When to retrofit a solar system and when not to?

The most important answer first: Retrofitting a solar system to existing buildings is possible at any time. Even if the effort for the realization seems to be very high, photovoltaic retrofitting has become a standard procedure that solar experts deal with on a daily basis. The actual procedure works, as far as planning and installation are concerned, in a similar way as for a new building.

The decisive factor for retrofitting a solar system is the possible electricity yield. The retrofit is only worthwhile if the installed system receives sufficient sunlight over the course of the year. The basis for such a consideration is a demand calculation. This takes into account the previous electricity consumption in kilowatt hours and serves to determine how large the photovoltaic system on the roof must be dimensioned.

If the building roof is shaded for large parts of the day due to an unfavorable location between buildings or trees, retrofitting a PV system is not worthwhile. This also applies if the roof surfaces are unfavorably oriented or too steep. Since slope and orientation are locally very individual, the analysis of a solar professional is essential. However, the following information can provide initial indications.

Retrofit criteria

Here are the criteria for when you can retrofit your roof with a solar system without any problems, in brief:

• Feasible with standard procedures by experts
• Works similar to new construction
• Worthwhile when there is enough sunlight
• Carry out requirements calculation

What requirements should my roof have?

A roof area that is as large as possible and faces south is ideal for retrofitting a PV system. However, roofs with an east-west orientation also have the potential to produce large amounts of electricity. However, solar experts like EWE-Solar can also plan systems in such a way that an effective power supply is possible through simultaneous occupancy in east-west as well as north orientation.

If possible, the roof surfaces should not be shaded or should not be exposed to shade for as much of the day as possible. An ideal electricity yield during the course of the day can be achieved with roofs that have an inclination between approx. 30 and 40 degrees.

Requirements of my roof

What should my roof optimally bring?

• Large roof area
• Optimal: orientation to the south
• All right: east-west orientation
• No shading
• Inclination between 30 and 40 degrees

What do I always have to consider when retrofitting?

Retrofitting a solar system is an investment that will only pay off in the medium or long term. Accordingly, it is important that you rely on solid financing for the project. It takes several years until the point is reached where the saved energy costs exceed the investment sum including interest. When it comes to retrofitting a PV system, false economy is also out of place. Do not make the mistake of planning too tightly and without reserves. A slightly larger sized system is always the better option. It ensures that the supply is covered even if the energy demand increases in the future.

What if you decide to buy a sauna or an electric vehicle? If the system is too small, you would once again be dependent on mains electricity. The same applies to making the most of low solar radiation, e.g. in autumn and winter. The larger the system, the more energy it can generate even in poor conditions.

Tip: Installing a home storage system (home battery) makes it possible to store electrical energy that is currently being generated but not consumed. This is then available, for example, at night or on dark days.

More tips for retrofitting solar systems

1. mounting system: Each roof and each location offer different conditions for the roof installation. Accordingly, ask your installer for advice on the ideal mounting system. This should be adapted to the weather and weather conditions (wind and snow load).

2. caution: scaffolding is required: solar systems are usually installed at heights of more than 1.5 meters above ground level. Please note that the law requires the erection of scaffolding in this case.

3. timing: You can certainly have a PV system retrofitted at any time. However, since the area around the house is at least temporarily transformed into a construction site, the ideal time is when the roof is due for renovation anyway. This way, the solar installer can also use the standing scaffolding.

4. use additional space: The solar modules do not necessarily all have to be mounted on the roof. If there is not enough space for the desired dimensions, additional solar modules can also be installed on garages, canopies, etc.

5. compare offers: Retrofitting a PV system is a very individual matter. Accordingly, it is advisable to seek advice from several specialist companies and to submit an offer. Often, not only the prices differ, but also the individual solutions.

Conclusion: Is retrofitting solar systems worth it?

