070 - Seismic Irregularities: Soft Story to Shear Walls

070 - Seismic Irregularities: Soft Story to Shear Walls

Soft story buildings are one of the most dangerous structural conditions in seismic design, and the 1994 Northridge earthquake proved why. In this episode, we break down the seismic irregularities that cause buildings to fail during earthquakes. You will learn the difference between a soft story and a weak story, how geometric and mass irregularities create dangerous force concentrations, and why a broken load path is the most dangerous irregularity of all. We also cover re-entrant corners, torsional irregularity, rigid vs flexible diaphragms, and how collectors and drag struts keep the lateral load path connected. Then we walk through the exam strategy: red flags to watch for, common fixes including moment frames, braced frames, and seismic joints, and the one principle NCARB keeps coming back to. Eliminate the irregularity entirely rather than engineering around it. 📝 Key topics covered: * Soft story buildings and the 1994 Northridge earthquake * Soft story vs weak story: bending vs breaking * Building drift and the 70% stiffness threshold * Vertical geometric irregularity and building setbacks * Mass irregularity and heavy mechanical floors * Continuous load path: roof to diaphragm to shear walls to foundation * In-plane discontinuity vs out-of-plane offset * Collectors and drag struts * Rigid vs flexible diaphragms * Re-entrant corners in L-shaped and T-shaped buildings * Torsional irregularity: center of mass vs center of rigidity * Moment frames vs braced frames * ARE exam red flags for seismic irregularities ⏱️ Chapters: 0:00) Soft Story Buildings and Northridge (1:40) Study Notes (3:26) Soft Story vs Weak Story (6:36) Geometric and Mass Irregularities (8:54) Load Path and Shear Wall Discontinuities (13:17) Re-Entrant Corners and Torsion (15:50) Seismic Irregularities on the ARE (18:32) Seismic Design Key Takeaways 📖 Read the full blog post and grab free study notes: Soft Story Building: Seismic Irregularities Explained [https://academy2.youngarchitect.com/soft-story-building-seismic-irregularities/] 📝 Free study notes for this episode: youngarchitect.com/seismic [https://youngarchitect.com/seismic] 🎯 ARE 101 Membership (access all courses) [https://academy2.youngarchitect.com/are-study-materials/] 🎯 ARE Boot Camp (10-week coaching program) [https://youngarchitect.com/arebootcamp/] 📚 Individual ARE Exam Courses: * PPD 101 (Project Planning and Design) [https://academy2.youngarchitect.com/are-project-planning-and-design/] * PDD 101 (Construction Documents and Specs) [https://academy2.youngarchitect.com/are-project-development-and-documentation/] * Building Codes 101 [https://academy2.youngarchitect.com/are-building-codes-101/] * PA 101 (Programming and Analysis) [https://academy2.youngarchitect.com/programming-analysis-101-are-5-0-exam-prep/] * CE 101 (Construction and Evaluation) [https://academy2.youngarchitect.com/are-construction-and-evaluation/] * Mechanical Systems 101 [https://academy2.youngarchitect.com/are-mechanical-systems-101/] * PcM 101 (Practice Management) [https://academy2.youngarchitect.com/are-practice-management/] * PjM 101 (Project Management) [https://academy2.youngarchitect.com/are-project-management/] * AIA Contracts 101 [https://academy2.youngarchitect.com/are-aia-contracts-101/] * CDT 101 (Construction Documents Technologist) [https://academy2.youngarchitect.com/cdt-exam-prep/] * CCCA 101 (Construction Contract Administration) [https://academy2.youngarchitect.com/ccca-exam-prep/]

069 - Sealant Types, Backer Rod, and Joint Design for Buildings

Which sealant goes where on the building envelope? This episode covers every sealant type, backer rod, and how to design joints that actually work. We break down the five main sealant families: silicone, polyurethane, polysulfide, acrylic, and MS polymer. Each one has a personality, a best use, and a catch. You'll learn why silicone can't be painted, why polyurethane hates UV, why polysulfide smells like rotten eggs, and when MS polymer gives you the best of both worlds. Then we get into joint design, because even the best sealant fails if the joint is wrong. We cover backer rod (open cell vs. closed cell), the width-to-depth ratio that makes or breaks a sealant joint, tooling, and the number one joint design failure: three-sided adhesion. 📝 Key topics covered: * Silicone sealant: acetoxy vs. neutral cure and when each one matters * Polyurethane sealant for concrete expansion joints and window perimeters * How backer rod controls depth and prevents three-sided adhesion * The hourglass profile and why sealant joint geometry matters * Adhesion failure vs. cohesion failure: two ways sealants break * Sealant vs. caulk: what's the actual difference ⏱️ Chapters: (0:00) Why Sealants Matter Most (0:50) Free ARE Study Notes (1:22) Sealant vs. Caulk (2:26) Sealant Movement and Failure Modes (4:33) John Hancock Tower Sealant Failure (5:35) Silicone Sealant: The Diva (8:22) Polyurethane Sealant: The Workhorse (10:17) Polysulfide Sealant: The Hazmat Suit (11:39) Acrylic Sealant: The Weekend Warrior (12:45) MS Polymer Sealant: The Hybrid (13:48) Sealant Selection Cheat Sheet (14:26) Butyl and Acoustical Sealant (15:36) How to Design a Sealant Joint (15:57) Backer Rod (17:43) Sealant Joint Width and Depth (20:00) Three-Sided Adhesion (21:11) Sealant Speed Round (22:32) NCARB Exam Connections (23:27) Sealant Recap (24:44) Young Architect Academy 📖 Read the full blog post [https://academy2.youngarchitect.com/sealant-types/] 📝 Download the FREE Sealant study notes [https://youngarchitect.com/sealant] 🎯 Get access to all ARE study materials with the ARE 101 Membership [https://academy2.youngarchitect.com/are-study-materials/] 🎯 Join our 10-week ARE Boot Camp [https://youngarchitect.com/arebootcamp/] 📚 Individual courses: * PDD 101 (Construction Documents and Specs) [https://academy2.youngarchitect.com/are-project-development-and-documentation/] * PPD 101 (Project Planning and Design) [https://academy2.youngarchitect.com/are-project-planning-and-design/] * Building Codes 101 [https://academy2.youngarchitect.com/are-building-codes-101/] * CDT 101 (Construction Documents Technologist) [https://academy2.youngarchitect.com/cdt-exam-prep/]

