JOONAS CASTRÉN
Portfolio
MSc: TU Delft
BSc: University of Virginia
CONTENTS:
01: Mandi Trade Corridor | market
02: Urban Canopy | school
03: WAM architecten | various
04: Rapid Shelter | tiny housing
05: Courtyard Commons | mixed-use residential
appendix: architectural engineering & modelmaking
EDUCATION:
MSc Architecture candidate:
Delft University of Technology, (Delft, Netherlands)
August 2023 - Current
B.S. Architecture & B.A. Global studies: University of Virginia, (Charlottesville, VA)
August 2018 - May 2022
PROFESSIONAL EXPERIENCE:
Design Intern: WAM architecten, (Delft, Netherlands)
July 2024 - Current
Lance Corporal: Finnish Defence Forces, (Vekaranjärvi, Finland)
July 2022 - March 2023
Assistant video producer:
The University of Virginia Darden School of Business, (Charlottesville, VA)
September 2019 - May 2022
Winter intern: Studios Architecture, (Washington, D.C.)
January 2022
Winter intern: Quinn Evans Architecture, (Washington, D.C.)
January 2020
SKILLS:
Graphics: Revit | Adobe Suite | AutoCAD
3D Modeling: Rhinoceros 3D | Grasshopper | SketchUp | Twinmotion | V-Ray
Languages:
English (native/fluent) | Finnish (native/fluent) | Spanish (A2)
Joonas Castrén
01: Mandi Trade Corridor
Market, (UVA): Fall ‘21, BS. Arch.
Instructors: Pankaj Vir Gupta & M. G. Aranguren Collab.: mapping & landscape with Fanke Su, research with Oliver Church
This project reimagines the mandi, a traditional agricultural marketplace, by integrating civic spaces like clinics, schools, and government offices to foster urban-rural exchange. It serves as a sustainable and community-focused addition to Jaipur’s urban fabric.
Informed by months of interdisciplinary research, the design process involved GIS mapping, discussions with local decision-makers, and film studies to understand Jaipur’s layered challenges, including water scarcity, rural poverty, and social divides.
Aerial view Joonas
The mandi master plan proposes trade hubs at key nodes along NH-52, a northsouth highway that divides the urban and rural regions. Along with anganwadis (rural child care centers), cold storage facilities, and afforestation sites west of the highway, the project is a holistic response to improve Jaipur’s social and ecological resilience.
Plaza view
Mandis along Jaipur urban edge (w/ Fanke Su)
Circulation
Pedestrian - Ground floor
Program
Produce
Pedestrian - Second floor Vehicle Waste collection Waste water Waste water- underground
Design sketches & concept diagrams
The trade hub softens the intensity of the highway’s edge by routing heavier traffic through service lanes. Pedestrians can safely gather, cross the highway, and circulate through the building with a network of suspended catwalks. Sloped roofs collect rainwater into underground tanks for washing produce and operating public lavatories. Also, a bioremediation layer collects rainwater during the monsoon season.
Joonas Castrén
Top view
Silo
Capacity: ~ 250-750 tonnes
Materials: metal
Perishability: low
Cover and plinth (cap)
Capacity: ~ 50-500 tonnes
Materials: concrete, earth, polyethylene
Perishability: moderate
Tractor-pulled trailer
Capacity: ~ 1- 10 tonnes
Avg. speed: ~20-27 km/h
Typical use: transport goods over moderate to long distances on intermediate to major roads.
area
Rural farm case study
Alternative configurations along National Highway - 52
02: Urban Canopy
School, ( TU Delft): Fall ‘23, MSc. Arch. Instructor: Job Schroën
The Urban Canopy combines a community school and bazaar in Antakya, the epicenter of the 2023 Turkey-Syria earthquakes. It integrates earthquake-resilient techniques and local needs within Foster + Partners’ reconstruction masterplan.
Located at the crossroads of the Roman city center, mixed-use housing, and cultural districts, the design features rammed-earth cubes beneath a highperformance space-frame roof. This creates a comfortable microclimate suited to Antakya’s Mediterranean-like conditions. The materials, chosen for their cooling properties and support of local suppliers, reinforce the city’s shared heritage across religious and ethnic groups.
Joonas Castrén
Pedestrian street elevation
Regional analysis
Medium % damage, medium population
High % damage, high population Urban areas
Aerial view
During the evening and weekends, the school opens up to the community. The cafeteria and bazaar stalls sell baked goods for locals and tourists. For safety during the schoolday, sectors are closed-off and students can travel between classrooms with an elevated catwalk, supported by branching tree-like columns.
