Architects, Meet Your New Favourite Desk Companion.
We get it—residential extensions are rarely “straightforward.” From mismatched brickwork to head-scratching retrofit upgrades, you’ve seen it all. And after the fifth time redrawing a window detail on a Monday night, you might be wondering if there’s an easier way.
There is. It’s this book.
House Extension Details is packed with the technical knowledge and construction drawings you need to get the job done—accurately, efficiently, and without reinventing the wheel (again).
Created by architectural professionals for architectural professionals, this guide focuses on what matters most—technical clarity, real-world applicability, and time-saving resources you can trust. Whether you’re a sole practitioner juggling multiple roles or part of a small studio delivering bespoke domestic extensions, this book equips you with the tools to work smarter and with greater confidence.
What You’ll Get
- A comprehensive library of 200+ 2D construction details: walls, foundations, floors, roofs, thresholds, doors, windows, rooflights and more
- Multiple build-ups including timber frame, masonry cavity, solid wall retrofits, and structural glazing detailing strategies
- Clear annotation and practical context for how and when to apply each detail
- CAD and SketchUp files available in bundled formats for seamless integration into your workflows
- Example planning and technical drawing packs
- Real-life project guidance, including regulatory considerations, material selection, and detail design tips
️ Designed For
- Sole traders and small practices needing reliable detailing references
- Architects looking to streamline technical design stages without compromising quality
- Young architects looking to broaden their construction detailing knowledge
This book isn’t just a collection of drawings—it’s a working reference designed to support the realities of architectural practice. Save time on every project, enhance design quality, and gain confidence in your detailing decisions.
See the Book for Yourself – Download a Free Sample
Curious about what’s inside? We’re offering a free sample of House Extension Details: An Architectural Guide so you can experience the quality and depth of content first-hand.
Inside the sample, you’ll find practical examples, expert construction details, and a full index of the 200+ details inside.
Discover why architects will be calling this an essential reference for house extensions.
Here’s What Makes It Awesome.
This isn’t a dusty textbook or a vague “design inspiration” guide. It’s a real-world tool for real-world architects.
You’ll get clear drawings, smart commentary, and loads of guidance to help you create extensions that work—structurally, aesthetically, and thermally.
We’ve even included multiple insulation strategies, cavity options, and material pairings—so you’re covered whether you’re working on a dreamy garden studio or a challenging retrofit on a semi with five previous owners and no straight lines.
Choose the Right Bundle for You.
We’ve created three flexible bundles to suit the way you work — whether you want quick inspiration or a full set of resources to power your next project. Select your bundle and get started today!
Bundle 1
Book PDF- Book in PDF format
- Over 200 2D details
- Over 200 3D details
Book PDFBundle 3
- Complete Resource Pack
- Book in PDF format
- Over 200 2D details
- Over 200 3D details
- CAD files for every detail included in the book
- SketchUp files for 3D modelling
- And more useful resources!
Bundle 2
- Book PDF + CAD Files
- Book in PDF format
- Over 200 2D details
- Over 200 3D details
- CAD files for every detail included in the book
Book PDF + CAD FilesMeet the Authors
Emma Walshaw
Emma is the founder of First In Architecture and author of several construction detailing books. Emma has spent years helping architecture students and professionals deepen their understanding of construction detailing. Her work is driven by a desire to make complex information accessible and to support others in their learning journey.
In this collaboration with Aida, she continues her mission to provide architects with the tools they need to produce detailed, effective designs.
Aida Rodriguez Vega
Aida is an experienced architect with a strong background in technical detailing and high end residential projects. Drawing from her practical experience, Aida brings a comprehensive and meticulous approach to the content in this book.
She is passionate about bridging the gap between theoretical knowledge and real-world application, and has worked closely with Emma to develop a resource that is both informative and immediately useful for anyone working on house extensions.
Emma’s Books Have Been Featured On
Praise for the Book
Encyclopaedic in its depth and completely unique and comprehensive. It should be an ally to any architectural designer – student or experienced professional. This is the best piece of architectural writing I’ve seen, if only I had this a decade ago throughout my university years – a lot of mistakes would’ve been avoided. Incredible work.
A clear, beautifully presented technical resource and an invaluable reference for designers working in residential settings. It’s accessible at all levels – starting from first principles and expanding into detailed design thinking through the chapters. A fantastic, comprehensive guide – truly an extension bible!
The book’s thoroughness is truly impressive. Each detail is carefully broken down with clear explanations, well-cited sources and visually compelling 3D illustrations. It succeeds in taking a complex subject and presenting it in a format that is both accessible and easy to understand.
Frequently Asked Questions
What exactly is included in each bundle?
Each bundle is clearly outlined above — but in short: Bundle 1 gives you the full PDF book, Bundle 2 adds editable CAD files of all the details, and Bundle 3 includes everything from Bundle 2, plus SketchUp files, example drawing sets, a U-value guide, and more resources coming soon.
Can I use the CAD and SketchUp files for my own projects?
Yes! The files are designed to save you time. You can adapt them for your own house extension designs — just make sure all work is checked and approved by a qualified professional before use.
Are the details compliant with Building Regulations?
The details have been prepared by experienced architects and align with current UK Building Regulations at the time of publication. However, as every project and site is different, it’s essential to use them as a guide and always verify compliance with your project’s specific requirements and local authorities.
Is this book suitable if I'm still a student?
Absolutely. The book is designed to be accessible for students, graduates, and practicing architects alike. It breaks down complex topics and provides step-by-step detail examples to help build your technical knowledge and confidence.
How do I receive the files after purchase?
All files are available for instant download after checkout. You’ll also receive an email with links to your downloads, so you can access them any time.
Will there be updates to the resources?
Yes! Bundle 3 owners will automatically receive any new resources we add in the future (such as additional guides and templates) at no extra cost.
What if I have questions or need support?
We’re here to help. Just get in touch through our contact page and we’ll do our best to support you — just like a friend in the studio would.
What makes it worth the price?
Compared to the time you would spend researching, drawing, and checking details yourself — these resources offer massive value. Plus, they’re created by architects with real-world experience in house extensions.
How is this different from other detail books I already have?
This guide is tailored specifically for modern house extensions in the UK, not generic construction. It focuses on practical, adaptable details you can use right away, with CAD and SketchUp files ready to integrate into your own projects.
Will I actually use the CAD and SketchUp files?
If you ever need to produce or check extension details, these files will save you hours. You can customise them, learn from them, or use them as a starting point for your own projects.