What's inside
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A porch package box keeps deliveries out of rain and away from the street, but it is not a secure substitute for a locked parcel locker. This beginner-friendly plan uses a simple plywood body, a hinged lid and a hasp for a small padlock. Build it to suit the packages you actually receive, and give water a way to drain rather than relying on a perfect seal.
Contents
Choose a size and a spot
A useful starting size is about 24 inches wide, 18 inches deep and 24 inches high, measured on the outside. That holds many small and medium parcels without taking over a narrow porch. Before buying material, measure a typical delivery and allow at least 2 inches of clearance on each side. Check that the lid can open fully without hitting a wall, railing or door.
Place the box on a level surface under an overhang if possible. Keep it clear of the door swing and leave a visible delivery label or instruction where the driver can find it. If the box will sit in direct weather, use exterior-rated materials and plan for regular inspection. A covered porch is still exposed to wind-driven rain and damp air.
Pick materials for your weather
For a first build, exterior-grade plywood is easier to square and assemble than a frame made from many narrow boards. Use 1/2-inch plywood for the sides and back, and 3/4-inch plywood for the bottom and lid. Exterior-rated plywood resists moisture better than interior plywood, but it is not waterproof; protect every face and especially the cut edges.
| Material | Good fit | Trade-off |
|---|---|---|
| Exterior plywood | Fast, straightforward box construction | Edges need sealing; veneer can delaminate if water gets in |
| Cedar boards | Lighter box with naturally rot-resistant wood | Costs more, and boards can move or open small gaps |
| Pressure-treated lumber | Parts that sit close to damp concrete | Often wet and prone to movement; let it dry before finishing |
For most beginners, exterior plywood is the sensible choice. Cedar is a reasonable upgrade if you want a wood-board look and accept more fitting work. Pressure-treated lumber is usually unnecessary for the whole box; keep the box raised instead. Buy exterior-grade plywood from a local lumberyard or home center, and confirm the panel is rated for exterior use rather than assuming any plywood will do.
Gather tools and hardware
You will need a tape measure, square, pencil, circular saw or panel saw, drill-driver, and clamps. A handsaw can trim small parts, but making straight, repeatable cuts in a full sheet is harder without a circular saw and a straightedge guide. Wear eye and hearing protection, and support the sheet so the offcut cannot pinch the blade.
Use exterior screws around 1 1/4 inches long for the 1/2-inch sides, and about 1 5/8 inches for the thicker bottom and lid cleats. Predrill near plywood edges to reduce splitting. A pair of 24-inch continuous hinges spreads the lid load well; two sturdy butt hinges are cheaper and adequate if mounted carefully. Compare stainless continuous hinges with standard exterior-rated hinges based on cost and the weight of your lid. Add a hasp and a small padlock only if you need a deterrent; a thin plywood box can still be forced open.
Cut the panels
For an outside size near 24 by 18 by 24 inches, cut the following from 1/2-inch exterior plywood: front and back, each 24 by 24 inches; and two sides, each 17 by 24 inches. The sides fit between the front and back, producing an outside depth of 18 inches. Cut a 3/4-inch bottom panel to 24 by 18 inches, then fit it inside the walls or fasten it underneath. A lid around 25 by 19 inches gives roughly a 1/2-inch overhang on each edge.
These dimensions are a starting point, not a reason to waste a sheet. Lay out the cuts before sawing and adjust to the plywood panel you can buy. Mark each piece, check the measurements twice, and keep the factory edges where they help alignment. If the box must fit a specific porch space, prioritize the outside dimensions and resize the panels accordingly.
Assemble the box
Set the front and back upright, sandwich the side panels between them, and clamp the corners square. Drill pilot holes and drive screws about every 6 inches, keeping them at least 3/8 inch from the panel edges. Measure both diagonals across the open top; if they differ, nudge the box until they match before tightening the screws. A small mismatch can make the lid bind later.
Fit the bottom flush with the lower edges and fasten it to all four walls. Drill four to six 1/4-inch drainage holes through the bottom, spaced away from the corners. Add two narrow runners underneath so the bottom does not sit directly on wet concrete. Do not block the holes with runners or place the box where water naturally pools.
Fit the lid and finish it
Center the lid on the box with an even overhang. Fasten the hinges to the back edge, checking that the lid opens freely and does not scrape the wall. Add a lid support or chain if the lid is heavy; a lid that falls shut can pinch fingers. Install the hasp at the front only after confirming the lid sits flat.
Round sharp edges lightly with sandpaper, then seal the plywood faces, cut edges and screw holes with an exterior paint or a finish labeled for outdoor use. Follow the product’s drying instructions and coat the underside as well as the visible surfaces. Paint helps protect the wood, but exposed edges and standing water remain common failure points. Recheck the finish each year, tighten loose hardware and clear the drainage holes.
Use it with realistic expectations
Leave the lid easy for a driver to lift, and provide delivery instructions through the carrier’s available options. Do not assume a box placed on the porch will be used unless the driver sees it and knows what it is for. In heavy rain, water may still enter around the lid; a small overhang and a sheltered location help more than trying to make a beginner-built lid perfectly watertight.
Inspect the bottom and lower corners after the first wet season. Soft plywood, swollen edges, loose hinges or a lid that no longer closes square are signs that water protection needs attention. Replace damaged parts early. A modest box built from ordinary exterior plywood can serve well on a covered porch, but an exposed site or valuable deliveries may call for a purpose-made, lockable parcel box instead.