Tier 2 · ExpansionScale up with your beesAdditional brood space for thriving, established colonies. The modular way to give your bees more room as the season progresses — without transferring to a new box or disrupting the colony. Made from the same ultralight, waterproof EPP material as the core nuc. Modular Expansion SystemAdd brood space as you need itThe Brood Box Extension gives you an additional 6-frame brood chamber that stacks seamlessly with your existing poly nuc. Perfect for mid-season expansion when your colony is building fast and needs more laying space.Doubles Your Brood CapacityStack the extension on top of your existing brood box to create a double-brood nuc — giving the queen twice the laying space without changing boxes.Keep the Colony TogetherNo need to transfer frames to a new box or split the colony. Just stack the extension and let the queen expand naturally into the new space.Mid-Season UpsellIdeal timing is late spring through summer when colonies are at peak expansion. Add the brood box extension proactively before congestion becomes swarming pressure.Works with or without the EkeStack it on a standard nuc or on a 14×12 configuration — the brood box extension fits either way, giving you complete flexibility. Brood Box Extension Modular Stacking Preventing CongestionWhen your colony outgrows the nucAs colonies build up through late spring and summer, brood congestion becomes a risk. Adding a second brood box gives your bees the space they need before swarming pressure forces your hand.Control Swarming PressureA congested brood nest is one of the main triggers for swarming. More laying space means less pressure — and less likelihood of your colony splitting before you’re ready.Maximise Honey ProductionA large, thriving brood nest means more foragers. More foragers means more nectar. Double brood gives you the colony strength needed for a serious honey crop.Removable and ReusableIf you need to downsize for winter or split the colony later, simply remove the extension. Fully modular — use it when you need it, store it when you don’t. Same EPP MaterialAll the benefits of EPPThe brood box extension is manufactured from the same Expanded Polypropylene as the core nuc — meaning it’s ultralight, waterproof, impact-resistant, and never needs painting.No Painting RequiredEPP’s UV-stable neutral colour is permanent. Simply wipe clean each season — no brushes, no prep, no maintenance.Superior InsulationEPP’s thermal properties keep colonies warmer in winter and cooler in summer — maintaining optimal brood conditions year-round.UltralightEPP is one of the lightest hive materials available — even a fully loaded double-brood nuc remains easy to lift and transport. Technical SpecificationsFull product specificationsProduct TypeBrood Box ExtensionCompatibility6 Frame Dual Poly Nuc (stacks on top of existing brood box)Frame StandardBritish NationalFrame Capacity6 frames (or 2 × 3 frames when split)MaterialExpanded Polypropylene (EPP) — NOT Expanded Polystyrene (EPS)InstallationStacks on top of existing brood boxFloor TypeBrood box only — no integrated floor (stacks on existing nuc base)Divider CompatibilityWorks with standard Correx divider or aluminium composite divider (sold separately)UV FilterBuilt in — colour is permanent, no painting requiredPainting RequiredNo — but you can paint with standard smooth masonry paint if preferredWaterproofYes — EPP has zero water absorptionRecyclableYes — 100% EPP, fully reprocessableAvailabilityExclusively from Old Castle Farm Hives Expand Your SetupThe complete Poly Nuc rangeEvery product in the range is designed to work seamlessly with your 6 Frame Dual Poly Nuc. Build the exact setup your apiary needs — from a second complete box to individual replacement parts. Tier 1Core Products — Complete, Ready-to-Use Standard · £54.996 Frame Dual Poly Nuc — StandardThe hero product. Full 6-frame British National nuc with 3.5L feeder, Correx divider, mesh floor, lid, and 2× entrance discs. Complete kit — nothing extra to buy. View product → 14×12 Version6 Frame Dual Poly Nuc — 14×12The standard nuc with the 14×12 eke extension pre-installed — full 14×12 brood depth straight out of the box. Ideal for beekeepers who run exclusively 14×12. View product → Tier 2Expansion — Scale Up the Colony Expansion14×12 Eke ExtensionConverts your standard poly nuc to full 14×12 brood depth — giving a growing colony more space without buying a new box. Fits between brood box and feeder. View product → ExpansionBrood Box ExtensionAdditional brood space for thriving, established colonies. The modular way to scale up with your bees as the season progresses — expand, don’t replace. View product → Tier 3Transport & Management TransportVented Transport LidPurpose-designed ventilated lid that fits the 6 Frame Dual Poly Nuc precisely. Keeps bees safe, calm, and ventilated during transport. View product → TransportMesh Transport BagCordstring mesh bag for safe transport of the poly nuc. Additional security and ventilation when moving colonies — particularly useful at shows and collection points. View product → Tier 4Upgrades — Premium Component Alternatives UpgradeAluminium Composite DividerUpgrade from the standard Correx divider to a precision-cut aluminium composite version — maximum durability and years of repeated use. Fits without modification. View product → UpgradeStainless Steel Entrance Discs (125mm)Premium corrosion-proof stainless steel alternative to the standard plastic entrance discs. 125mm — purpose-sized for the OCF entrance housing. A one-time buy that outlasts the hive. View product → Tier 5 — Spare PartsKeep every nuc in serviceNothing ever needs replacing wholesale. Individual spare parts mean a single worn or damaged component is a quick, cheap fix — not an excuse to buy a whole new box.PartDescriptionLinkReplacement Feeder (3.5L)Top feeder — liquid syrup or fondant/pattie.View →Replacement LidStandard lid with hive strap recess.View →Replacement Correx Divider (Standard)Standard-depth Correx dividing board. Colour may vary.View →Replacement Correx Divider (14×12)14×12 depth Correx divider for use with the eke extension.View →Spare Perspex Feeder Panels (×2)Replacement Perspex panels for the 3.5L top feeder.View →Spare Silicone Bung (Feeder)Replacement silicone bung for the feeder hole. Apply petroleum jelly and twist firmly for a leak-free seal.View →Plastic Entrance Discs (125mm)Standard plastic hive entrance discs — 125mm.View →Stainless Steel Entrance Discs (125mm)Premium corrosion-proof stainless alternative — 125mm.View → Scale up with your bees — expand, don’t replaceModular brood expansion. Doubles your brood capacity. EPP construction. No painting required. Exclusively designed and available only from Old Castle Farm Hives. Add to Basket