Retrofitting a PV system is easily possible on most roofs. Even in the case of shading or unfavorable roof orientations, PV experts can make the most of the situation. This means that nothing stands in the way of the dream of low-cost electricity from one’s own roof, even for owners of existing properties. But that’s not all: depending on the type and dimensions of the PV system, attractive subsidies are available.

Old properties: Aging properties

The age of a property is a decisive factor when it comes to buying a property. But what are the differences and defects depending on the age and year of construction of a property? Is it worth investing in an aging house or apartment?

Purchase price and return

Older properties often have a lower purchase price and thus lower ancillary purchase costs. Thus, the return is also significantly higher than for newer houses with a high purchase price.

Maintenance costs and defects

Due to the age of the property, the running costs are significantly higher. Different years of construction have different defects, which should be taken into account during the technical inspection of a property. The better the location in which you buy, the older a property may be.

Advantages and disadvantages

Here are briefly summarized the advantages and disadvantages of buying an old property!

Advantages:

• Favorable purchase price, better return
• Costs are calculable if defects are known
• Location in grown infrastructure

Disadvantages:

• Higher costs for maintenance
• Possible hidden defects

Existing real estate: typical defects

Among the disadvantages of buying existing real estate is the occurrence of possible defects. Generally, these include mold, water damage, vermin infestation or dry rot.

Here is a brief overview of typical damage and defects:

• Building fabric: cracks in the plaster or masonry, mold
• Building services: insulation of water pipes, sometimes still lead pipe in use
• Electrical engineering: Too few sockets in the rooms or cables too thin according to old standards
• Roof: missing and slipped roof tiles (moisture penetrates) or mold infestation
• Leaky: windows, basement and roof

Checklist 1900-1999: Defects, Damage & Co.

Here you can find a list of old buildings from 1900 to 1999 and what typical defects and damages they have.

Existing properties up to 1900

Properties built before 1900 are now over 120 years old! It should come as no surprise that these properties have defects. Weather, weather and Co. have here a large influence. But also the electrical and sanitary systems can be outdated and need to be replaced urgently. Here you can find an overview of the possible defects:

Facade, insulation, roof and basement:

• Cracks in plaster and masonry
• Non-existent thermal insulation (subject of energy efficiency)
• Single glazed windows
• No sound insulation

Plumbing and electrical:

• Damp basements and attics
• Lead pipes as water supply (No longer permitted!)
• Obsolete electronic system

Existing real estate 1900 – 1939

Properties in these years also have certain defects. Here is an overview.

• Missing underlays in the roof
• Dampness in the roof & basement
• Sponge infestation of wooden beams in ceilings
• Defects of the outer walls due to too thin constructions
• Condensation problems and mold
• Lack of fire protection
• Lead pipes as water pipe

Existing real estate 1939 – 1945

These years are considered very eventful in Germany. Political changes and the Second World War took their toll on the building stock, and as a result very little new construction took place.

Overview of deficiencies due to the Second World War:

• Severe shortage of building materials
• Construction waste and miscellaneous became building material
• Pest infestation due to wrong building material
• Fast building can also cause static problems
• Cracks in the plaster or masonry
• Exterior and interior, thin walls
• Leaking gas pipes
• Lack of fire protection

Existing real estate 1945 – 1959

Properties built in the post-war period from 1945 to 1959 also have some defects due to Germany’s difficult situation.

• Lead pipes still in use (increasingly steel pipes)
• Use of questionable building materials such as asbestos and lead paint
• Lack of fire protection (fire department access, fire doors)
• Gas pipes leaking
• Vermin in the wooden ceilings
• Poor sound insulation (thin walls and wooden floors)
• Here too, cracks in the plaster or masonry

Portfolio properties 1959 – 1969

While property defect lists were relatively long before 1960, the items on the checklist already shorten considerably for post-1960 construction. Here is a brief overview:

• Single glazing
• Building materials of concern (parquet adhesives containing tar)
• Insulation harmful to health (fibers too short)
• Roof trusses not insulated
• Concrete damage to balconies and loggias

