Dormer, hip-to-gable and mansard loft conversion drawings for Dacorum homes — prepared to Dacorum Borough Council's design guidance, delivered in days and revised free until your decision lands, with a free approval-odds score first.
Dacorum Borough Council granted 87% of the householder planning decisions it made in its latest published year — level with the 87% England-wide householder average. Extensive Metropolitan Green Belt covers the rural borough, concentrating growth on the three main towns and allocated sites, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837), Victorian (1837–1901), interwar (1918–1939) and postwar (1945–1970) 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. Dacorum carries at least one Article 4 direction, and conservation areas including Hemel Hempstead Old Town, Berkhamsted and Tring remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Dacorum is determined against an 8-week statutory target.
Hemel Hempstead (a postwar New Town of planned neighbourhoods around the Marlowes centre), Berkhamsted (a historic canal-side market town in a Chilterns setting), Tring (a historic market town at the Chilterns gap), Kings Langley (a historic commuter village with a conservation-area core), Aldbury (a model rural conservation village below the Chilterns) and Bovingdon (a rural Green Belt village) — these are the Dacorum pockets our drawings cover most. Heritage designations here include Hemel Hempstead Old Town, Berkhamsted, Tring, Aldbury, Kings Langley and Bovingdon. Dacorum Borough Council weighs each proposal against the Dacorum Core Strategy 2006–2031 (adopted September 2013), where the Chilterns National Landscape (AONB) covers and adjoins Berkhamsted and Tring, adding landscape-protection constraints on design and siting. Converted and purpose-built flats appear across Hemel Hempstead and the town centres, and none of them hold householder permitted-development rights.. On roofs the borough is pitched tiled roofs on the postwar New Town housing and steep tiled and gabled roofs on the historic market-town and village cores, over postwar New Town planned neighbourhoods across Hemel Hempstead around the Marlowes centre, medieval, Georgian and Victorian market-town cores at Berkhamsted and Tring, interwar and Victorian stock and vernacular cottages in the surrounding villages and larger detached housing on the Chilterns fringe.
Dacorum's roofs set the brief. The borough is built largely from postwar New Town planned neighbourhoods across Hemel Hempstead around the Marlowes centre, medieval, Georgian and Victorian market-town cores at Berkhamsted and Tring, interwar and Victorian stock and vernacular cottages in the surrounding villages and larger detached housing on the Chilterns fringe, and its lofts sit under pitched tiled roofs on the postwar New Town housing and steep tiled and gabled roofs on the historic market-town and village cores — the geometry that decides whether a rear dormer, a hip-to-gable or a mansard gives you the headroom you want. Dacorum Borough Council assesses loft proposals against the Dacorum Core Strategy 2006–2031 (adopted September 2013), and its case officers read each roof against the pair next door and the wider street before they read the plans.
That makes drawing quality decisive. We measure ridge and eaves heights, roof pitch and the existing stair, calculate the added volume against the permitted-development limits exactly, and show the workings on the drawings so Dacorum Borough Council can verify them. Extensive Metropolitan Green Belt covers the rural borough, concentrating growth on the three main towns and allocated sites, so we resolve it on the page rather than leave it for the case officer to raise.
Dacorum also carries protected streets — Hemel Hempstead Old Town, Berkhamsted, Tring, Aldbury, Kings Langley and Bovingdon among them. Dacorum's Article 4 directions, confirmed in November 2022, cover employment and town-centre areas and retain the requirement for planning permission to convert identified properties to residential use, and the borough's twenty-five conservation areas add further character controls. We check your address against those designations before a line is drawn.
Many Dacorum loft conversions proceed without planning permission — a rear dormer within the permitted-development volume limits (40 cubic metres on a terrace, 50 on a semi or detached house) is usually lawful. You will normally need a full application to Dacorum Borough Council if any of these apply:
We draw the roof line, the ridge height and the neighbour's daylight on the page — the relationships Dacorum Borough Council's officers check first — and submit a validation-complete pack, whether that is a lawful development certificate or a full householder application.
Below is Dacorum Borough Council's real householder decision record, pulled from official planning statistics and updated as new data lands. Dacorum grants a fair share of householder applications, with green-belt containment, the Chilterns AONB and its many conservation areas the recurring constraints on larger schemes. Professionally prepared loft drawings anticipate those pressure points before submission, which is why complete, policy-literate packs are decided faster and refused less often than DIY applications.
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 Hemel Hempstead, Berkhamsted and Tring, the recurring loft is the rear dormer — a box across the back roof slope that turns a cramped attic into a full-height double bedroom and en-suite. On pitched tiled roofs on the postwar New Town housing, that is usually the most efficient use of the roof; where the stock is steep tiled and gabled roofs on the historic market-town and village cores, a hip-to-gable followed by a rear dormer unlocks far more space, though it needs a full application.
