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House Extension Drawings — Builder Ready Plans, Done Online
Professional architectural drawings for your extension, from planning permission to building control — prepared remotely, fixed price, no jargon.
What our customers say
“Plan My Extension designed our project and were a pleasure to work with. They went through the whole process thoroughly from start to finish and nothing was too much trouble. They listened to our requirements and were able to offer excellent advice on what would work best to achieve a great design.”
“Thrilled to share my positive experience with Plan My Extension who crafted a brilliant extension plan. Their attention to detail, creativity, and professionalism exceeded my expectations. The design perfectly blends functionality with aesthetics, creating a space that truly feels like home.”
Planning Drawings
Floor plans and elevations, plus site and block plans, ready for submission to your local council.
Technical Drawings
Construction-ready floor plans, sections, and notes covering everything your builder needs.
Building Control Notes
Clear, compliant annotations covering materials, insulation, fire safety, and construction method.
Construction Details
Precise diagrams showing how key structural elements come together, helping avoid delays.
Complete PDF Pack
A full, planning-to-build documentation bundle — prepared remotely and delivered digitally.
The typical full service process:
Tell us about your project
Start by filling in a quick form to give us an idea of what you’re planning — whether it’s single-storey, two-storey or a porch. We’ll ask a few simple questions about your property and what stage you’re at so we can tailor your quote properly.
Get a fixed-price quote
Once we’ve reviewed your info, we’ll send you a no-obligation quote by email — quickly. You’ll see exactly what’s included, how the process works, and what you’ll get at each stage. No hidden costs or confusing terms, just clear pricing from the start.
We Prepare All Your Drawings
If you’re happy to move forward, we’ll guide you through a simple, remote survey. You can do it yourself or ask your builder to help — no site visits needed. Then we’ll get to work on your drawings, creating everything you need for planning permission or building control, depending on your package.
Have a question? It might be here.
Clear answers to help you plan with confidence.
Planning Permission is about how your extension looks and fits into its surroundings. The council checks things like:
-
the size and height of your extension
-
its design and appearance
-
how it affects your neighbours and the street scene
Building Regulations are about how your extension is built. They cover things like:
-
structural stability (will it stand up?)
-
fire safety
-
energy efficiency and insulation
-
ventilation, drainage, and access
In many projects you’ll need both — Planning Permission for approval to build, and Building Regulations to make sure it’s built safely and to standard.
Once you are happy to proceed, we’ll guide you through a simple, step-by-step process to kick things off.
We’ll ask for the following:
- Your name, contact details, and the address of the property
- Basic information about the property itself
- An overview of your goals — including your preferred style, estimated budget, and what you’re hoping to achieve
- Any timelines or deadlines you have in mind
- Survey information: floor plans, photos of the existing property, and any inspiration
If we need anything else before starting the design work, we’ll let you know right away.
It’s a free network of vetted local builders who we connect with homeowners once drawings are complete. Builders don’t pay fees; they simply recommend us in return.
We don’t take the full amount upfront. A deposit is paid once we’ve received your survey information, which allows us to programme your project into our schedule. The remaining balance is then split into clear, agreed milestones as we progress through your project — so you only pay as key stages are delivered.
Permitted Development rights are rules that allow you to make certain changes to your home without needing full planning permission. They cover common projects like small rear extensions, loft conversions, or adding a porch.
There are limits though — things like the size, height, and position of the extension all matter. If your home is in a conservation area, national park, or is a listed building, your permitted development rights may be restricted or removed entirely.
We’ll always check at the start whether your extension qualifies as Permitted Development or if a planning application is required, so you know exactly where you stand before moving forward.
On average, extensions range between £1,500 – £2,500 per m², but the exact cost will depend on factors like your chosen specification, location, and the complexity of the design.
Our detailed technical drawings make it easier for builders to provide accurate quotes. Beyond this, we can also work closely with our trusted network members to help optimise your design for buildability and budget — ensuring you get the most value from your extension without compromising on quality.
Plan my Extension is designed to make home design faster, simpler, and more affordable — without compromising on quality.
Unlike traditional practices, we operate fully online, which means no unnecessary site visits, meetings, or delays. You can manage your entire project from the comfort of your home, using our guided process and simple digital tools.
We also offer a unique self-survey model, allowing you to collect the necessary measurements yourself using our step-by-step instructions — saving time and reducing costs.
Plus, when your design is ready to build, we can connect you with our growing network of trusted local builders, helping you move from plans to construction with confidence.
In short, we’re here to make the home extension process smarter, more accessible, and tailored to modern homeowners.
You can’t upgrade from the Planning Package to the Full Package once work has started. However, you can purchase the Technical Package separately after planning is approved. Just keep in mind that you won’t benefit from the discounted rate that comes with choosing the Full Package upfront.
We’ve designed the process so you can carry out a measured survey yourself — no technical experience required.