Portfolio properties 1969 – 1979

From 1970 onwards, the introduction of soundproofing and insulation requirements allowed even more deficiencies to be crossed off the list. There was also a revolution in the subject of water pipes and building efficiency

Here is the brief overview of remaining deficiencies:

• Concrete as a building material with difficulties in cold / moisture
• Already, often in need of renovation (balconies, old water pipes, heating systems).
• Parquet adhesives containing tar were still in use
• Central heating (year of construction before ’85 must be replaced)

Portfolio properties 1979 – 1999

Here you can often find a very solid stock of used building materials that do not need to be replaced.

Here are just the few defects that are present:

• Connections and terminations for flat roof
• Central heating (year of construction before ’85 must be replaced)
• Upcoming maintenance in view
• Weak insulation

More on the subject of construction defects/ Immobilien-Erfahrung.de

The next step: maximum size of your property

How big should my first condo be? Micro-apartment, 2, 3 or even more rooms? This question is answered here by comparing living space for owner-occupancy and capital investment. In general, the number of square meters and the room layout are particularly important. Everything else, you will learn here!

Terrace design: planning, alignment and the right look

If you want to plan a terrace, there are a few aspects you should consider in order to make it especially cosy and homely. Especially in summer or during the first warm spring days of the year, you can’t get enough of the benefits of a terrace. It expands your living space and moves it outside. With the right planning, an ideal orientation and the right look, you can make a terrace your personal oasis in your home. We show you what to look out for!

Tip! Popular and luxurious interior brands and furniture are presented here: Interior Brands XXL!

Planning your dream terrace: find inspiration and the right furnishings

First of all, you should start by gathering inspiration. Ask yourself what you want to use the terrace for and what all needs to be on it. A barbecue, a large dining table, loungers or play facilities for the children? Know what you want and start planning. Look for furnishing styles that you like and collect pictures of furniture or decorative items that should not be missing on your dream terrace. Make a list or a mood board with your personal furnishing styles. You’re sure to find the right inspiration in our Luxxu or Minotti articles.

Orientation & size: north, east, south or west

You should also plan according to your wishes when it comes to orientation. Do you love to spend the afternoons in the sun and get a nice tan? Then you should orient your terrace to the south. Do you prefer a warm evening light to watch the sunset? Then a west orientation is ideal. It is also not uncommon to build a second terrace to take advantage of more hours of sunlight. We recommend that you lay out the various potential sites before building, testing everything out and paying attention to details such as trees or views.

The size of the terrace should also be adapted exactly to your wishes and requirements. It makes little sense to fill up a small terrace with lots of furniture and decorative items. Think about which elements should not be missing and adjust the size accordingly.

Look & design of the terrace: style rather natural or modern?

The preferred patio look is the nature look. You want to try to capture nature and expand your living space that way. Suitable for this are many plants, matching furniture and a terrace floor of natural stone or wood. Likewise, a water source, such as a landscaped pond, will bring tranquility and have a naturally relaxing effect on you. Also choose large doors and windows in your house that face the garden and use similar flooring on the terrace as in the living room. This will expand your space and bring nature into your home.

Video: Modern Garden and Patio Design – Go for Minimalism

Looking for more inspiration for your patio and want to choose the right look? Here you’ll find some tips and design styles to make your patio extra special. The trend is towards minimalism and this can be emphasised with the right water features and lighting.

Tip. Also check out our article on minimalist furnishings.

Flooring: tiles, slabs or floorboards? Comparison

Once you decide to build a patio and start planning, the first thing you should consider is the floor. You will be offered a wide range of different materials, colours and patterns, all of which have their advantages and disadvantages. We will introduce you to a few groups here, so you can find the ideal flooring for your dream patio. Whether tiles, natural stone, wood or WPC. We will support you in your decision.