068 - Project Delivery Methods: DBB, Design-Build, CMAR, and More

Project delivery methods define who holds the contracts, who carries the risk, and how the architect's role changes on every construction project. This episode breaks down all six major methods so you know exactly how each one works. Emily walks through Design-Bid-Build, Design-Build, Construction Manager at Risk (CMAR), Construction Manager as Agent (CMa), Multiple Prime, and Integrated Project Delivery (IPD). You'll learn why the architect works for the owner in some methods and for the contractor in others, what a GMP contract actually does, and how to match the right delivery method to a project scenario on the ARE. This topic shows up on three different ARE exams and the CDT exam. If you invest the time to learn it now, it pays off on every exam you take. 📝 Key topics covered: * Design-bid-build: the traditional sequential method * Design-build: one team, one contract, architect works for the contractor * CMAR and GMP contracts: how the CM shifts from advisor to constructor * CM at risk vs CM as agent: who holds the subcontracts * Fast-tracking: a scheduling technique, not a delivery method * Progressive design-build, design assist, and bridging ⏱️ Chapters: (0:00) What Are Project Delivery Methods (2:48) How Delivery Methods Hit the ARE (4:39) Design-Bid-Build Explained (6:16) DBB Pros and Cons (7:22) Who Holds the Risk in DBB (8:24) Design-Build Explained (9:36) Architect's Role in Design-Build (10:18) Fast-Tracking in Design-Build (12:33) DB Pros and Cons (13:32) Progressive Design-Build (14:11) Design Assist and Bridging (16:03) Construction Manager at Risk (16:55) What Is a GMP Contract (17:38) CMAR Phase Shift Explained (19:54) CMAR Pros and Cons (22:05) CM at Risk vs CM as Agent (23:11) Construction Manager as Agent (27:44) Multiple Prime Contracts (30:28) Integrated Project Delivery (IPD) (33:18) How to Choose a Delivery Method (36:12) ARE Study Resources 📖 Read the full blog post [https://academy2.youngarchitect.com/project-delivery-methods/] 📝 Download the FREE Project Delivery Methods study notes [https://youngarchitect.com/Methods] 🎯 Get access to all ARE study materials with the ARE 101 Membership [https://academy2.youngarchitect.com/are-study-materials/] 🎯 Join our 10-week ARE Boot Camp [https://youngarchitect.com/arebootcamp/] 📚 Individual courses: * PcM 101 (Practice Management) [https://academy2.youngarchitect.com/are-practice-management/] * PjM 101 (Project Management) [https://academy2.youngarchitect.com/are-project-management/] * CE 101 (Construction and Evaluation) [https://academy2.youngarchitect.com/are-construction-and-evaluation/] * AIA Contracts 101 [https://academy2.youngarchitect.com/are-aia-contracts-101/] * CDT 101 (Construction Documents Technologist) [https://academy2.youngarchitect.com/cdt-exam-prep/]

