Carport foundation: point footings, frost depth and cost

Why the foundation is on your side

We manufacture the carport at our works in Völkermarkt from hot-dip galvanised S235 JRH steel and design the whole structure for a snow load of 250 kg/m². That load — plus the wind uplift tugging at the roof in a storm — has to go somewhere in the end: through the posts into the foundations and from there into the ground. This is exactly where your part of the job begins.

The foundation cannot sensibly be prefabricated because every site is different: soil type, bearing capacity, groundwater, slope and the local frost depth decide size and depth. That is why building it lies — as is usual in the trade — with the owner or a regional construction company, while we supply the exact specification. Why snow load is the governing load case here is explained in our snow load guide.

Types of foundation compared

Four types of foundation come into question for a carport — here are their pros and cons as guide values from experience.

In practice, cast-in-place point footings prevail with our carports: one footing per post, typically around 40 × 40 cm to 50 × 50 cm in cross-section, deeper for higher loads — economical, easy to check and a clean DIY job.

Founding frost-free: depth, reinforcement, anchors

The most important point is frost-free founding. When water in the soil freezes it expands and lifts everything above the frost line, letting it sink again in spring. Over the years that movement would tip a shallow foundation and distort the structure, so the underside of the foundation is set below the local frost penetration depth.

In Austria the frost-free founding depth is, as a guide value from experience, around 80 to 100 cm, and deeper in particularly frost-prone high-altitude or cold locations. The exact value depends on region, altitude and soil type — in case of doubt a soil survey or the advice of the construction company doing the work is binding (guide values, without guarantee).

Further points that matter:

• Reinforcement: depending on foundation type and load, reinforcing steel lets the concrete take tensile forces.
• Embedding the anchors: post anchors or ground sockets must sit in the concrete in exactly the right position and at the right level — this decides whether installation fits later on.
• Level and position: all footings must be level with one another, at the correct centre distances and with the same top edge; small inaccuracies add up over the length of the carport.

From our foundation plan to the finished substructure

We supply a foundation plan with every order showing the positions, centre distances and levels of all footings for your specific model. The process is simple:

1. Foundation plan from us

   You receive the dimensioned plan — drawn so that any local construction company can work from it without queries.

2. Foundations on your side

   A regional construction company or an experienced self-builder excavates, shutters, reinforces and pours to the plan.

3. Installation by our team

   Once the concrete has cured, our own team installs the carport on the prepared foundations, within 350 km of our works.

What the carport foundation costs

There is no flat figure — the cost depends on the ground, access, type of foundation and region. As a rough, non-binding guide from experience, budget around 1,500 to 3,500 € if a regional construction company builds the foundations. If you dig and pour yourself and organise a digger, this item shrinks considerably. Only a quotation on site is binding. How the foundation fits into the overall budget is worked through in the cost guide; whether your project needs a notification or permit is covered in the guide to carport planning permission in Austria.

Ground sockets or standard anchor plates?

How the carport is connected to the foundation is your choice in the configurator — and the decision has an effect on the foundation:

• Standard anchor plates: the post stands on a visible base plate bolted to the cured foundation — robust, simple, adjustable.
• Ground sockets (Einschubhülsen): the sockets are cast into the concrete and the post later sits invisibly inside them — a particularly clean look that demands higher accuracy when pouring, because the socket position cannot be corrected afterwards.

Both variants are covered by the foundation plan. Which option suits your project you can see with a live price on the respective product page under carports.

Frequently asked questions about the carport foundation

Sources & legal basis

• ÖNORM B 1991-1-3 — Actions on structures, snow loads: Austrian national annex to Eurocode 1 (Austrian Standards, webshop search)
• EN 1991 Eurocode 1: Actions on structures — overview incl. EN 1991-1-3 snow loads (European Commission, JRC Eurocodes portal)
• RIS — consolidated state law of the Austrian provinces (Federal Chancellery)

External sources retrieved on 23 Aug 2026. Laws each in the consolidated version of the Austrian Legal Information System (RIS), standards via Austrian Standards. Information without guarantee.