Because every number that matters is a measurement. How close the extension sits to your boundary, the ridge and eaves heights, the floor area, what has already been built — all of it decides your planning position, your council fee and what your builder charges. None of it can be established over the phone.
📋 Book the £60 site visit ↓ What he measures, and whyPlenty of firms will give you a figure on a call. It costs them nothing, and it is worth exactly that — because at the point they gave it, they did not know how far your extension sits from the boundary, how high your existing ridge is, or whether a previous owner already used up your Permitted Development allowance.
That matters more than it sounds. Getting the planning position wrong is a £734 swing in Wales, or £697 in Chester and Wirral — the council fee plus the Planning Portal charge. A homeowner told on the phone that they probably would not need permission, who then finds out they do, has been given the worst possible start: a number they trusted, corrected later.
Mike will not do that to you. He measures first, then tells you. That is the whole reason the site visit exists, and the whole reason it comes before a fee proposal rather than after.
None of these are formalities. Each one changes either what you are allowed to build, what you will pay the council, or what your builder will quote.
How close the extension sits to each boundary is one of the main tests for Permitted Development, and it drives the fire and window rules in the building regulations. It has to be measured, not estimated from a fence line you remember.
A roof cannot go above the highest part of the existing one and stay Permitted Development, and eaves heights are limited near a boundary. Heights are the single commonest reason a project people assumed was permitted turns out not to be.
Depth of projection and added volume are hard limits, and the loft allowance — 40m³ terraced, 50m³ detached and semi — is cumulative. Mike has to know the actual figures to tell you where you sit against them.
An extension has to sit properly against what is already there. Proportion, roof pitch, window lines and materials are what a planning officer judges, and getting them right first time is the difference between an approval and a refusal.
Earlier extensions and conversions count against your allowance — including work done by a previous owner decades ago that you know nothing about. Mike checks the property's planning history as well as measuring it.
What is holding the roof up, how the floors are built, where the drains run. This is what decides whether your idea is straightforward or expensive, and it is what your builder prices from.
| What Mike measures | What it decides |
|---|---|
| Distance to boundaries | Permitted Development or a planning application · fire and window requirements |
| Ridge and eaves heights | Permitted Development or not · whether the design needs rethinking |
| Floor area, depth and volume | Permitted Development limits · building control charge · your builder's price |
| Scale and proportion | Whether a planning officer is likely to approve it |
| Previous extensions | How much allowance you have left, if any |
| Existing structure and drainage | What is buildable · steel sizing · the real cost of the job |
Every one of those feeds the drawings. Drawings built on guesses get corrected by the council, or worse, by the builder halfway through — and that is when a project stops being a fixed price.
He surveys your home himself — no juniors, no outsourcing, no subcontracted measurer. Twenty-five years of doing this on houses like yours.
Whether your project is Permitted Development or needs an application — checked against the measurements and your property's planning history, not guessed.
Including when the answer is that your idea will not achieve what you want, or that a different approach would get you more for the same money.
Sent afterwards, in writing, before any work begins. The number you agree is the number you pay.
And the £60 comes off. Commission the work and the full £60 is deducted from your agreed fee — so for anyone who goes ahead, the visit costs nothing. It exists so Mike is not giving away measured surveys to people who are only collecting prices.
Mike's fee plus the council fees for planning and building control — the full professional stage, before a builder is involved. Two taps for a figure — no obligation.
Mike's fee covers the complete professional package:
Why the range? Every home is different. The lower end covers a straightforward project — a simple survey, standard drawings, no planning application needed. The higher end covers larger or more complex work — a full planning application, more detailed drawings, or structural design to coordinate.
Before any work begins, Mike gives you a detailed written fee proposal — so you know exactly what you're paying and what it covers. The number you agree is the number you pay.
The visit. Mike comes to your home, assesses your space and your plans, tells you whether you need planning permission, and gives you honest advice on what's possible and what it's likely to cost. The visit fee is £60.
Commission the work and it's free. If you go ahead, the full £60 is deducted from your agreed fee — so the visit effectively costs you nothing.
Work beyond the agreed scope. Anything over and above the written fee proposal — amendments after approval, planning appeals, project management — is charged separately at £60 per hour, always agreed with you first.
What it is. The fee your council charges to process a householder planning application — their planners assess your proposed extension against local and national planning policy before granting permission.
Why it's needed. Larger extensions, or ones outside the Permitted Development rules, legally need planning permission before work starts. Many smaller extensions don't need it at all — Mike will tell you which side you're on at your site visit.