The Chilterns National Landscape (AONB) covers and adjoins Berkhamsted and Tring, adding landscape-protection constraints on design and siting. We draw the dormer inside the volume allowance, keep the flat-roof build-up below the ridge, and set the face back from the eaves as the rules require — so the pack answers Dacorum Borough Council's questions before they are asked. Where permitted-development rights are exhausted or removed, we prepare a householder application composed to the borough's roof-alteration guidance instead.
We draw loft conversions on every street in the borough. A few of the neighbourhoods where Dacorum roofs come up most often:
Loft conversion drawings for Hemel Hempstead's a postwar New Town of planned neighbourhoods around the Marlowes centre — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
Loft conversion drawings for Berkhamsted's a historic canal-side market town in a Chilterns setting — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
Loft conversion drawings for Tring's a historic market town at the Chilterns gap — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
Loft conversion drawings for Kings Langley's a historic commuter village with a conservation-area core — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
Loft conversion drawings for Aldbury's a model rural conservation village below the Chilterns — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
Loft conversion drawings for Bovingdon's a rural Green Belt village — measured, volume-checked and drawn to Dacorum Borough Council's guidance.
The right loft in Dacorum depends on your roof. This is how the main types compare on planning route and the space they add.
| Loft type | Permitted development? | Space & headroom | What Dacorum Borough Council checks |
|---|---|---|---|
| Rear dormer | Usually yes, within volume limits | Full-height double room at the back | Volume, set-back from eaves, ridge height |
| Hip-to-gable | No — full application | Extends the whole side of the roof | Roof bulk and the symmetry of the pair |
| Mansard | No — full application | Maximum floor area across the roof | Street character, especially in conservation areas |
| Rooflights only | Usually yes (Class C) | Light and headroom, no extra footprint | Whether rooflights sit within the existing slope |
Route depends on your street — conservation areas such as Hemel Hempstead Old Town and Berkhamsted and Article 4 directions can remove permitted-development rights.
A fixed process built around how Dacorum Borough Council validates and decides householder loft applications — most drawings are submission-ready within seven days of survey.
Tell us your Dacorum postcode and roof type. We confirm your conservation and Article 4 status, how much permitted-development volume you have left, and score your odds against live Dacorum Borough Council decisions.
We measure ridge and eaves heights, roof pitch, joist levels and the existing stair — the numbers the volume calculation and head heights depend on.
Chartered designers develop the dormer, hip-to-gable or mansard to your brief, drawn inside the Class B limits or to Dacorum Borough Council's roof-alteration guidance.
We submit the certificate or application, manage validation and case-officer queries, and revise the drawings free until Dacorum Borough Council issues its decision.
Often not. A rear dormer within 40 cubic metres on a terrace, or 50 on a semi-detached or detached house, set back from the eaves and no higher than the ridge, is usually permitted development. In Dacorum the main exceptions are hip-to-gable conversions, dormers visible from the highway, and homes in conservation areas such as Hemel Hempstead Old Town and Berkhamsted or on streets with an Article 4 direction. Dacorum Borough Council is the decision-maker.
Generally no. In conservation areas including Hemel Hempstead Old Town and Berkhamsted, Class B permitted-development rights for lofts are removed, so a rear dormer that would be lawful elsewhere needs a full application to Dacorum Borough Council. Dacorum's Article 4 directions, confirmed in November 2022, cover employment and town-centre areas and retain the requirement for planning permission to convert identified properties to residential use, and the borough's twenty-five conservation areas add further character controls. We check your exact address before drawing.
On pitched tiled roofs on the postwar New Town housing, common across Dacorum, a rear dormer is usually the most efficient conversion and often permitted development. Where the roof is steep tiled and gabled roofs on the historic market-town and village cores, a hip-to-gable followed by a rear dormer gains far more usable space but needs planning permission. Our survey confirms which your roof supports before we draw. Dacorum Borough Council is the decision-maker.
A householder planning application in Dacorum runs to a statutory eight-week target, and a lawful development certificate to eight weeks as well, though validation can add time if the pack is incomplete. We submit validation-complete drawings and manage case-officer queries to keep the decision on track. Dacorum Borough Council is the decision-maker.
If your dormer is permitted development, a lawful development certificate from Dacorum Borough Council is council-stamped proof of that — worth having, because every buyer's solicitor will ask for it when you sell. We prepare and submit the certificate application with the same drawing pack.
Every roof is different, so we quote each Dacorum project individually — a fixed, no-obligation price back within one working day. The quote covers the full drawing pack with free revisions until Dacorum Borough Council approves, and we tell you upfront whether your loft qualifies as permitted development. Call 020 7864 7245 to start.
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.