
Single-storey, double-storey, rear and side extension drawings for Olney homes — measured to Milton Keynes City Council's design guidance, delivered in days and revised free until your decision, with a free approval-odds check before you commit.
Milton Keynes City Council granted 92% of the householder planning decisions it made in its latest published year — 1.7000000000000028 points above the 90.3% England-wide householder average. The Olney conservation area's Article 4 direction removes PD rights on all extensions, alterations, porches and exterior painting, so even minor works need consent, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837) and Victorian (1837–1901) housing stock sets the design brief on most streets.
The permitted-development ceilings are fixed: 40m³ of new roof volume for a terraced loft and 50m³ for a semi or detached house under Class B, plus a 3m single-storey rear extension on a terrace or 4m on a detached house under Class A. Olney carries at least one Article 4 direction, and conservation areas including Olney, Emberton and Clifton Reynes remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Olney is determined against an 8-week statutory target.
Olney (a Georgian market town on the Great Ouse, under an Article 4 conservation area), Emberton (a limestone village and conservation area south of the town), Clifton Reynes (a small riverside village and conservation area across the Ouse), Weston Underwood (a historic estate village and conservation area to the west), Lavendon (a stone-built village and conservation area on the road to Bedford) and Warrington (an outlying hamlet on the Ouse near Olney) — these are the Olney pockets our drawings cover most. Heritage designations here include Olney, Emberton, Clifton Reynes, Weston Underwood and Lavendon. Milton Keynes City Council weighs each proposal against Plan:MK (the Milton Keynes Local Plan 2019), where Olney sits in the rural north of the borough, well outside the New Town grid, with a listed Georgian core around the Market Place and church. On roofs the borough is pitched clay-tile, thatch and stone-slate roofs on the historic core and gabled roofs on the modern estates, over Georgian and Victorian market-town housing around the Market Place, limestone and brick cottages in the surrounding villages and later 20th-century estate housing on the town's edges.
Olney homes come in a handful of recurring shapes, and each one points to a different extension. The borough is built largely from Georgian and Victorian market-town housing around the Market Place, limestone and brick cottages in the surrounding villages and later 20th-century estate housing on the town's edges, so a Victorian terrace usually wants a rear or side-return infill, while an interwar semi has room for a wider single-storey wrap or a two-storey side addition. Milton Keynes City Council judges every one of them against Plan:MK (the Milton Keynes Local Plan 2019), weighing footprint, height and the impact on the house next door before it looks at the elevations.
That is why the drawings decide the outcome. We set the extension depth against the permitted-development limits precisely, keep the eaves and ridge within the allowances, and plot the 45-degree daylight lines to the neighbours' windows so the case officer can see the amenity test is passed. The Olney conservation area's Article 4 direction removes PD rights on all extensions, alterations, porches and exterior painting, so even minor works need consent, so we design around it from the first sketch rather than discover it at validation.
Olney also protects whole streets — Olney, Emberton, Clifton Reynes, Weston Underwood and Lavendon among them. The Olney conservation area carries an Article 4 direction: all dwellinghouses lose permitted-development rights for any extensions or alterations, porches, and the painting of exterior walls — introduced to safeguard the Georgian market town's character. On designated land the larger-home extension route and most side extensions stop being permitted development, so we confirm your address against those layers before drawing a line.

Plenty of Olney extensions are permitted development and need no planning application — a single-storey rear extension within the depth and height limits is the common case. You will normally need to apply to Milton Keynes City Council if any of these apply:
We draw the footprint, the ridge and eaves heights and the neighbours' daylight on the page — the relationships Milton Keynes City Council's officers weigh first — and submit a validation-complete pack, whether that is a lawful development certificate, a prior-approval notification or a full householder application.
Below is Milton Keynes City Council's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Milton Keynes approves the large majority of householder applications, but Olney's Article 4 direction and Georgian conservation-area character make it the borough's most tightly controlled market town. A complete, policy-literate extension pack anticipates those pressure points before submission, which is why professionally drawn applications are decided faster and refused less often than DIY ones.
Source: MHCLG planning application statistics (householder decisions, England, 1 April 2025 - 31 March 2026). Compare every borough on our London approval-rate league table.
Tell us about your project and get a fixed, no-obligation quote back within one working day. If you don't need planning permission at all, we'll tell you that too — for free.
Across Olney, Emberton and Clifton Reynes, the extension that lands most often is the single-storey rear addition — a glazed kitchen-diner across the back of the house, kept within the permitted-development depth or taken to a full application where the ground floor wants more. On the borough's georgian and victorian market-town housing around the market place, a side-return infill frequently pairs with it to square off the plan; on wider later 20th-century estate housing on the town's edges, a two-storey side or rear extension can add a bedroom above without swallowing the garden.