Ground plan
WC
Grades
Cafeteria
Grades
Babies’
Toddlers’
Storage
Grades 5-6
Presentation
Bazaar rooms
Library
Storage
Storage
Gym & stage
Counselor & offices
Teacher’s lounge
Impression of rammed earth classrooms
Concept diagram
Joonas Castrén
Earthquake-resilient joinery case study
(w/ Gijs van der Kerk & Joyce de Louw)
1:20 section fragment of school building
Structural section
1. Upper chord member
2. Photovoltaic panel & mounts
3. Mount for polycarbonate panel
4. Bottom chord member
5. Mero-system node
6. Bolt
7. Metal plate
8. Straps for cable bridge
9. Hanger straps
10. Excess heat duct
11. Corten steel branching column
12. Storm water pipe
13. Tensioned steel cables
14. Bridge deck
15. Ramp with hinge
16. Ceiling frame
17. Double-glazed window
18. Bond beam
19. Anchoring bolts
20. T-shaped steel bar
21. Stabilized rammed earth wall
22. Rebar
23. Insulation
24. Interior finish
25. Door lintel
26. Metal-glass door
Joonas Castrén
03: WAM architecten
Various projects, (internship):
Supervisors: Wilfried van Winden & Silvia Leone
At WAM architecten, I contribute to projects of various scales and phases which are primarily residential. As an intern, I assist principal architects in visualizing design intent, making design suggestions, and identifying potential issues during archival drawing analysis. The firm’s small size allows me to engage in diverse tasks, fostering continuous learning.
Included here are pieces from three projects: first Kuyperwijk Phase 3, a four-story apartment complex on Van Groenewegenstraat in Delft, secondly Klinkerbuurt Phase 4, terraced houses within a garden-city-inspired development at Schoemakerplantage, and finally an interior refurbishment for a branch of ING bank in Delft.
Joonas Castrén
Facade renovation - Kuyperwijk apartments (role: design visualization)
Wall details - Kuyperwijk apartments (role: design visualization)
This project involved the interior reconfiguration of an ING office in Delft, aimed at optimizing employee circulation and upgrading facilities. My role focused on updating the existing floor plan to reflect proposed changes, particularly in the heating and electrical systems, incorporating feedback from the principal architect and client.
Joonas Castrén
Plan - ING office
(role: editing construction documents)
Klinkerbuurt is a compact, zero-energy neighborhood in Delft, featuring carfree streets, communal courtyards, and Delft-style sidewalks that mediate between private and public space. My role primarily involved adapting standard floor plans from the contractor to align with the design, and revising the master plan yield study. This included contractor feedback to adjust the scale, number, and layout of units.
Typical floor plans & elevation: Klinkerbuurt terraced housing (role: design visualization)
Master plan - Klinkerbuurt terraced housing (role: conceptual diagrams, design visualization)
04: Rapid Shelter
Tiny housing, (UVA): Spring ‘21, BS. Arch
Instructor: Earl Mark & Phoebe Crisman
Shishmaref, a remote Alaskan village, faces relocation due to rising sea levels and thawing permafrost. This project explores culturally and climatically responsive housing for Arctic communities adapting to climate change.
Developed through a Global Studies capstone and an architecture elective on deployable shelters, the prototype serves multiple lives— first as transitional housing during construction, then as a hunter’s hut. Designed for resilience, it balances mobility, insulation, and traditional building practices. The research also examines best practices for designing adaptable, community-driven relocation strategies.
1. Weather-proof roof finish
2. Insulated structural panel (ISP) roof
3. Window frame
4. Opaque retractable curtain
5. Semi-opaque retractable curtain
6. Curtain handle
7. Transparent plastic window
8. Ply-wood floor finish
9. Glu-lam beam
10. Insulation
11. Collapisble frame
12. Cavity for running utilities
13. Removable step ladder for porch
14. Collapsible trusses of cribbing foundations
15. Gravel base
Shishmaref’s shifting permafrost and harsh winds require a lightweight, adaptable structure, much like traditional Qarmaqs. The prototype features adjustable cribbing foundations to thermally separate it from the ground and remain level despite soil movement.
