This is a Construction Manual for a Solitary Bee House a recipe book for everyone

2construction manual for a solitary bee house INDEX CHAPTER no. 1 INTRODUCTION CHAPTER no. 3 PHASE 1 / FIND YOUR MATERIALS CHAPTER no. 4 PHASE 2 / BUILD THE SKELETON CHAPTER no. 5 PHASE 3 / PREPARE YOUR MYCELIUM CHAPTER no. 6 PHASE 4 / FINAL ASSEMBLY CHAPTER no. 2 SELECTION OF THE ABANDONED LOT

3a recipe book for everyone

4construction manual for a solitary bee house introduction ABANDONED LOT The territory offers countless abandoned lots, fragments of landscape suspended between the natural and the urban, often perceived as useless or degraded. These former industrial areas or construction remnants lack maintenance and constitute the most reactive urban ecosystems. LACK OF BIODIVERSITY Despite their reactivity, biodiversity in these lots is fragmented and requires a catalyst to thrive. The poor soils, typical of abandoned areas, are biologically perfect for being regenerated by targeted, low-impact interventions. The goal is to transform the void into habitat, creating the conditions to attract key species. CHAPTER no. 1 INTRODUCTION

5a recipe book for everyone chapter no. 1 URBAN REGENERATION Instead of large-scale projects, urban regeneration is introduced on a capillary scale. We use mycelium as a biodegradable matrix to reactivate the soils, taking advantage of the reduced human disturbance in these areas. HOME FOR SOLITARY BEES The completed device is a nest created for solitary bees, which are fundamental pollinators for the lot’s spontaneous vegetation. The independent colonization of the cavities by solitary bees completes the area’s regenerative cycle.

6construction manual for a solitary bee house introduction In a region where urban regeneration is often entrusted to large- scale interventions, this approach introduces a different dimension: that of small ecological infrastructures, dispersed within the city’s voids and capable of activating biodiversity from the ground up.

7a recipe book for everyone chapter no. 1 a solitary bee houses for renaturalize the abandoned lots

8construction manual for a solitary bee house introduction _Visualization of the device in the ground version, positioned in the abandoned lot.

9a recipe book for everyone chapter no. 1 _Visualization of the device in the raised version from the ground, positioned in the lot.

10construction manual for a solitary bee house selection of the abandoned lot In Lombardy, abandoned lots are a widespread and often invisible presence. Former industrial areas, small patches of residual land between the railway and the city, abandoned agricultural margins, and half-finished construction sites: these are suspended spaces, neither fully natural nor truly urban. Over time, these places become fragments of the landscape, isolated, perceived as useless or degraded. Abandoned lots are among the most reactive urban ecosystems: they host soils that, free from maintenance and constant human disturbance, begin to regenerate spontaneously through slow but active ecological processes. Lombardy, with its long industrial history, offers hundreds of sites in this condition. These lots possess three fundamental characteristics: A) reduced human disturbance, which allows devices to operate without interference; B) poor but biologically perfect soils for regeneration by mycelium; C) presence of spontaneous vegetation, which benefits from pollination by solitary bees. land uses: productive commercial offices residential degraded areas services agricoltural infrastructures CHAPTER no. 2 SELECTION OF THE ABANDONED LOT

11a recipe book for everyone chapter no. 2 _Census of brownfield sites in Lombardy 2022 (Interactive map, Politecnico di Milano)

12construction manual for a solitary bee house find your materials mold nesting tubes central tube Abandoned lots offer not only space but also unexpected resources. Among fragments of old structures, discarded pipes, wooden elements, pieces of rigid plastic, and small industrial leftovers, it is often possible to recover materials that are still functional. Carefully selecting these elements allows what remains of an urban past to become useful components for building the mycelium-based device. CHAPTER no. 3 PHASE 1 / FIND YOUR MATERIALS 1 2 3

13a recipe book for everyone chapter no. 3 connectors base raised base Collecting, evaluating, and reusing these materials means not only reducing waste but also establishing a direct dialogue with the site: each lot provides what is needed for its own regeneration. In this way, constructing the device becomes part of the place’s natural cycle, transforming residual resources into ecological micro- infrastructures. 4 5 6

