Choosing the right base is the first step to a shed that stays square, dry, and durable. A good foundation keeps the structure level, reduces movement, and helps prevent damp from creeping into the floor. Even a well-built shed will struggle without a sound base, so it pays to plan this part carefully before you order materials or book time for the build.
At BTL Timber, we stock the quality materials you need to create reliable shed bases and timber buildings. We supply a wide range of quality timber sheds, so we have created this guide to explain the common base options and how to choose the right one for your garden, your shed size, and your budget.
Considerations For Your Timber Shed Foundation
A shed base isn’t one-size-fits-all. The right choice depends on ground conditions, shed weight, and how you’ll use the space. Think about the points below before you start digging or laying anything permanent.
Stability & Size: Make the base slightly larger than the shed footprint and perfectly level to stop racking and door misalignment.
Drainage: Encourage runoff and avoid low spots; standing water shortens the life of timber floors.
DIY vs Professional Installations: Gravel and paving suit capable DIYers; concrete usually benefits from professional casting.
Longevity: Concrete lasts longest; timber and gravel are easier to adjust or move later.
Budget: Timber and gravel are cost-effective; paving sits mid-range; concrete costs more but offers maximum stability.
When you know your priorities, match them to the foundation type. Light, moveable sheds often suit a timber or gravel base. Heavier workshops or storage buildings benefit from paving or concrete, which spread weight and keep everything steady through the seasons.
Our experienced timber merchants at BTL Timber can help you source the right materials: treated structural timber, sleepers, joists, sub-base aggregates, and sheet goods for floors and packers. Contact us now for more information.
Timber Base
A timber base uses pressure-treated bearers or a framed platform to lift the shed off the ground. That raised design improves airflow, helps the floor dry out after wet weather, and reduces the risk of damp. It’s quick to assemble, friendly to uneven gardens, and ideal when you may want to move or replace the shed in future.
Use quality, pressure-treated timbers from BTL Timber, set on level pads or adjustable supports with a geotextile membrane beneath to suppress weeds. Keep consistent spacing between joists, fix securely with exterior screws, and check levels as you go. Re-treat cut ends and maintain clear airflow all round. A timber base is cost-effective, fast, and forgiving - perfect for light to medium-weight sheds.
Concrete Slabs
A poured concrete slab is the gold standard for long-term stability. It creates a single, rigid surface that resists movement, carries heavy loads, and stays true for decades when done right. If you’re planning a large workshop, heavy equipment, or regular footfall, a slab keeps doors aligned and floors flat.
Concrete requires careful prep; excavate, compact a sub-base, add a damp-proof membrane, set formwork, and pour to an accurate level. Many customers bring in professionals at this stage. BTL Timber supplies shuttering timber and packers; we don’t install. Once cured, the slab needs little maintenance. It costs more upfront but pays back in service life and stability for big, heavy sheds.
Gravel Base
A compacted gravel base is a brilliant DIY option with excellent drainage. Excavate to depth, lay a weed membrane, add and compact layers of sub-base, and strike off level. You can then sit a timber bearer frame on top or use heavy-duty blocks to support joists at intervals.
The big win with gravel is water control - rain drains through rather than pooling under your shed. It’s easy to correct minor settlements by raking and re-compacting, and it’s kinder to budgets. Pair the sub-base with treated bearers from BTL Timber and you’ll have a stable, breathable platform that suits small to medium sheds without the permanence of concrete.
Paving Slabs
Paving slabs offer a tidy, durable base that sits between gravel and concrete in terms of permanence and price. Lay them on a well-compacted sub-base with a sharp-sand or mortar bed, checking levels with a straightedge and spirit level. Aim for full support under each slab - not just the corners - to avoid rocking or point loading.
A properly laid paving base resists weeds, drains well, and gives you a clean, level surface that looks smart around the shed perimeter. It’s a strong choice for mid-sized sheds and hobby spaces. BTL Timber can supply the timber bearers and floor materials that sit over your paved base.
Contact BTL Timber For Quality Timber Sheds
Ready to build it right first time? BTL Timber supplies the pressure-treated timbers, joists, sleepers, sheet materials, and accessories you need for a solid shed base and a long-lasting timber building. We supply only but our friendly team can help you choose the right materials for your site, shed size, and budget as well as recommend local tradesmen to help. Visit us in Bishop Auckland or browse online; with BTL Timber, you get dependable products, practical guidance, and the confidence to build a base that lasts.