Plan & transportation
1. Delivery to site
2. Maneuvering at site
3. Settlement
The shelter can be rapidly disassembled and moved along the coast or further inland to expand the range of fishermen and hunters. The base unit houses 1-2 adults but may be combined with other modules to suit families with children. The simple construction materials make it easy to customize, and the low profile counters high wind and snow loads.
Elevation & section
05: Courtyard Commons
Urban housing, (UVA): Spring ‘20, BS. Arch
Instructor: Anthony Averbeck
Richmond Loop(s) is a mixed-income housing project that bridges the carcentric north and pedestrian-focused south of E. Broad St., addressing the fragmentation caused by 1960s adhoc urbanism. Challenging the notion that urban housing must be hypercompact, it balances affordability, social interaction, and access to greenery within a non-hierarchical, mixed-use framework.
Elevating the building on a column grid frees the ground level for a public park, featuring a tree-lined corridor and reflecting pool. Bus riders, residents, and neighbors share this welcoming space, while an on-site market with direct transit access helps alleviate the area’s food desert conditon, reinforcing the project as a community anchor.
Joonas Castrén
Axonometric from northeast
Natural light is maximized by arranging the units in a loop around an interior courtyard. Along E. Broad Street, units are slightly set back to provide a buffer from traffic. Strategic cutouts reference the southern “porch culture” of singlefamily homes, fostering neighborly interactions and reducing the sense of isolation.
Plan of lower loop
Massing iterations
Circulation
Jurassic Arks (appendix):
Glass structures, (TU Delft): Spring ‘24, MSc. Arch.
Instructors: F.Oikonomopoulou, T. Bristogianni, James O’Callaghan
Collab: Marvin Cheng, Arian Babaei
The “Jurassic Arks” is an all-glass building designed to showcase dinosaur fossils at the Quarry Visitor Center in Utah. Its form, resembling a dinosaur rib cage, is embedded into the hillside.
The design challenges involved researching glass manufacturing constraints such as standard dimensions and exploring unconventional structural solutions. Structural integrity was finally verified using Karamba in Grasshopper.
Vertical glass fins are connected to horizontal panels with advanced hinge connections. A thin translucent layer of marble is laminated within the glass sheets to protect fossils from sunlight and create a sense of mystery and anticipation.
View on approach
Joonas Castrén
3.2 Panel Division - Fins
3.2 Panel Division - Fins
Structural verification & hand calculations
Fin division and structural analysis
The above diagram shows the key connections employed for the fins of the structure with expected moments and reactions.
Panel-panel connection
1. Heat-toughened annealed glass (8mm)
2. PVB layer (1,5mm)
3. Marble sheet (5mm)
4. Weather-proof cover
5. Hinge
6. POM wedge
7. Heat-toughened annealed glass (10mm)
8. Embedded titanium (3mm)
9. U-shape metal insert (2mm)
10. Countersunk bolt (ø 5mm)
11. Structural resin
12. PMMA pad (2mm)
Joonas Castrén
Solar Chimney (appendix):
Modelmaking, (TU Delft): Spring ‘24, MSc. Arch.
Instructors: E. Schreurs & P. Vermeulen
Collab: Ted van Duin, Yara Materman
Photography: Ruben Dario Kleimeer
In this 10-week “Material Lives” studio, my team and I explored a radical, climate-responsive addition to an aging school building in Rotterdam, addressing the local housing shortage. The existing structure is adapted into apartments on the upper floors, while the gymnasium is transformed into a dojo and community center.
The addition includes a gallery walkway that serves both as a spatial connector and a solar chimney, enhancing passive cooling in the summer and heat retention in the winter. We employed various model-making techniques to capture the existing brickwork, contrasting it with the design’s contemporary addition.
1:18 Fragment of intervention
mm x 410 mm x 865 mm
1:36 Intervention
210 mm x 460 mm x 400 mm
Window detail & massing study
(site model c/o Ziegler | Branderhorst)
The project began with a thorough analysis of archival drawings and site visits to authentically reconstruct the 1920s school building. This model was assembled collectively by the studio, where I was mainly responsible for digitizing the archival drawings, crossreferencing them with site photographs, and developing a precise Rhino model for the actual reconstruction.
1:36 Existing situation
1375 mm x 460 mm x 400 mm
JOONAS CASTRÉN
MSc Architecture candidate ‘25 (TU Delft) B.S. Arch. & B.A. Global Sustainability ‘22 (University of Virginia)