Foundation

WHAT IS THE BEST FOUNDATION FOR YOUR CABIN?

Wondering what the best foundation is for your shed or cabin? We can help with a few options on how you could best prepare the ground surface ready for the build.

Most importantly the ground needs to be level. Why? An uneven surface or moving ground could cause the doors to jam and not open/shut with ease. It could cause part of the shed to drop or boards to become loose.

The most popular option for the smaller cabin foundations (3mx3m size) is 6 x H4 treated ground bearers, most choose to purchase these from their local hardware store and use them on level ground. However you may ask yourself, what is the best surface or foundation for my shed?

You have several options, and these depend on;

How flat the surface is that you wish to place your shed on. Whether you may wish to move your shed in the future. Do you want to add a small deck? How much weight do you want to place on the floor of your shed?

Ground

The easiest and quickest option for those with a very flat surface is to place your treated bearers straight on the ground. This can be on grass if you have a nice hard, flat site, this makes it relatively easy to move it later. You could place the bearers on large concrete pavers to assist in spreading the load onto the ground. Please note, this is only possible when placing the cabin on very stable & hard ground.

This is also very similar to placing your shed on skids

Skids – Great for small sheds or cabins
  

If you are wanting to move your shed around your property, make sure your skids are strong and can take the weight and movement of the shed. Generally, the larger the shed, the larger and stronger the skids need to be. Notching into your floor joists or bearers will help with strength.

Another option that is relatively simple and cost effective is to make a gravel pad to place your shed bearers on.

To do this you must measure the size of the surface area you will be needing (larger than your shed size is always a good option).

Gravel Pad – Great for smaller sheds or cabins

Step 1. Dig out the soil to a depth of approx. 15 cm and check your surface is level.

Step 2. Create a frame around your square with some 6” x 1” timber (this will help to stop the dirt falling back in and create a solid surface).

Step 3. Lay a membrane over the exposed earth to help stop moisture. (this is optional).

Step 4. Add your gravel keeping it slightly lower than the top of your timber.

Your treated bearers will then have a good solid base to sit on.

You could opt to place your bearers on a concrete pad. This is a more expensive option but will create a good solid base.

Concrete Pad – Great for Small or Large Cabins

Step 1 Mark and measure the area.

Step 2 Create the frame with timber

Step 3 Dig out the area, removing roots of trees. Level and compact the soil.

Step 4 It’s a good idea to use reinforcing mesh in your slab, even if it is only a small garden shed, as this prevents the concrete from fracturing over time. Pour your concrete filling the whole area.

Step 5 Screed off, making the concrete level. Tamp down well in the corners. As the concrete begins to set, smooth off with a trowel to achieve the desired finish.

Step 6 Let the concrete cure. (If the weather is hot and dry, water down the concrete with a hose to stop it drying out too fast.) Give it at least a week to cure correctly (you can cover it with plastic or a tarpaulin to help slow the drying process).

Notes: When placing your cabin on a concrete slab, make sure the slab is exactly the same size as the cabin foot print, this is to prevent rainwater from falling on the slab & travelling in under your building. It’s a good idea to make sure the finished floor level of your slab is raised above the natural ground level to help prevent runoff water from traveling in under your cabin. If you wish to place a concrete path, veranda or porch along any side of your shed or cabin, ensure that the finished level of the path or veranda is more than 75mm below the level of your cabin slab, this will also assist to minimize run of water from traveling in under your shed or cabin.

Blocks/Piles – Great for uneven ground levels

Another option that works well for a flat or contoured site, is to sit your wooden shed on blocks or piles. These can be either floating (sitting on top of the ground for a flat site) or you could choose to concrete them in place if your site is not level (a more permanent option). This lifts your shed up off the ground and gives you the opportunity to create a level base with the bonus of being able to add a small deck or steps.

Make sure you have enough blocks/piles for the size of your shed as you want to make sure your timber bearers are not put under excessive strain.

If you choose to put in piles this will also provide a good solid anchorage point for those sheds that are in high wind zones.

STEEEL FRAME – Great for Small or Large Cabins or wanting to move it in the future.

A steel frame is a good option if you wish to move the shed to a different location in the future. Transportation is easier with the steel frame attached to the shed.

 

GROUND SCREWS

Ground screws are also a great alternative for installing your cabin or shed on, in conjunction with a bearers & joist system (timber or steel). Ground screws have a lot of great bonuses, no soil removal required, no concreting required. Fast & simple construction method, ideal for cabins “Great or Small”. Ground screws can be purchased & installed by the DIY’er or purchased & installed by professionals such as Krinner Australia/New Zealand, ground screws are also available from hardware stores such as Bunnings. With the ground screw system there’s no need to wait for the concrete to set you can start your construction right away! Helping those that are tight for time to achieve more in less time. One great advantage is the ground screws can even be removed if you wish to move your cabin in the future…..with no concrete to dispose of.

Whatever you think may work well for you and your site, remember it is always a good idea to put a little bit of research into what works best for your area. Always make sure your shed foundations are level and take into consideration the size of your shed, your site, what purpose you have for your kitset shed and weigh this up with the cost to make your project a positive experience.

This is written to the best knowledge and research of the writer. Fort Group, SheShedz and Homelandz take no responsibility for misguided, misused information. This is correct at the date written and it is instructed that all purchasers of sheds do their own investigation to what consents apply in their local council.

Check out some photos here of different foundations customers have used:

A spa shed on a concrete base to hold the weight of the spa

Kitset Shed on piles

                                        Lofty Foundations – Before & After                   

   
Raised Deck