067 - Types of Insulation: Materials, R-Values, and Assemblies

Types of insulation explained, from fiberglass batts to spray foam to rigid board to continuous insulation. This episode covers every major insulation type you need to know for the ARE exam and real-world practice. You'll learn how heat transfer works through buildings, then walk through each material one by one. Fiberglass vs mineral wool, open cell vs closed cell spray foam, EPS vs XPS vs polyiso, and why continuous insulation is the only way to solve thermal bridging. Every section connects back to how these materials behave in real wall assemblies, not just what their R-value is on a spec sheet. 📝 Key topics covered: * Fiberglass insulation vs mineral wool insulation * Open cell vs closed cell spray foam * EPS vs XPS vs polyiso rigid board insulation * Continuous insulation and thermal bridging * Blown-in insulation and dense pack cellulose * How insulation choice affects vapor management ⏱️ Chapters: (0:00) Introduction (1:48) Free Study Notes (3:07) How Heat Transfer Works (6:49) Fiberglass and Mineral Wool Batts (9:51) Blown-In Insulation (12:25) Spray Foam: Open vs Closed Cell (15.28) Rigid Board Insulation (17:58) Continuous Insulation (20:51) SIPs, ICFs, Radiant Barriers (22:54) Vapor Barriers and Insulation (24:15) Common Insulation Exam Traps (26:08) ARE Study Materials (27:14) Wrap Up 📖 Read the full blog post and grab free study notes: Types of Insulation: Materials, R-Values, and Assemblies [https://academy2.youngarchitect.com/types-of-insulation/] 📝 Free 2-page insulation study notes: youngarchitect.com/insulation [https://youngarchitect.com/insulation] 🎯 ARE 101 Membership (access all ARE courses) [https://academy2.youngarchitect.com/are-study-materials/] 🎯 ARE Boot Camp (10-week coaching program) [https://youngarchitect.com/arebootcamp/] 📚 Individual courses: * PPD 101 (Project Planning and Design) [https://academy2.youngarchitect.com/are-project-planning-and-design/] * PDD 101 (Construction Documents and Specs) [https://academy2.youngarchitect.com/are-project-development-and-documentation/] * Building Codes 101 [https://academy2.youngarchitect.com/are-building-codes-101/] * Mechanical Systems 101 [https://academy2.youngarchitect.com/are-mechanical-systems-101/] * CDT 101 (Construction Documents Technologist) [https://academy2.youngarchitect.com/cdt-exam-prep/] * PA 101 (Programming and Analysis) [https://academy2.youngarchitect.com/programming-analysis-101-are-5-0-exam-prep/] * CE 101 (Construction and Evaluation) [https://academy2.youngarchitect.com/are-construction-and-evaluation/] * PcM 101 (Practice Management) [https://academy2.youngarchitect.com/are-practice-management/] * PjM 101 (Project Management) [https://academy2.youngarchitect.com/are-project-management/] * AIA Contracts 101 [https://academy2.youngarchitect.com/are-aia-contracts-101/]

066 - Types of HVAC Systems and How to Choose

There are a lot of different types of HVAC systems, and if you're studying for the ARE or coordinating with mechanical engineers, you need to know what each one does and when to use it. In this episode, Layla breaks down every major HVAC system type into four categories: all-air, water-based, refrigerant-based, and packaged systems. She covers VAV, fan coil units, VRF, rooftop units, PTACs, radiant floor heating, chilled beams, DOAS, split systems, and more. Then she walks through how to match each system to different building types, which is exactly how the PPD and PDD exams test this material. If mechanical system questions have been tripping you up, this one's for you. 📝 Key Topics Covered: * VAV systems: the workhorse of commercial office buildings * Fan coil units: individual room control for hotels and apartments * VRF systems: flexible refrigerant-based zoning for mid-rise and retrofit projects * Rooftop units and PTACs: simple packaged systems for retail and hotels * Radiant floor heating: when forced air can't reach the occupants * DOAS: why ventilation gets its own dedicated system * Matching HVAC systems to building types for the ARE ⏱️ Chapters: (0:00) Introduction (2:32) How to Think About HVAC (4:17) All-Air Systems (7:47) Water-Based Systems (10:32) Packaged and Refrigerant Systems (13:13) Matching Systems to Buildings (18:22) Wrap Up 📖 Read the full blog post with diagrams and a building-type matching table: Types of HVAC Systems and How to Choose [https://academy2.youngarchitect.com/types-of-hvac-systems/] 📝 Download the free HVAC study notes: Free HVAC Study Notes [https://youngarchitect.com/hvac] 🎯 Join ARE Boot Camp, our 10-week coaching program: ARE Boot Camp [https://youngarchitect.com/arebootcamp/] 📚 Get access to all ARE courses with the ARE 101 Membership: ARE 101 Membership [https://academy2.youngarchitect.com/are-study-materials/] Individual ARE and CSI Exam Courses: * Mechanical Systems 101 [https://academy2.youngarchitect.com/are-mechanical-systems-101/] * PPD 101 (Project Planning and Design) [https://academy2.youngarchitect.com/are-project-planning-and-design/] * PDD 101 (Construction Documents and Specs) [https://academy2.youngarchitect.com/are-project-development-and-documentation/] * Building Codes 101 [https://academy2.youngarchitect.com/are-building-codes-101/] * CDT 101 (Construction Documents Technologist) [https://academy2.youngarchitect.com/cdt-exam-prep/] * CCCA 101 (Construction Contract Administration) [https://academy2.youngarchitect.com/ccca-exam-prep/] * PcM 101 (Practice Management) [https://academy2.youngarchitect.com/are-practice-management/] * PjM 101 (Project Management) [https://academy2.youngarchitect.com/are-project-management/] * CE 101 (Construction and Evaluation) [https://academy2.youngarchitect.com/are-construction-and-evaluation/] * PA 101 (Programming and Analysis) [https://academy2.youngarchitect.com/programming-analysis-101-are-5-0-exam-prep/] * AIA Contracts 101 [https://academy2.youngarchitect.com/are-aia-contracts-101/]