14construction manual for a solitary bee house find your materials OBJECT no. 1 | Mold

15a recipe book for everyone chapter no. 3 DIMENSIONS: Inner diameter: 25-30 cm Height: 30-40 cm Thickness: 0.5-2 cm (suitable for maintaining shape during mycelium growth). SUITABLE MATERIALS: Industrial pressed cardboard tube Spiral cardboard jet tube such as Sonotube Recycled rigid PVC pipe (plumbing/ drainage) HDPE pipe (sewer/water) Galvanized sheet metal ventilation pipe Cylindrical steel container Rigid industrial plant pot (thick plastic) NOT SUITABLE MATERIALS: Drums with oil, solvent, glue/paint residues Fragile plastic (EPS, XPS, old PVC) Rusty or internally painted metal Copper or brass in direct contact with the mycelium Treated wood or phenolic plywood Rubber or materials that release odors/ chemical messes Containers from chemical or galvanic industries. Spiral cardboard jet tube type Sonotube HDPE pipe (sewer/water)

16construction manual for a solitary bee house find your materials OBJECT no. 2 | Central tube

17a recipe book for everyone chapter no. 3 DIMENSIONS: Inner diameter: 10-14 cm Length: 20-30 cm Thickness: 0.5-1.5 cm UITABLE MATERIALS: Galvanized sheet metal ventilation duct Industrial cardboard tube (used for carpets or fabrics) Very large bamboo cane segment Natural hollow trunk section Untreated cardboard tube NOT SUITABLE MATERIALS: PVC or other polymers (non-biodegra- dable) Heavy metals (they heat up excessively and do not degrade) Painted wood Oiled tubes Industrial cardboard tub Galvanized sheet metal ventilation pip

18construction manual for a solitary bee house find your materials OBJECT no. 3 | Nesting tubes

19a recipe book for everyone chapter no. 3 DIMENSIONS: Internal diameter: 6–9 mm Length: 12–15 cm Thickness: 2–8 mm SUITABLE MATERIALS: Bamboo canes Dried hollow branches Stems of tough weeds (e.g., Buddleja, Fallopia) Uncoated cardboard tubes NOT SUITABLE MATERIALS: Plastic (releases microplastics during degradation) Rusty metals that can become excessively hot Glass Coated or chemically glued tubes Treated or impregnated wood Bamboo canes

20construction manual for a solitary bee house find your materials OBJECT no. 4 | Connectors

21a recipe book for everyone chapter no. 3 DIMENSIONS: Diameter: 5-8 mm Height: 2-5 cm Thickness: 2-5 mm SUITABLE MATERIALS: Expansion bolts Metal or rubber tube connectors Natural ropes (hemp, sisal, jute) Thin coated wire Biodegradable twine NOT SUITABLE MATERIALS: Synthetic nylon or polypropylene ropes Strong chemical glues Plastic cable ties Rubber tube connectors

22construction manual for a solitary bee house find your materials OBJECT no. 5 | Base

23a recipe book for everyone chapter no. 3 DIMENSIONS: Inner diameter: 25-30 cm Thickness: 1-4 cm SUITABLE MATERIALS: Untreated raw wood (pallet boards, wood) Thick pressed cardboard disc (industrial drums) Thick recycled plastic sheets (HDPE or PP) (industrial crates or containers) Steel disc Pressed cork sheets NOT SUITABLE MATERIALS: Chemically treated wood (Tanalith, CCA) MDF and chipboard (contain formaldehyde) Rubber and elastic materials (may warp or absorb moisture unevenly) Thin, fragile plastic (EPS (polystyrene), old, very rigid PVC) Glass or mirrors Breathable cork coat Steel disc for brushing the screed

24construction manual for a solitary bee house find your materials OBJECT no. 6 | Raised base

25a recipe book for everyone chapter no. 3 DIMENSIONS: Diameter: 26-40 cm Height: 20-50 cm SUITABLE MATERIALS: Flat stones Reclaimed perforated bricks Untreated rough wood planks Old broken tiles (only if not glazed with lead) Metal pedestals NOT SUITABLE MATERIALS: Rubber (releases substances) Synthetic insulation materials Soft or impregnated parts Hollow building bricks Metal scraps on the construction site