Natural wood: warm, homely and natural- the classic

Wooden decking is very popular for terraces and for good reason. Wood is warm and homely and creates a natural and cosy oasis on a terrace. Nevertheless, you should pay attention to the quality when choosing. The wood must be weatherproof and durable. A hard wood is ideal. Oak or ash are particularly popular, as they are considered to be resistant and stable. A cheaper alternative would be pine or Douglas fir.

WPC: Wood Plastic Composite- low-maintenance alternative for outdoors

WPC is the easier-care version of natural wood and a combination of plastic and wood fibres. Therefore, this variant also combines the advantages of both materials. The surface resembles that of natural wood and is hardly distinguishable from them. WPC is particularly durable, easy to maintain and practical. It can be perfectly cut for your terrace but also for the balcony and is a very good alternative to natural wood.

Natural stone, concrete, tiles: easy to clean and simple

Tiles, concrete and natural floors are above all easy to maintain, resistant and durable. Therefore, they are the classic alternative to natural wood. They are easy to clean and many people find the stones even more beautiful after a few years, when they are darker and more adapted to nature. It is also very nice to have the stone continue into the living space on the patio, creating a natural transition. Note, however, that the effort to lay a natural stone is higher and you should always consult a garden specialist.

Patio furniture: Sofa, Chairs, Tables & Loungers – Materials

Patio furniture transforms your patio into something cozy and provides seating for different occasions. Find a matching table and chairs to host your next barbecue. Or invest in a daybed and create your own personal outdoor relaxation space. In the following we will introduce you to different materials of patio furniture, so that you can make the right choice in the end. Because the outdoor furniture must be one thing above all. High quality, durable and sophisticated design.

Tip. Our article on outdoor furniture might also be helpful for your patio planning: Garden Furniture.

Furniture made of polyrattan: high quality and easy to clean

Patio furniture made of polyrattan is particularly high quality and easy to clean. The material consists of synthetic fibers and offers a high seating comfort. A big advantage of this furniture is the surface. This does not fade in strong sunlight and water drops roll off the surface. If you want to clean the furniture, a damp cloth or the garden hose is sufficient. The upholstery and covers are also weatherproof and repel moisture. Nevertheless, you should make sure to cover them and the furniture in winter and move them to a dry place. A garage, cellar or garden shed is ideal for this.

Furniture made of wood: the classic with nature charm

If you decide to use wood as a material, you definitely won’t go wrong. Wooden patio furniture is a classic. They are durable and also easy to maintain. Usually tropical woods such as teak, mahogany or meranite are used, but these are now combined with other materials such as synthetics, stainless steel or aluminium. This increases the quality of the furniture. However, if you want your wooden furniture to last for a long time, you will have to repaint and varnish it every few years. Due to the settled dirt and moisture, it is recommended to paint the furniture with varnish or paint.

Metal furniture: particularly durable and modern

Aluminum patio furniture is also very popular because it is often available in different colors and requires little maintenance. If you choose an aluminium seating group, you can move it easily because the material is very light. In addition, the furniture adds a lot of cheerfulness to your patio because of its beautiful and bright colours. Another advantage is the price of aluminium furniture, which is usually comparatively low.

Patio furniture made of iron, on the other hand, is rather heavy but all the more durable. You will have to do more maintenance, but you will get more use out of the furniture. If you clean and paint it regularly, you won’t have to worry about new furniture for the rest of your life.

Awnings for your terraces: Beach club with privacy screen

A sun sail is the absolute must-have for an exclusive and luxurious garden. If you have already chosen the right pieces of furniture, a sun sail on your terrace can’t be missing. Besides the fact that it provides shade on hot days and, unlike an umbrella, does not require any space, a sun sail has the charm of a resort or beach club. So create your own exclusive and private space on your terrace.

