Do I Need A Foundation For A Carport?

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A carport can be the ideal alternative when a garage isn’t an option or you just prefer the ease of the semi-open space. However, choosing a carport kit in favour of building a garage doesn’t mean there isn’t some preparation to undertake beforehand, regardless of whether you’re choosing a rustic oak aesthetic or a modern aluminium design. 

Adding additional space to the home allows for a multitude of benefits, and carports are an affordable way of acquiring a sheltered parking spot without planning permission in most instances. However, some considerations need to be made before you build a carport, especially when determining the type of foundation to use. 

Choosing the Foundation

When searching for advice regarding foundations, many can find the feedback conflicting. This is because people have preferences regarding bases, and the best options often depend on the circumstances, such as the type of vehicle being stored as well as the ground conditions. 


One of the most common materials used for carports is concrete and for good reason. As well as being dependable and robust, it also provides plenty of longevity. The base can be fitted using heavy-duty bolts and anchors and is often preferred by those wanting to protect their car in adverse weather conditions. 

However, those with a tight budget may find concrete too expensive for their project. Fortunately, there are other options available, but some may need more maintenance than others. 


Asphalt (or Tarmac as often referred to) can be a suitable surface to bolt a carport to, BUT it is imperative the correct ground anchors are used.

If you don’t use the correct fixings, it is highly likely they will pull out from the ground as soon as a decent gust of wind gets hold of the carport, causing no end of damage to itself and its surroundings.

Search the internet for ‘Asphalt Anchors‘ and use a reputable brand suitable for the application intended.

If the Asphalt is degraded and breaking up, it is worth digging 30cm diameter holes with a minimum depth of 50cm where the carport legs meet the floor, and pour concrete piers into the ground. You can mix some black or grey cement dye into the top 5cm of concrete so that it matches the colour of the asphalt to a certain degree.


As people have different preferences regarding the ground coverings where the installation of a carport is to be, gravel may be your base of choice.

Now obviously, you cannot fix a carport directly into a gravel base, so concrete piers are recommended. Dig the holes approximately 30cm diameter and a minimum of 50cm deep. Go deeper for larger carports, and much deeper and wider for cantilever carports where all the load bearing is on two legs of the canopy only.

Keep the concrete level just below the surface of the finished height of the gravel so you can cover the concrete with gravel when the carport is installed for a more pleasing look

Timber Decking 

Canopies can be fixed to timber provided that the correct fixings are used. We recommend heavy duty coach bolts which are fixed through the timber decking and into the joists below.

Remember, a carport will act as a giant sail in windy conditions and must be secured properly to its foundation.

Setting Out The Base 

Mark the area for the planned installation with stakes ensuring the area is secured away from other people for safety. After the stakes have been placed in the ground in relation to the position of the carport legs, dig holes no less than 30cm diameter and 50cm deep. This not only creates a strong foundation, but allows space to make adjustment of the legs when it comes to installing the carport.

Ensure each hole is filled to the same level in case the ground is uneven. Create a wet mix concrete 1 part cement to 2 parts sand to 4 parts aggregates and let set for a minimum of 5 days so the ground anchors will hold.

If you are concreting the whole base area, it is advisable to use a readymix company to deliver the concrete premixed for you.

Is Mesh Reinforcement Always Needed When You Build a Carport Foundation  

Although a carport must look the part, it is important to support the structure correctly.

Whether you’re building a carport as a do-it-yourself project or enlisting the services of a professional, a sturdy foundation is essential. If the right support isn’t in place, then the space could become uneven as the base may crack and it will not be able to withstand the weight of the vehicle being stored. 

When reinforcing concrete, there are a couple of options available. Two of the most common are steel mesh and rebar, or fibre mesh. For major building works steel mesh and rebar are commonly used, where the mesh covers the whole area of the slab and the rebars are fitted around the edge of the platform. 

In our case, fibre mesh is the better alternative. It’s much cheaper that steel, and perfect for slab applications such as this. Fibre mesh is not required for foundations where you are just digging holes as in the gravel base example above.

DIY Or Professional to Build a Foundation For A Carport? 

That all depends on your level of competency in building projects.

It’s not difficult to either lay a full slab of concrete or to dig holes and lay individual foundations, but there is a level of skill required.

If you’ve not done it before, I’d suggest you leave it to the experts. An experienced builder can help you create a foundation suitable for its requirements although the labour cost may mean that the cost to lay the base is close to the cost of the carport itself.

If you decide to do it yourself, Nucrete support their customers with quality tech support whenever needed for their carport or groundwork requirements. We have experienced technicians on hand that can answer any questions you have regarding the setting out, or building of the foundation or carport itself.  Give us a call anytime.