What kind of base do I need for a Garden Room?

At Gillies and Mackay our buildings are fairly HEFTY, to say the least. So, when we’re thinking about the foundations for a Garden Room, we need to appreciate that the weight has a huge influence over what kind of base we should construct.

Typically a Garden Room will weigh over 2 tonnes. We would normally recommend a concrete plinth built to a specific specification. However, new technologies, such as ground screws, are offering a more eco-friendly alternative.

Let’s have a look at both options…

Please note: We highly advise you obtain landscaper/construction quotes for base work before ordering your Gillies and Mackay building to obtain a full and clear picture of project costs.

Concrete Plinth

For years we’ve been involved with specifying a structure for the concrete bases required to support our buildings. Most commonly for our Garden Rooms and Garages.

Let’s call it ‘clever-clogs concrete’ – a nice, easy way to remember the importance of the base make up.

Concrete Plinth Specification

1. Excavation

It can become awfy costly if your planned site has terrible access and is on, what some may describe as, a cliff face.

The Excavation is where the groundsmen dig down to firm ground and level off the site in preparation for the next stage. Every site is different and that is why a ‘ballpark’ figure isn’t always achievable until a site visit is carried out.

2. Hardcore

The bottom of the base needs a solid foundation to withstand the weight and form of the concrete and the building. The Hardcore is levelled out and compacted with a whacker to provide a stable sub-base.

3. DPC

This is the damp proof course which is needed to stop any damp seeping through the concrete floor. It’s really important not to miss this stage because if you have additional moisture in your concrete it can freeze and crack the entire base.

4. Form

Using timber supports, the groundsman will create a form to pour the concrete into. This makes a mould for the concrete to set in.

5. Pour and Finish

Pouring the concrete is usually done by the concrete supplier, to make sure of an even distribution across the full area. The Groundsman can then screed the concrete before finishing by floating it to a smooth need finish.

This isn’t something we would recommend trying yourself, as the plinth needs to be level and in-square – something that isn’t easy to do ‘off-hand’.

At Gillies and Mackay we recommend Carmichael & Baxter for all our concrete bases. We love C & B because they know what we’re talking about. They are kind and thoughtful when dealing with our customers and they get the job done when they say they will, and with the utmost precision.

Ground Screws

Ground screws are an eco-friendly alternative to concrete and offer more flexibility.

The screws are bored into the ground creating a solid, level framework to build the structure’s base on. It is a quick and tidy procedure and much less damaging to the environment than a concrete based foundation.

No More Digging in Dundee has been a great addition to our recommended trade. We are headache-free when it comes to bad access sites or impossible excavation. We love working with them.

Callum at NMD has been able to help our customers get their dream Garden Room without disrupting/upsetting their original landscape or costing an absolute fortune because of labour.

The ground screws are fitted typically within 4 hours.

It’s important to note that ground screws are purely for the foundation of the building. So they will follow the lay of the land, which can mean the head of the screws will be visible. You may wish to add additional landscaping to hide these heads and help the building fit within its surroundings.

In a recent project with NMD, we asked for their help with a cliff facing site with restricted coastal access.

The results were perfect…

Preparation is everything and it’s entirely up to you which option you choose when it comes to your Garden Room and existing site.

We won’t leave you on your own with this though, part of the Garden Room ordering process involves us coming out to see your site and helping you decide what groundworks would work best.

We all need a good foundation in life and it’s no different for your Garden Room too.

All my #ShedLove

Natty x

Related Content:

• Garden Rooms: Do I need Planning Permission and/or Building Control
• What is the Best Construction for a Garden Room?
• DIY Garden Room: The Half Build