This package combines two of our most sought-after resources — the House Extension Details book and the Building Regulations Notes Template — now available together at a discounted price.
The House Extension Details book gives you a library of ready-to-use, fully annotated 2D and 3D construction details covering standard junctions, materials and extension configurations. It's designed to streamline your drawing production and eliminate the time spent redrawing common technical details.
The Building Regulations Notes Template is a comprehensive, editable set of Building Regulations drawing notes, created to save you time and give you a reliable starting point for domestic projects. The notes are split into two documents, one for Extensions and Alterations which is an 80 page document. The second option is for Extensions, Alterations and Conversions, which is a 137 page document.
Together, these resources give you both sides of the technical process — clear, well-resolved construction details and a structured set of Building Regulations notes to support your submission.
The book helps you develop and coordinate your drawings with confidence, while the notes template provides a consistent framework for addressing statutory requirements, Part L compliance, and project responsibilities.
Used alongside one another, they help reduce duplication, avoid inconsistencies between drawings and notes, and support smoother Building Control submissions on domestic extension projects.
About House Extension Details - An Architectural Guide
[Published June 2025]
A must-have resource for architects working on residential projects, House Extension Details offers an extensive collection of construction drawings and guidance designed to support your design and detailing process from planning to completion.
Get the full experience with our complete digital toolkit for house extensions. This all-in-one bundle includes the PDF House Extension Details Book, CAD details, and 3D SketchUp models—giving you everything you need to visualise, communicate, and construct with confidence.
Explore 3D models of real-world construction details, adapt CAD files to your workflow, and gain a clear roadmap from concept to delivery.
📐 What’s in the Book?
- A comprehensive library of 200+ 2D and 3D construction details: walls, foundations, floors, roofs, thresholds, doors, windows, and more
- Multiple build-ups including timber frame, masonry cavity, solid wall retrofits, and low-carbon detailing strategies
- Clear annotation and practical context for how and when to apply the details
- Real-life project guidance, including regulatory considerations, material selection, and sequencing tips
🛠️ Designed For
- Sole traders and small practices needing reliable detailing references
- Architects looking to streamline technical design stages without compromising quality
- Practices working with retrofits, heritage buildings, or tight urban sites where custom detailing is key
What do I get?
House Extension Design – A Practical Guide for Architects Bundle 3 includes:
PDF file of the book
2D details in CAD format as dwg files (AutoCad 2010)
3D details in SKP format for SketchUp (version 2024)
Details drawn in metric units
PLUS:
Extension Example Planning Drawing Set
Extension Example Stage 4 / 5 GA Drawing Set
U-Value Quick Reference Guide
Measured Survey Checklist
House Extension Planning Process Checklist
House Extension Fire Safety Checklist
RIBA Plan of Work House Extension Checklist
Perfect for: Architects looking for the full toolkit to help run their extension projects with ease, precision and speed.
How do I get it?
After purchase you will receive an email confirming your order along with the download link to get your book – so please make sure you enter your email address correctly.
Please check your junk or spam folders. If you haven't received your link after about 10 minutes, please contact us.
System Requirements: Please note this package includes a pdf file which is large in size. Make sure you have a good internet connection, and download the file to a laptop or pc for best results.
The CAD Details
In addition to the PDF file of the book, bundle two gives you all of the 2D CAD details that are featured in the book.
We also provide the .ctb plotstyle file so that you can easily print the details in the same style as seen in the book.
The CAD details are provided in .dwg format, suitable for use in AutoCAD version 2010 or more recent.
All the CAD details at your fingertips to explore and edit.
The SketchUp Files
Bundle 3 also includes the SketchUp models. The models are easily editable and compatible with version 2022 of SketchUp and any later versions.
This is a great opportunity to explore the 3d details and understand how the detail is put together. Each detail is saved with it's own scene so you can easily navigate through the model files.
Plenty of 3D magic for you to enjoy!
Extra Bonuses!
Bundle 3 includes some extra bonuses that we have put together to help you along with your extension projects.
- Extension Example Planning Drawing Set
- Extension Example Stage 4 / 5 GA Drawing Set
- U-Value Quick Reference Guide
- House Extension Fire Safety Checklist
- Measured Survey Checklist
- Planning Process for House Extensions
- RIBA Plan of Work Checklist for House Extensions
Testimonials
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.