Olney sits in the rural north of the borough, well outside the New Town grid, with a listed Georgian core around the Market Place and church. We size the extension to the amenity and daylight tests, match the roof and materials to the host house, and keep enough garden to satisfy Milton Keynes City Council's space standards — so the scheme answers the borough's questions before an objection can raise them. Where permitted-development rights are used up or removed, we prepare the householder application to the council's extension design guidance instead.

We draw extensions on every street in the borough. A few of the neighbourhoods where Olney projects come up most often:
Extension drawings for Olney's a Georgian market town on the Great Ouse, under an Article 4 conservation area — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
Extension drawings for Emberton's a limestone village and conservation area south of the town — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
Extension drawings for Clifton Reynes's a small riverside village and conservation area across the Ouse — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
Extension drawings for Weston Underwood's a historic estate village and conservation area to the west — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
Extension drawings for Lavendon's a stone-built village and conservation area on the road to Bedford — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
Extension drawings for Warrington's an outlying hamlet on the Ouse near Olney — footprint-checked, daylight-tested and drawn to Milton Keynes City Council's guidance.
The right extension in Olney depends on your house type and how much garden you can give up. This is how the main options compare on planning route and what they add.
| Extension type | Permitted development? | What it adds | What Milton Keynes City Council checks |
|---|---|---|---|
| Single-storey rear | Often, within 3m/4m depth (6m/8m via prior approval) | Bigger kitchen-diner across the back | Depth, height, neighbour daylight (45°) |
| Side-return infill | Sometimes, if within width and height limits | Squares off an L-shaped ground floor | Width vs the original house, glazing to boundary |
| Two-storey rear/side | No — full application | Extra bedroom or bathroom above | Bulk, overlooking, 7m rear-boundary gap |
| Wraparound (rear + side) | No — full application | Whole-width open-plan ground floor | Combined footprint and garden retained |
Route depends on your street — conservation areas such as Olney and Emberton and Article 4 directions can remove permitted-development rights.
A fixed process built around how Milton Keynes City Council validates and decides householder extension applications — most drawings are submission-ready within seven days of survey.
Tell us your Olney postcode and house type. We confirm your conservation and Article 4 status, how much permitted-development depth you have left, and score your odds against live Milton Keynes City Council decisions.
We measure the existing footprint, floor and eaves levels, boundary distances and the neighbours' window positions — the numbers the depth limits and daylight tests depend on.
Chartered designers develop the single-storey, two-storey or side extension to your brief, drawn inside the permitted-development limits or to Milton Keynes City Council's extension design guidance.
We submit the certificate, prior-approval notice or application, manage validation and case-officer queries, and revise the drawings free until Milton Keynes City Council issues its decision.
Not always. A single-storey rear extension up to 3 metres deep on a terrace or semi, or 4 metres on a detached house, and no higher than 4 metres, is usually permitted development. In Olney you will need to apply to Milton Keynes City Council for two-storey extensions, side extensions wider than half the house, anything forward of the front wall, deeper rear extensions under the larger-home prior-approval route, and any extension in a conservation area such as Olney and Emberton.
Standard permitted development allows 3 metres on a terraced or semi-detached house and 4 metres on a detached one. The larger-home extension scheme can double that to 6 or 8 metres, but it needs a prior-approval notification to Milton Keynes City Council and a neighbour-consultation period, and it does not apply on designated land such as Olney's conservation areas. We confirm which route your property qualifies for before drawing.
Two-storey and double-storey extensions almost always need a full householder application to Milton Keynes City Council, because they fall outside permitted development on most homes. The council looks closely at bulk, overlooking of neighbours and the 7-metre gap a two-storey rear extension must keep from the rear boundary. We design to those tests and show the daylight and privacy angles on the drawings. This applies to your Olney address specifically.
A householder planning application in Olney runs to a statutory eight-week target, a larger-home prior-approval notification to around six weeks including the neighbour-consultation period, and a lawful development certificate to eight weeks. Incomplete submissions stall at validation, so we submit a complete pack and manage officer queries to keep the decision on schedule. Milton Keynes City Council is the decision-maker.
Yes — planning permission and building regulations are separate consents, and almost every extension needs both. Planning governs whether you can build it; building control governs how it is built, covering structure, insulation, drainage and fire safety. We prepare the building-regulations drawings alongside the planning set so Milton Keynes City Council's building control or a registered building control approver can sign the work off. This applies to your Olney address specifically.
Every house and brief is different, so we price each Olney extension individually and send a fixed, no-obligation quote back within one working day. It covers the full drawing pack with free revisions until Milton Keynes City Council approves, and we tell you upfront whether your extension qualifies as permitted development. Call 020 7864 7245 to get started.
Answer five quick questions and get a free planning score for your exact address — instantly. Then, if you want the full picture, unlock the detailed analysis: your council's live approval rates, local precedents, constraints on your street and a step-by-step route to permission.
Same fixed quotes, same fast drawings — wherever your project is.