Build a Covered Structure

Choose the type: open pergola (slats, climbing plants, light shade), semi-open covered structure (closed roof, open sides) or enclosed veranda (one or more walls, possibly glazed). Decide on location: freestanding in the garden or attached to the house (wall-mounted).

Permits: often permit-free up to 50% of the rear plot and max. 3 m height, with setback rules to the boundary. Exceptions apply for building regulations, aesthetics and listed buildings. Always check the Omgevingsloket before you cut timber — and have the drawing ready for your application.

Dimensions: comfortable seating needs at least 2.30–2.50 m clear height. Width and depth in steps of 60 cm or 1.20 m keeps material use efficient. Draw posts, beams and roof direction to scale, including gutter and fall.

Timber choice: Douglas fir (strong, warm, needs treatment) or hardwood (more expensive, longer low-maintenance). Posts often 12 × 12 cm or 15 × 15 cm Douglas fir; for larger spans dimension heavier. We help with a custom timber list — send a sketch and photo.

Set out the four (or more) corners with pegs and builder's line. Measure both diagonals: equal = square. Mark each post position.

For wall mounting: check whether the wall is strong enough for a wall plate or anchors, and whether the house rainwater discharge is in the way. Plan the structure gutter so it does not discharge into the house downpipe without coordination.

Cables: KLIC notification when digging. Run empty conduits now for lighting and a socket — drilling through a post afterwards is a waste.

Ground: remove turf at pier positions. If you plan a deck under the structure later: align levels now so you do not have to shorten joists later.

Mount posts plumb (spirit level on two sides) and brace temporarily. Check the diagonals of the ground plan again.

Main beams: connect posts with heavy beams (often 6.3 × 17.5 cm or heavier, depending on span). Use stainless or galvanised timber connectors, joist hangers or half-lap joints — not "screws in the end grain only" for load-bearing connections.

Purlins/rafters: centre-to-centre usually 50–60 cm for EPDM or roof decking; for polycarbonate follow the panel grid from the manufacturer. Build in fall: flat roof minimum 1.5–2% towards the gutter.

Connections: pre-drill, stainless bolts or screws of sufficient length. With Douglas fir: account for checking along the grain — do not tension until the timber splits.

Wall mounting: fix the wall plate with approved anchors into the wall structure, not just into plaster. Unsure about the wall? Have a structural engineer or us advise.

Treat Douglas fir within a few weeks of installation (stain or oil, including end grain). Hardwood: oil or let it grey. Protect all cut faces again.

Check: sit test in wind — if a post moves visibly, a brace or heavier foot is needed. Check anchors for rust annually, retighten bolts, and clear the gutter of leaves.

Common mistakes: posts too light for the span, no real foundation (tiles only), flat roof without fall, and cheap non-stainless connections that sag.

Need help? Send a sketch with dimensions, whether freestanding or attached to the house, and a photo of the site. We'll prepare a timber package and quote — and can advise on the structure if needed.