Liam Briggs - Chartered Architectural Technologist
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!
Sonia Brookes - Architect
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.
Joe Hyett - Chartered Architectural Technologist
Wow, what a great book for the UK market! This is the best book for anyone struggling to understand extensions. Well done guys, you nailed it.
Sonda Mvula - Architectural Designer and Director
About the Building Regulations Notes Template
Typical Building Regulations Notes For Domestic Extensions, Alterations & Conversions
A comprehensive, editable set of Building Regulations drawing notes, created to save you time and give you a reliable starting point for domestic projects.
The notes are split into two documents, one for Extensions and Alterations which is an 80 page document. The second option is for Extensions, Alterations and Conversions, which is a 137 page document.
The documents are designed for architects, architectural technologists and designers working on UK house extensions, loft conversions, garage conversions and internal alterations. They provide a structured framework of Building Regulations notes that can be tailored to suit individual projects and Building Control requirements.
Supplied as two editable Word documents and two PDFs, the notes can be quickly adapted to suit different schemes, local authority preferences and project-specific constraints.
What's included?
This product includes professionally structured Building Regulations drawing notes, supplied as editable Word documents and written specifically for UK domestic projects.
Two documents:
- Extensions & Alterations – approx. 80 pages
- Extensions, Alterations & Conversions – approx. 137 pages
Both versions are designed to be edited and adapted to suit individual projects and Building Control requirements.
Regulatory context and responsibilities
Clear notes covering the wider statutory framework around domestic projects, including:
- Planning consent and conditions
- Building Regulations approvals and inspections
- Building Safety Act 2022 duties
- CDM Regulations 2015
- Party Wall etc. Act 1996
- Shared drainage and Water Industry Act requirements
Site, client and contractor information
Practical notes to support clarity and risk management on site:
- Client and contractor responsibilities
- Site assessment and investigation
- Demolition and existing structure considerations
- Materials, workmanship and UK standards
- Extreme weather and coastal location guidance
Fabric performance and Part L guidance
Detailed coverage supporting Building Regulations compliance, including:
- Thermal bridging, airtightness and condensation control
- New and retained thermal elements
- U-value tables for extensions, conversions and upgrades
- 25% glazing rule, SAP implications and exemptions
Structure and construction elements
Project-ready notes covering typical domestic construction, including:
- Structural coordination and engineer responsibilities
- Foundations, floors, walls and roofs
- Windows, doors, staircases and guarding
- Drainage, fire safety, services and ventilation
- External works and renewable energy
How you should use the notes
- As a starting point for your own project-specific Building Regulations notes
- Edit and adapt to reflect the drawings, specification and site conditions
- Review and amend to suit the latest Building Regulations and Approved Documents
- Coordinate with your structural engineer’s design and any specialist reports
The documents are intentionally detailed, but are not project-specific and should never be used without review and amendment.
Can it be used for new build?
The documents are set up specifically for extensions, alterations and conversions. However, because it is supplied as an editable Word document, users can adapt them for new-build projects by adding the relevant sections themselves if they wish.
⚠️ Important limitations and disclaimer
These notes documents are intended as base documents only. They are not project-specific and must be edited and amended to suit the drawings, specification and site conditions of each individual project.
By purchasing these documents, users accept that they remain fully responsible for researching, interpreting and complying with the current Building Regulations and all related legislation. The documents do not guarantee Building Control approval and do not remove the need for professional knowledge or experience.
The notes are designed for domestic extensions, alterations and conversions only. They are not suitable for basements, non-domestic work or new-build projects without significant amendment. No updates or ongoing support are provided.
What you’ll receive
- 2 × fully editable Word (.doc) documents
- 2 x PDF documents
- Immediate digital download after purchase
Format and flexibility
- Supplied as fully editable Word (.doc) documents
- Written for domestic extensions, alterations and conversions
- Intended as a starting point, not a fixed specification
Who this is for
- Architects and architectural technologists
- Designers preparing Building Regulations submissions
- Practices looking to standardise their domestic project notes
- Anyone wanting a clear, organised starting point rather than writing notes from scratch
Who this is not for
- Anyone looking for a “plug and play” specification
- Users unfamiliar with the UK Building Regulations
- Projects outside domestic extensions, alterations and conversions
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PRINT BOOKS COLLECTIONFrequently Asked Questions
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