Size and shape: the right dimensions for your terrace

The size and shape of a sun sail can vary depending on use. If you have a small terrace, for example, a triangular, smaller sun sail is suitable. This will provide you with plenty of shade on hot days, but you will still have a few rays of sun available. For a larger terrace, on the other hand, a rectangular or trapezoidal sun sail is suitable. These can shade large areas particularly well and you also have the option of covering parts of the green area.

Materials: high quality, robust and protective

The material of a sun sail should above all be wind and waterproof. Therefore, most sails are made of synthetic fiber and additionally impregnated. You should also make sure that the sail meets the UV standard, as it should not only provide shade, but also protect you from harmful UV rays. Many newer sails are available with a net-like, open fabric. These provide less protection from the sun’s rays, but are less susceptible to storm damage and the attachments are less stressed in wind or thunderstorms.

Electric awnings: for more luxury and comfort

Electronic awnings offer luxury and comfort above all. As soon as the summer is over or a summer storm announces itself, you are forced to take down your awning, which is a lot of work in addition to the time involved and cannot be done alone. If you want to save yourself this effort, you have the option of using an electronic sun awning. This is automatically retracted during a thunderstorm and is much more comfortable than a conventional one. Treat yourself to this luxury and invest in an electronic sun awning.

Terrace roofing: modern, comfortable and robust

You are looking for an alternative to an awning and want to have a fixed and built-in canopy. Then you should get an advanced, comfortable and luxurious patio cover. In this video you will see how easy it is to change the functions of such an enclosure and how modern it is.

Roof terrace: luxury feeling with panoramic view

A roof terrace is exclusive and that’s how it should be designed. Most of the time you have a view over the city and a lot of space, which you can furnish and decorate as you like. There are different ways you can use your roof terrace. Maybe as a place of tranquility, away from the hustle and bustle of the city and as your personal oasis? Or rather as a place for exclusive parties, cocktail evenings with friends including a panoramic view? No matter what you decide or whether you want to create a combination of both uses, here you will find the right tips and interior design styles.

Furniture on the roof terrace: lounge, daybeds or Hollywood swing

You should go for luxurious furniture when furnishing a roof terrace. Opt for large lounge furniture, hammocks, daybeds or a Hollywood swing. During the day you can enjoy the sun’s rays there and at night the matching seating options ensure a relaxed mood. The absolute it-piece should always be a white sun sail. It gives the ultimate luxury character, as it is reminiscent of exclusive resorts. But the functionality of the sail is also very advantageous. On the rooftop terrace, there are usually no shade options and thus you would create a privacy and sun protection. Build your personal and exclusive beach club for relaxing days and exciting nights.

Are you interested in luxurious furnishings and high-end furniture? Then check out our luxury interior guide for the right inspiration!

Water sources, plants & lighting: creating the right atmosphere

To create the right atmosphere during the day and at night, you can help with some elements. Water sources in particular are invigorating during the day and cool you down in the hot sun. Water is calming and can be used in the form of a fountain or a pond. Especially when the sun disappears and night falls, directed light sources offer a very special atmosphere. Use different, small light areas in the form of fire bowls, fairy lights or lanterns. Plants also have a very calming and natural effect on your roof terrace. With the right layout, these can also be used as windbreaks or privacy screens.

Whirlpool or roof garden: luxury on your roof terrace

Of course, the perfect luxury items can’t be missing from your dream roof terrace. To create an exclusive space, you should invest some money in making your terrace extraordinary. Buy a hot tub or an outdoor shower to have your own private space above the rooftops. Or build a rooftop garden with real grass to create an oasis of relaxation and tranquility.

Tips for the perfect interior: luxury inventory

In summary, there are five important tips you should keep in mind when setting up your rooftop patio:

• Buy high quality and luxurious furniture as a suitable seating option
• Use the space and create the right division for the day and night
• Invest in a sun sail for the beach club flair
• Create atmosphere with light, water or plants
• Invest in luxury items like a hot tub or a rooftop garden