There is something deeply satisfying about building a garden bench from reclaimed timber. It is a weekend project that costs very little, keeps good wood out of the skip, and gives you a sturdy seat that looks completely at home in a rustic garden. The method below is straightforward: cut treated boards to size, sand sharp edges, and assemble with galvanised screws. You do not need a workshop full of fancy tools—just a bit of patience and a willingness to measure twice and cut once.

Why reclaimed timber makes a fine bench

Reclaimed timber is often denser and better seasoned than new softwood, because it has already been through years of changing seasons. Old scaffold boards, floorboards, and fence panels are ideal candidates. They come with dents, nail holes, and a patina that new timber simply cannot match. As long as the wood is not rotten or riddled with woodworm, it will make a solid bench.

• Scaffold boards are typically 225mm wide and 38mm thick—perfect for seat slats and legs.
• Old floorboards are usually thinner but can be doubled up for strength.

Check every board for embedded metal. A quick pass with a metal detector or a strong magnet saves saw blades and drill bits. If the timber was previously treated, it may only need a fresh coat of preservative. If it is bare, treat it after cutting.

Gather your tools and materials

For a bench roughly 1.2 metres long, 40 centimetres deep, and 45 centimetres high, you will need the following. Adjust the lengths to suit your reclaimed boards.

• Tools: tape measure, carpenter’s square, pencil, hand saw or circular saw, drill/driver, random orbital sander, clamps, safety glasses, ear defenders, and a dust mask.
• Materials: reclaimed treated boards (enough for four legs, two long rails, two short rails, and five seat slats), 80mm and 50mm galvanised screws, exterior wood glue, wood preservative or exterior oil, and sandpaper in 80, 120, and 180 grits.

Galvanised screws are non-negotiable for UK weather. They resist rust far better than plain steel, and they will not leave black streaks on the timber. Buy more than you think you need—reclaimed wood can be unpredictable.

Cutting and sanding your boards

Start by planning your cuts on paper. A simple backless bench has two side frames (each made from two legs and one short rail) and two long rails that connect them. The seat slats sit on top. Here is a typical cutting list for a 1.2m bench:

• 4 legs: 45cm long
• 2 short rails: 35cm long
• 2 long rails: 1.2m long
• 5 seat slats: 1.2m long, ripped to about 70mm wide if needed

Cut all pieces to length, then sand every cut end and edge. This step is often rushed, but it makes the difference between a rough seat and a comfortable one. Start with 80 grit, move to 120, and finish with 180. Round over the front edge of the seat slats so it does not dig into your legs.

Assembling the bench frame

Build the two side frames first. Clamp one leg to a short rail, check that the angle is square, and drill pilot holes. Drive two 80mm galvanised screws through the rail into the leg. Repeat for the other leg, then do the same for the second side frame. A smear of exterior wood glue on each joint adds strength and helps seal out moisture.

Next, connect the two side frames with the long rails. Position one long rail at seat height (about 40cm from the ground) and clamp it in place. Check that the whole assembly is square by measuring the diagonals—they should be equal. Drill pilot holes and drive 80mm screws through the side frames into the ends of the long rails. If you want a lower stretcher for extra rigidity, add a second pair of long rails near the bottom.

Attaching the seat slats

Lay the five seat slats across the long rails. Space them evenly with a gap of 5–10mm between each one. These gaps let rainwater drain away and stop the seat from becoming a puddle. Use a small offcut or a drill bit as a spacer to keep the gaps consistent.

• Pre-drill each screw hole to prevent splitting, especially near the ends of the slats.
• Use 50mm galvanised screws, two per slat at each end.
• Countersink the screw heads slightly so they sit just below the surface.

Once all slats are fixed, give the whole bench a final sand with 180 grit. Run your hand over the seat—if you feel any roughness or raised screw heads, deal with them now. A quick wipe with a damp cloth removes dust before finishing.

Protecting and maintaining your bench

Apply a generous coat of wood preservative or exterior oil to every surface, including the underside and the end grain. End grain soaks up finish like a sponge, so give it an extra pass. Two coats are better than one, allowing the first to dry before adding the second. This not only protects the timber but also brings out the natural grain and colour of the reclaimed wood.

Your bench will weather gracefully if you look after it. Once a year, check all the screws and tighten any that have worked loose. Sand down any rough patches and apply a fresh coat of oil or preservative. If a slat ever splits or rots, you can simply unscrew it and replace it with another piece of reclaimed timber. That is the beauty of this design—it is easy to repair and easy to adapt.

With a little care, your reclaimed timber bench will give you years of dependable service.