26construction manual for a solitary bee house build the skeleton NECESSARY TOOLS : ELEMENTS: Pruning shears Drill Craft knife Micro saw (manual) Permanent marker Work gloves Small wire brush Skotch Mold Central tubes Nesting tubes Connectors Base Raised base CHAPTER no. 4 PHASE 2 / BUILD THE SKELETON

27a recipe book for everyone chapter no. 4 Cut the central tube to the required height for the device. (Make sure it fits perfectly with the other central tubes of any additional modules). Using a drill, drill holes along the length of the tube. The diameter is the same of the bamboo canes. (Space them 2 cm vertically, and arrange it in a radial pattern around the tube). A) Prepare the Central Tube B) Drill Holes

28construction manual for a solitary bee house build the skeleton Insert the bamboo canes into the holes, making sure they are securely seated and won’t break (use the connectors to help you do this). Attach the central tube to the recovered base, which will act as a cap. C) Insert the Nesting Tubes D) Close the Device

29a recipe book for everyone chapter no. 5 Insert the complete structure into the mold you found, making the central tube comes out. E) Insert it in the Mold

30construction manual for a solitary bee house prepare your mycelium NECESSARY TOOLS : INGREDIENTS: Scissors Nitrile gloves (or plastic gloves) Spray bottle filled with Ethanol Tissues Hoven Bowl Pot Stove Rice straw Mycelium lavender seeds or similar CHAPTER no. 5 PHASE 3 / PREPARE YOUR MYCELIUM

31a recipe book for everyone chapter no. 5 Weigh the required amount of plant substrate. Boil the substrate to sterilize it. (Let it cool completely before proceeding). Prepare a clean workspace by sanitizing the surface with alcohol. In a clean bowl, combine the sterilized substrate, 10% of the mycelium weight, and 5 g of lavender seeds. A) Substrate Sterilization: B) Mycelium inoculation

32construction manual for a solitary bee house prepare your mycelium Mix the elements thoroughly in a bowl (make sure the substrate is moist but not wet, and there are no clumps of undistributed mycelium). Pour the composite into the mold, around the central structure. Place the mold in a dark or dimly lit environment. (Maintain 60% humidity for approximately 14 days. Tip: Place a basin of warm water next to the mold and replace it daily). Do not move or open the mold during this period. C) Mixing D) Composite Incubation

33a recipe book for everyone chapter no. 4 Wear clean gloves and remove the mold from the colonized composite. Transfer the mold to the oven at 60°C for 24 hours. Allow the device to cool. (Make sure the weight remains stable to confirm the mold is completely dry). E) Composite Inactivation F) Bring Out

34construction manual for a solitary bee house final assembly At this point, you can either stack multiple modules (thanks to the interlocking central tubes) or use the device individually on a raised pedestal. Note: On the ground, the device will degrade within 1 year (rapid regeneration). Raised on a pedestal, it will last 2–3 years before starting to decompose. A) Choose your configuration CHAPTER no. 6 PHASE 4 / FINAL ASSEMBLY

35a recipe book for everyone chapter no. 6 Bring the devices to the chosen plot. Place them in sunny or partially shaded areas. Maintain a consistent distance between each module (1 every 10–20 m²). Let solitary bees colonize the cavities independently. B) Installation on the plot

36construction manual for a solitary bee house final assembly Let the device do its job and after a few months... or years come back to see the transformation! year 0 after 6 month after 1 years C) Let it grow

37a recipe book for everyone chapter no. 6 after 1.5 years after 3 years

POLITECNICO DI MILANO School of Design Department of Architecture, Built environment and Construction engineering ATELIER FOR TECHNOLOGIES: Culture & Practice of Design Technologies A.Y. 2025-2026 Professors: Prof. Arch. PhD. Alessandra Zanelli Prof. Arch. Luca Medioli Arch. Haya Alhussaini The Inter-Departmental Laboratory on Textiles materials and Polymers @PoliMi

Students: Giulia Brambilla, Martina Maria Martin, Lucia Mella, Erseda Skenderaj, Camilla Truffelli, Alice Ucciardo