustrate the above cost table using a number of situations.

Good value for money

Do you like the durability of a plastic dormer? This type of prefabricated dormer is low-maintenance and has an average lifespan of up to 50 years. You don’t have to worry about having to repair any wood rot because of the durable material. For this type of dormer you will spend around £7,000 including installation. You then have an average plastic dormer window of 3 metres wide, without extras.

Luxurious finishing

If you want to finish your prefabricated dormer window with all kinds of extra options, you will obviously be more expensive. Some people like to sleep in a room that is completely darkened. Installing shutters is then desirable. Sun blinds, ventilation grilles or other extras can also increase the total cost. This means that you pay, for example, an average of £11,000 to £15,000 for a prefab wooden dormer of 5 metres including blinds.

What does prefab mean?

Dormer windows are large structures that are placed on top of your roof. This installation can be done in two ways. A prefabricated dormer is already assembled in the factory. As a result, the ready-made dormer only needs to be lifted onto your roof using a crane. A traditional dormer is delivered in pieces and assembled on site.

What are the advantages of a prefab dormer?

Placing a dormer on your roof increases the value of your home. Not only does it create a more spacious living space, more light easily enters the room. Why choose a prefab dormer over a traditional one?

• Fast installation: as the dormer is already assembled in the factory, it only takes a few hours to install it on the day itself.
• Size: Prefab dormers are made to measure and therefore fit seamlessly on your roof
• Low noise during installation
• Lower construction waste. After all, the dormer is already assembled.
• Less chance of damage. Prefabricated dormers are lifted onto the roof with a crane. This avoids last-minute damage that can occur when lifting loose pieces up via stairs or a ladder.

When would you rather choose a traditional dormer?

A prefabricated dormer thus has many advantages. However, there are also situations when it is better to opt for a traditional dormer. Building your dormer on site is a good idea when:

• there is not enough space for a crane to lift the dormer onto the roof;
• exemption for placing a crane proves to be very expensive;
• the house is a bit older and everything is no longer perfectly straight.

Price structure of a prefab dormer

The dormer prices are structured as follows:

The largest part of the costs consists of material costs such as the dormer, window frames and extra options. You can influence the amount of this price yourself by making choices for, for example, materials, the size and any extras.

What choices affect the cost of a prefab dormer?

When you have a prefab dormer installed, there are several choices to make. These choices determine the final dormer cost. Read more below about the different choices and how they affect the total price, including:

• Material choice;
• Dimensions of your dormer window;
• Purchasing extra options.

1. Choice of material: plastic, polyester or wood

The first choice that awaits you is the type of material of your dormer. You can choose between plastic, polyester and wood.

Plastic prefab dormer: This type of material is the most commonly chosen in the Netherlands. A plastic dormer consists of a wooden basic construction and is finished with plastic. As a result, this type of dormer requires hardly any maintenance. With an average price of £7,800, this is an affordable dormer that will last a long time.

Polyester prefabricated dormer: A polyester dormer is similar to a plastic dormer in many ways. However, this type of dormer has a seamless construction and is thus almost always installed completely prefabricated. The average price tag of £8,300 pays for itself in terms of insulation and durability.

Wood prefabricated dormer window: Do you want a dormer window that is easy to maintain, with an authentic look? Having a prefab wooden dormer installed costs an average of £9,800.

2. The dimensions of your dormer

The second choice that affects the price of your new dormer is the size. Will you choose a dormer of a few metres that covers one room? Or will you choose a larger one that provides several rooms with extra space and light?

3. Additional options

In addition to the choices around the shape and look of your new dormer, there are additional options you can consider. Consider sun blinds against the sun, for example, or vents for extra ventilation options. In many cases, the dormer specialist can have these extras installed right at the time of installation.