As soon as you sign up with Plan my Extension, we’ll provide a clear, step-by-step guide showing you how to measure each room and take the key photos we need. You can use either a standard tape measure or a laser measure — whichever works best for you.
Once your measurements and photos are uploaded, our team will create accurate existing drawings to get your project underway.
Prefer to leave it to the pros? No problem — we’ll arrange for an approved builder from our network to carry out the survey for an additional fee.
Whichever route you choose, we’ll make sure you have everything needed to get started with confidence.
Not always.
At Plan my Extension, we’ll help you find out whether your project qualifies as permitted development — a set of rights that allow certain types of home improvements without needing full planning permission.
If your plans don’t meet the permitted development criteria, you’ll need to apply for planning permission. But don’t worry — we can guide you through that process too.
Even if planning permission isn’t required, we strongly recommend applying for a Lawful Development Certificate. This provides official confirmation that your project is permitted — and we’re happy to handle the application for you.
You can’t upgrade from the Planning Package to the Full Package once work has started. However, you can purchase the Technical Package separately after planning is approved. Just keep in mind that you won’t benefit from the discounted rate that comes with choosing the Full Package upfront.
It’s a free network of vetted local builders who we connect with homeowners once drawings are complete. Builders don’t pay fees; they simply recommend us in return.
We don’t take the full amount upfront. A deposit is paid once we’ve received your survey information, which allows us to programme your project into our schedule. The remaining balance is then split into clear, agreed milestones as we progress through your project — so you only pay as key stages are delivered.
On average, extensions range between £1,500 – £2,500 per m², but the exact cost will depend on factors like your chosen specification, location, and the complexity of the design.
Our detailed technical drawings make it easier for builders to provide accurate quotes. Beyond this, we can also work closely with our trusted network members to help optimise your design for buildability and budget — ensuring you get the most value from your extension without compromising on quality.
Permitted Development rights are rules that allow you to make certain changes to your home without needing full planning permission. They cover common projects like small rear extensions, loft conversions, or adding a porch.
There are limits though — things like the size, height, and position of the extension all matter. If your home is in a conservation area, national park, or is a listed building, your permitted development rights may be restricted or removed entirely.
We’ll always check at the start whether your extension qualifies as Permitted Development or if a planning application is required, so you know exactly where you stand before moving forward.
Planning Permission is about how your extension looks and fits into its surroundings. The council checks things like:
-
the size and height of your extension
-
its design and appearance
-
how it affects your neighbours and the street scene
Building Regulations are about how your extension is built. They cover things like:
-
structural stability (will it stand up?)
-
fire safety
-
energy efficiency and insulation
-
ventilation, drainage, and access
In many projects you’ll need both — Planning Permission for approval to build, and Building Regulations to make sure it’s built safely and to standard.
We’ve designed the process so you can carry out a measured survey yourself — no technical experience required.
As soon as you sign up with Plan my Extension, we’ll provide a clear, step-by-step guide showing you how to measure each room and take the key photos we need. You can use either a standard tape measure or a laser measure — whichever works best for you.
Once your measurements and photos are uploaded, our team will create accurate existing drawings to get your project underway.
Prefer to leave it to the pros? No problem — we’ll arrange for an approved builder from our network to carry out the survey for an additional fee.
Whichever route you choose, we’ll make sure you have everything needed to get started with confidence.
Plan my Extension is designed to make home design faster, simpler, and more affordable — without compromising on quality.
Unlike traditional practices, we operate fully online, which means no unnecessary site visits, meetings, or delays. You can manage your entire project from the comfort of your home, using our guided process and simple digital tools.
We also offer a unique self-survey model, allowing you to collect the necessary measurements yourself using our step-by-step instructions — saving time and reducing costs.
Plus, when your design is ready to build, we can connect you with our growing network of trusted local builders, helping you move from plans to construction with confidence.
In short, we’re here to make the home extension process smarter, more accessible, and tailored to modern homeowners.
Not always.
At Plan my Extension, we’ll help you find out whether your project qualifies as permitted development — a set of rights that allow certain types of home improvements without needing full planning permission.
If your plans don’t meet the permitted development criteria, you’ll need to apply for planning permission. But don’t worry — we can guide you through that process too.
Even if planning permission isn’t required, we strongly recommend applying for a Lawful Development Certificate. This provides official confirmation that your project is permitted — and we’re happy to handle the application for you.
Once you are happy to proceed, we’ll guide you through a simple, step-by-step process to kick things off.
We’ll ask for the following:
- Your name, contact details, and the address of the property
- Basic information about the property itself
- An overview of your goals — including your preferred style, estimated budget, and what you’re hoping to achieve
- Any timelines or deadlines you have in mind
- Survey information: floor plans, photos of the existing property, and any inspiration
If we need anything else before starting the design work, we’ll let you know right away.