How you pay. Paid directly to your council when the application is submitted — it never passes through Mike. The fee is set nationally: £585 in Wales (Flintshire, Denbighshire and Wrexham) and £548 in Cheshire West & Chester. Mike prepares, submits and handles the whole application as part of his fee. Applications go in online via the Planning Portal, which adds a £149 service charge for a householder application on top of the council fee.
What it is. The Planning Portal is the official national website where planning applications are submitted online to councils across England and Wales — it's how applications reach your council's planning department.
Why the charge. The Planning Portal is the official route applications take to your council, and it charges a service fee on any application whose council fee is over £100. Since 2026 that fee is banded by application type: Band 1 is £99 inc VAT and Band 2 is £149 inc VAT. A householder application to enlarge, improve or alter an existing dwelling — which is what an extension, loft or garage conversion is — sits in Band 2, so £149. It is charged per application submitted, so a project that goes to outline permission first and reserved matters afterwards pays it twice. You can check any application type against the Planning Portal’s published bands.
How you pay. Paid online at the point of submission, together with the council's planning fee. Mike prepares and submits the application through the Portal on your behalf — this charge just doesn't apply at all if your project is Permitted Development, because there's no application to submit.
What it is. Completely separate from planning — building control checks that the construction itself meets the Building Regulations: structure, insulation, fire safety, drainage. An inspector approves the technical drawings and visits the build at key stages.
Why it's needed. It's a legal requirement for extensions and conversions, even when no planning permission is needed. At the end you receive a completion certificate — which you'll need when you come to sell the house.
How you pay. Paid directly to the council's building control team or a private approved inspector — typically a plan charge when the drawings go in and an inspection charge when work starts. Charges vary by council and project size, which is why this line is approximate: Mike obtains an exact quote for you once the design is finalised. Not part of Mike's fee.
Design and approvals only. This is what it costs to get your project drawn and approved — it does not include your builder’s costs for the actual building work.
If your project turns out to be Permitted Development, up to £734 of this comes off — Mike checks for free at your site visit.
Read more about extension plans →
Already built it without approval? Regularisation →
Guide figures only. The £60 site visit is not added to the total — it comes off Mike's fee when you commission the work. Council fees correct at July 2026; building control charges vary by council and project — full details in the FAQs. Mike confirms everything in a written fee proposal before any work begins.
Or have Mike email this estimate to you — no obligation.
✅ Sent — Mike will email your estimate today. No obligation.
Couldn't send just now — call Mike on 07703 786 460 or email [email protected].
Every planning application Deeside Architectural Design submits goes onto the council's public register — under the practice name, with the decision attached, permanently. It's free to search and it isn't curated by us. What the register cannot show you is the other half of the work: the projects that qualified as Permitted Development, needed no application at all, and saved the client the council fee. Those leave no public trace. So the number below is the part you can check — not the whole of it. Before you decide whether the fee above is worth paying, go and read it.
Submitted to Flintshire County Council under Deeside Architectural Design since 2010 — every one searchable, with its decision attached.
Many projects qualify as Permitted Development, need no application, and never reach the register. The 165 is the work that required permission — not the count of jobs done.
Deeside Architectural Design Limited, incorporated January 2010, and 25 years of drawings behind it. Companies House no. 07128221.
Open Flintshire's planning register, put Deeside Architectural in the Agent field, and read every decision — including the ones that didn't go our way.
Search Flintshire's planning register →
Figures taken from Flintshire County Council's public planning register, August 2026.
No. Photographs give no dimensions, and a description cannot confirm boundary distances or heights to the accuracy the drawings need. He also needs to see the existing structure — what holds the roof up, how the floors are built, where the drains run — because that decides what is possible and what a builder will charge.
They are quoting without the measurements, which means they are guessing — and the correction comes later, usually when it is expensive. Mike would rather charge £60, measure properly, and give you a figure that holds. If you go ahead the £60 comes off, so it costs you nothing.
Use the estimator on this page — three project types, your council, and it gives you a realistic range for the design and approvals stage with no obligation and nothing to fill in. You can have it emailed to you if you would rather think about it.
Then you found that out for £60, rather than after paying a council fee and commissioning drawings. He will tell you at the visit if he thinks an application is likely to be refused, or if what you have in mind will not get you what you want.
Usually under an hour. Mike measures, looks at the existing structure, talks through what you are hoping to do, and answers your questions. The written fee proposal follows afterwards.
Two taps on the estimator gives you a realistic figure. When you're ready, the £60 site visit comes off your fee if you go ahead.
⚡ Instant estimate Book the site visit