Advice on solar carport & foundation planning: Cost factor of ground foundation for solar carports

Quick assembly and easy assembly, with these attributes you can find many offers on the topic of solar carports. But that's just the tip of the iceberg. For competitive reasons, the price usually does not include the costs for ground foundations and, for some types of solar carports, the important support compensation for the statics. This makes it difficult to make a direct comparison.

Ground work is the big unknown when it comes to solar carports. Strip foundations are a common type of foundation. So they take the entire weight of buildings and pass it on to the ground. This is hard work and sometimes requires heavy equipment. Therefore, very special properties are required for strip foundations. In order for a building to be stable later, the ground must be load-bearing.

In order to achieve a larger load distribution area between the wall and the ground, the strip foundation is usually made wider than the upright wall. Strip foundations must be carefully planned and constructed. What you save in the process will have a huge impact later on and endanger the entire construction project. Of course, this also depends on the condition and type of soil. Every strip foundation needs a dense and stable soil. If the ground is soft, the foundation must be designed over a large area in order to better distribute the load to the ground so that the building does not sink.

It's similar and yet a little different with solar carports. Depending on the type of support of the solar roof substructure, support compensation on the ground is necessary. Depending on the beam balance and soil statics, a strip foundation may no longer be sufficient, so a concrete slab must be used.

What may not be so noticeable with single and double carports will become a major financial issue with large solar carport systems.

Point foundations are therefore not only the more cost-effective choice, but also the simpler and more flexible construction method for solar carports. However, point foundations are not possible or applicable for solar carports with support compensation.

Point foundations are more fault tolerant and easier to adjust. They can also be individually adapted to the respective floor conditions at any time. The 4-column technology of the modular solar carport system in question, the point foundation or floor slab application (depending on the existing floor sealing) has proven to be very flexible and usable, especially in the case of an arched row or sloping parking spaces for solar carports proven.

No question, all solar carports must meet the static requirements. And yet there are differences when it comes to vehicle and parking frequency. There is undoubtedly a difference between single and double carports in private households and large solar carport systems with high visitor frequency, such as: B. in shopping centers, company parking lots and others.

The high volume of driving and parking therefore requires solid planning in the foundation so that the first restoration measures do not have to be initiated after just a few years. Savings are often made at the wrong end here.

4-pillar solar carport system with 2-pillars (4+2+) expandability per double parking space

Modular solar carport system with 4+ 2+ columns, round – Image: Xpert.Digital

The cost-effective point foundation is only possible with the 4-column technology. It is the first choice for secure installation compared to slab or strip foundations. In addition, only a small amount of building material is required here.

In addition to the simple modular expandability of the 4-column construction with only 2 pillars (4+2+ technology/system) per additional parking unit, this technology can also be used for diagonally offset open parking areas. Furthermore, 4-column solar carport substructures are lighter and individually adaptable, even for curved parking lot sections, in contrast to the other constructions.

With base plate, support shoe or post shoe for already sealed surfaces

Modular solar carport system with base plate – Image: Xpert.Digital

Depending on the nature of the ground in the already sealed areas, it is also possible to screw the post bases to the ground. This means that no further ground work is necessary and underground pipes are not affected.

Because the 4-column technology also allows screwing to the ground, they are ideal for parks with free, uncovered and drivable upper deck or roof parking spaces!

Everything from a single source, specially designed for solar solutions for large parking areas. You refinance or counterfinance into the future with your own electricity generation.

Advice and solutions can be found here 👈🏻

Advice and planning including a non-binding cost estimate. We bring you together with strong photovoltaic partners.

Advice and solutions can be found here 👈🏻

We are positioned across regions in German-speaking countries. We have reliable partners who advise you and implement your wishes.

Get in touch with us 👈🏻

T-beam solar carport

Solar carport with T-beam – Image: Xpert.Digital

Depending on the statics, a support compensation on the ground for the solar roof substructure of the T-beam must be taken into account. A ground foundation is necessary for T-beams. Depending on the nature of the ground, a concrete slab may also be essential, which requires heavy equipment for assembly and alignment.

Solar carport with offset T-beam

Solar carport with offset T-beam – Image: Xpert.Digital

Subsequent adjustments and corrections are very difficult and some work steps that have already been carried out have to be undone, which affects the costs. Arranging solar carports with slight curves or slanted parking spaces is not possible with this system.

Construction changes due to “unforeseen” changes in soil properties can also subsequently increase costs, which in turn raises the suspicion that a low price was “deliberately” set in the offer phase in order to gain a competitive advantage. With point foundations, such “unforeseen” changes are not serious because you can react flexibly.

V-beam solar carport – Image: Xpert.Digital

Depending on the statics, support compensation on the ground for the solar roof substructure of the V-beam must be taken into account. A ground foundation is necessary for V-beams. Depending on the nature of the ground, a concrete slab may also be essential, which requires heavy equipment for assembly and alignment.

V-beam solar carport with supporting wall – Image: Xpert.Digital

A solar carport with a concrete supporting wall on the sides is considered a particularly robust construction. The robustness and weather resistance of concrete retaining walls with foundations below the ground (strip foundations) come at a price. This is hard work and can only be carried out with heavy equipment.

Compared to concrete buildings, damage to concrete retaining walls, material-related cracks or external force are correspondingly higher, which can no longer prevent the ingress of moisture during the next rainy period and damage the material.

In comparison to the 4-column construction, the risk of contamination with concrete retaining walls due to environmental and external influences is immensely higher. Be it through illegal spraying activities by third parties or other influences. Even small dirt blown in by the wind cannot blow away compared to the 4-pillar construction, but remains stuck to the supporting walls, so that all parking areas have to be “swept” from time to time.

Likewise, the indestructibility of the retaining walls in the event of collisions is only limited. Depending on the type of collision, it can also lead to instability of the system; due to the heavy construction, repair work is only possible with heavy equipment and involves much higher maintenance costs than with another solar carport system.

Collision protection posts (with point foundations) on the respective solar carport systems have proven to be much more cost-effective, unlike the systems with concrete supporting walls on the sides.

TV carrier solar carport with supporting wall – Image: Xpert.Digital

Another option is to reduce the size of the retaining wall and move it to the end of the parking area. This means that the driver can get in and out of the car without any problems if they park skillfully. Otherwise, the above points remain the same.

Solar carports sensitive entry zones – Image: Xpert.Digital

Suitable for:

• The parking space requirement, the solar requirement, types of parking spaces and the solar carport strategy for open parking spaces
• Solar carports where there is no longer a standard - the optimal solution for every challenge with solar roofing for open parking spaces

But it can also be smarter : the combination of wooden construction and the solar carport 4-pillar technology, where the supports are made of steel. In the upper area, directly under the solar modules, the wooden substructure for solar modules is protected from the weather, while the support columns are still made of steel, like all other large solar carport systems. With this method, the wood used requires virtually no further treatment against the effects of the weather, even over decades.

Suitable for:

• Architects love them: Aesthetic variety with semi-transparent double-glass solar modules for solar carports and terraces

This combination also saves a lot more steel, which is reflected in the price.

Another important aspect comes when it comes to aesthetics and appearance.

The combination of wood and steel with a translucent roof using semi-transparent double glass modules not only refines the parking area itself, but also has a major positive impact on people and the environment.

We know this from the construction industry. There are different ways to keep people from certain areas and only allow them to come if absolutely necessary. On the other hand, there are many areas that thrive on high customer frequency, such as: B. Shopping center. The competition is great. Therefore, it is particularly important here to set accents that attract people and where they feel comfortable.