Quail Bunker — Master Blueprint

You have 18 lengths of 2400mm (38×63mm) timber. Sort them into the groups below. Note: floor joists and side plates are cut to different lengths — read Group 2 carefully before cutting. Stud offcuts come from the waste of the cross-cut pieces.

1. Mud barrier: Lay your paving slabs over an area slightly larger than 2400×1220mm. Level them carefully — the floor frame will sit directly on top. Place stacked concrete blocks at each corner and at mid-span as your raised legs.
2. Floor frame (joists at 600mm centres): Lay your two uncut 2400mm rim joists parallel, 1144mm apart. Place one 1144mm joist flush at each end. Then position the three remaining joists at exactly 600mm, 1200mm, and 1800mm from the left-hand rim. Align each joist face flush with the top of the rim. Drive two 80mm screws through the rim into each joist end — don't nail, screw.
3. OSB deck: Drop the uncut 18mm OSB sheet onto the frame. The sheet is 2440mm wide; your frame is 2400mm — let it overhang by exactly 20mm on each side. No overhang front-to-back (both are 1220mm). Screw down every 300mm along every joist with 50mm screws.

1. Front wall frame (600mm tall): Lay two uncut 2400mm lengths flat as your top and bottom plates. Using your four 524mm studs: place one flush at the left end, one flush at the right end. Measure 1400mm from the left and fix your third stud — this is the door-side jamb. Place the fourth stud midway through the remaining 1000mm gap (at ~1700mm from left) to give the mesh panel mid-support. Fasten each stud with two 80mm screws top and bottom.
2. Back wall frame (500mm tall): Same process with two 2400mm plates and your five 424mm studs. Place one at each end, then space the remaining three at exactly 600mm, 1200mm, and 1800mm — matching the floor joist positions. This transfers vertical load cleanly.
3. Stand and fix: Lift the front wall frame onto the front edge of the floor deck and screw down through the bottom plate with 80mm screws at 400mm centres. Repeat for the back wall. Join front and back frames at top and bottom using your four 1094mm side plates — two per side, one at floor level and one at the top. These plates span the gap between the two wall frames once they are standing on their 63mm faces; 1094mm is the correct length for this (not 1144mm).

1. Human door — size the blank: Measure the actual inside dimensions of the 1400mm opening once the wall is standing (it may vary slightly). Cut your door blank 10mm narrower and 10mm shorter than the measured opening — giving a 5mm clearance gap all round to allow for wood movement in wet weather.
2. Z-brace the door: Fix two horizontal rails across the door — one near top, one near bottom — using 80mm screws. Cut a diagonal brace from a timber offcut and fix it between the rails. Critical: the bottom of the diagonal must point toward the hinge side. This is what stops the door sagging. A diagonal pointing the wrong way actively causes the door to drop.
3. Hang and latch: Fix two heavy-duty gate hinges to the left stud of the door opening, then screw them to the door. Fit a padbolt on the right-hand closing edge.
4. Pop-hole: In the bottom-right corner of the static mesh panel area, frame a 250×250mm opening using timber offcuts. Cut an OSB blank to match, fitting it with two small hinges at the top (so it swings upward and rests against the wall when open — gravity keeps it shut without a latch in normal use). Add a turn-button at the bottom to lock it at night.

1. Back wall cladding: Take the 2440×500mm OSB strip and screw it horizontally to the outside face of the back wall frame. The sheet is 2440mm, the frame is 2400mm — it will overhang 20mm each side, matching the floor deck. Use 50mm screws at 300mm spacing.
2. Side panels: Fix each slanted OSB side panel to the outside of the side frames. The tall edge (600mm) aligns with the front, the short edge (500mm) with the back. This creates your natural roof slope — approximately 1:12 pitch, enough to shed water reliably.
3. Roof purlins: Lay the three remaining uncut 2400mm timbers horizontally across the top of the frame — one at the front, one at the back, one centred at 600mm from the front. Screw each purlin down into the top plates of the side walls with two 80mm screws per end.
4. OSB roof deck: Lift the uncut 2440×1220mm 11mm OSB sheet onto the purlins. Overhang 20mm on each long side, same as the floor. Screw down into all three purlins at 300mm centres.
5. Bitumen roofing sheets: Lay the three corrugated sheets on top of the OSB, working from the lower (back) edge to the upper (front) edge. Overlap each sheet mid-span as required. Fix with corrugated roofing screws through the crown of each ridge only — never through the valley. Drilling through valleys lets water pool around the screw and leak directly in.

1. Mesh all open faces: Cut and staple your ½" galvanised welded mesh across the door frame and the static front panel. Use staples every 50–75mm along all timber edges — no gap between staples greater than 75mm. Pull the mesh taut before fixing; loose mesh sags over time and creates gaps at the edges. Fold all cut edges back on themselves by 10mm before stapling so there are no exposed sharp wire ends on the interior face.
2. Rat skirt: Cut strips of mesh offcut and staple them around the full perimeter of the raised floor, letting the wire drape down to rest on the paving slabs. Fold the bottom edge outward by 100–150mm (laying it flat on the slabs). Weight it down with spare blocks or bricks. This prevents rats from tunnelling straight up under the floor edge.
3. Interior finishing: Pour play sand into a shallow tray or lipped area — quail need a dust-bathing area to stay healthy. Add wood shavings across the floor for bedding. Wrap any exposed metal screw points or bracket edges with foam pipe insulation secured with zip ties.

Untreated CLS timber is not designed for permanent outdoor exposure. Without treatment it will absorb moisture, swell, and begin to degrade within one to two seasons. Treating the structure properly before birds move in adds years to the build and reduces maintenance significantly.

When to treat

Treat all external timber surfaces before assembly where possible — it is far easier to coat individual pieces than to work around mesh, fixings, and corners once built. Apply a second coat to all exterior faces once the structure is fully assembled, paying particular attention to end grain (cut ends), which absorbs moisture fastest.

Recommended products

1. Exterior wood preservative (base coat): Apply a water-based or solvent-based wood preservative to all structural timber before assembly. Products such as Barrettine Wood Preserver, Cuprinol Wood Preserver, or Ronseal Total Wood Preserver are widely available. These penetrate the grain and protect against rot and fungal decay. Two coats minimum — allow the first to dry fully before applying the second.
2. Exterior wood paint or stain (finish coat): Once the preservative is dry, apply an exterior wood paint or opaque stain to all exterior-facing surfaces. A darker colour (forest green, dark brown) will absorb heat slightly and extend the life of the coating. Lighter colours reflect UV and stay cleaner in dirty outdoor environments. Either works — choose based on preference. One coat is functional; two coats is recommended.
3. Roofing sheet edges: Apply bitumen mastic sealant to the front edge of the uppermost roof sheet and along both side edges where the sheets meet the OSB. This prevents wind-driven rain from getting under the overlap.

Ongoing maintenance

Inspect the structure at the start of each season. Re-treat any areas where the coating has cracked, flaked, or worn through — particularly on south-facing surfaces and any area that stays damp. Re-apply a full exterior coat every 2–3 years depending on exposure. The corrugated bitumen roof sheets are maintenance-free but check the screw fixings annually and re-seal any that show rust or movement.

Run through this before moving birds in. Each point has caused losses in similar builds when missed.