Increase in real estate value through a roof terrace


Wouldn't it be nice to have a view over the entire city? Sounds good, but it also sounds like a lot of effort. But it's worth it!


Reading time: ca. 6:00 min.

Why you should definitely convert the roof terrace

"The apartment should definitely have a balcony." Does this sentence sound familiar? But how about even a roof terrace? Whether balcony or roof terrace, it may not make a huge difference at first glance. But the important thing is to have a place of retreat to the fresh air in the urban living space. A balcony can be beautifully prepared for this purpose. But a roof terrace has some advantages that a balcony does not have.

Because a roof terrace is often much larger than a balcony. Moreover, such a roof terrace is directly under the open sky - balconies often have another balcony above them. That's why the sunlight yield often is not particularly high. And did you know that a terrace on the roof is also called a roof garden? In fact, it is actually possible to have a soil layer on a roof terrace like in a garden, even if it is not as deep. This is also a great way to put in a plant or two. Sounds like a great outdoor retreat that is quickly accessible at any time and offers deceleration in everyday life. But how high will the costs be? Because homes are already expensive even without such a luxury – if we think of Berlin, for example.

How a roof terrace increases the value of an apartment

A penthouse apartment in Berlin really isn't anything for the small purse. Let's take a look at a sample calculation: assuming the conversion per square meter costs around 2,800 euros, the sales price of the apartment could rise to as much as 4,000 euros per square meter. But who is already with his head in the clouds now, can even go one step further – with a roof terrace. From an economic point of view, this definitely pays off: half of the roof area is added to the living space, but the development of the terrace is much more cost-effective. For a staircase, a railing, the terrace covering and the roof access hatch, about 30,000 euros would be necessary. However, this is disproportionate to the gain in attractiveness of the apartment, which is of course much higher and is clearly reflected in the sales price. With minimal use of materials and little effort, it can gain up to 95,000 euros in value – more than any other area in the house. The value of the entire real estate increases, and it also becomes more attractive to tenants and buyers.

Up on the roof – but how?

In Berlin, there is a run on penthouse apartments. Barely in the planning stage, they are already rented or sold. One possible reason for this is the building height, which the city has limited to 22 meters. All buildings that rise into the sky higher than that are considered special constructions. This creates a view over the roofs that is as unobstructed as possible – especially from a roof terrace. But how to get up to the roof terrace? Basically, there are various ways to realize the exit to the roof terrace - for example, via a staircase or a flat roof hatch, which does not require an additional housing.

Legal regulations

To convert a roof terrace, a building permit is indispensable. Therefore, a few things have to be considered before the permit can be obtained. Probably the most important component is the statics of the room below. This should be checked by a structural engineer or architect. If the flat roof does not have sufficient load-bearing capacity for a roof terrace, this can be reinforced subsequently. In addition, the sealing of the flat roof plays a major role, so that - in the event of rain for example - water does not cause damage to the structure. The rules applicable to sealing are laid down in DIN 18531 and the flat roof guideline of the Central Association of the German Roofing Trade. In addition, optimal water drainage from the floor of the roof terrace must be ensured. A gradient of 2% already allows rainwater to flow off. For the own security a sufficiently high railing is also necessary: Depending on the height of the roof terrace, it must be between 90 cm and 110 cm high.

The choice of the exit

And which exit should you choose? Preferably one that does not only please you visually, but one that is also durable and complies with current regulations. Flat roof access hatches are an elegant option. You step out into the open air like from a recumbent balcony door. If you are bound by a maximum ridge height or building height like in Berlin, which makes superstructures such as stairwells on the roof impossible, this is even the only way to produce a direct exit to the roof terrace.

Since the legislator clearly specifies here: only superstructures up to chest height are approved and the total area of the roof terrace should also have a reasonable size: 10% of the real living space should not be exceeded. That's why the space has to be well calculated to make good use of every corner of the open space. This also has to be considered when opening the roof hatch How does it open? The LAMILUX Flat Roof Access Hatch Comfort Swing corresponds exactly to this idea: Its glass element swings open hydraulically and then remains in an almost 90° open position. Its predecessors, the Flat Roof Access Hatch Comfort Solo and Duo, each have one or two glass elements that slide open sideways. But all three designs have one thing in common: they can be used even in winter under snow load, so that you can enjoy the New Year's Eve fireworks on the roof terrace. Legend has it that this is exactly how the first flat roof hatch was created at LAMILUX: A famous Hollywood director likes to spend New Year's Eve in Berlin and also wanted to enjoy the fireworks from his roof terrace there. Since staircase extensions were not possible, the architect approached LAMILUX with the task of developing a different type of access hatch. The result was the Flat Roof Exit Comfort Duo, from which the director's butler stepped out onto the roof terrace with his champagne tray on New Year's Eve. All just a fairy tale? Even if: The comfort roof hatch really do exist.