Data analysis reveals why planning applications fail in H&F. With 67% of the borough in conservation areas, heritage is the dominant factor. Learn the top 10 refusal reasons and expert strategies.
TL;DR - The Quick Answer
Hammersmith & Fulham has a 21% refusal rate for householder planning applications, higher than the London average. With 67% of the borough in conservation areas, the leading cause of refusal is harm to conservation area character, accounting for 42% of rejected applications. Other common reasons include harm to the original building character, loss of light to neighbours, and inappropriate dormer designs. Roof terraces face the steepest odds, with a 42% refusal rate borough-wide.
London Borough of Hammersmith & Fulham processes approximately 1,800 householder planning applications annually. With 67% of the borough designated as conservation areas, H&F has one of the most restrictive planning environments in London. Analysis from the H&F Planning Portal reveals clear patterns.
| Application Type | Applications/Year | Approval Rate | Refusal Rate |
|---|---|---|---|
| Single storey rear extension | ~680 | 84% | 16% |
| Basement extension | ~220 | 71% | 29% |
| Loft conversion (dormer) | ~340 | 76% | 24% |
| Side return infill | ~280 | 82% | 18% |
| Two storey rear extension | ~180 | 68% | 32% |
| Roof terrace | ~90 | 58% | 42% |
| Application Type | Approval Rate | Refusal Rate |
|---|---|---|
| Single storey rear extension | 84% | 16% |
| Basement extension | 71% | 29% |
| Loft conversion (dormer) | 76% | 24% |
| Side return infill | 82% | 18% |
| Two storey rear extension | 68% | 32% |
| Roof terrace | 58% | 42% |
Source: Mayfair Studio analysis of H&F Planning Portal data • Data as of 2025
H&F sees more basement applications than most London boroughs due to high land values and Victorian properties with limited above-ground expansion options. The 71% approval rate requires careful attention to structural surveys, party wall agreements, and construction management plans.
Analysis of H&F refusal notices reveals heritage dominates. Here are the 10 most common refusal reasons with expert strategies to avoid each:
The dominant refusal reason in H&F. With 67% of the borough in conservation areas, planners refuse extensions that "fail to preserve or enhance the character and appearance of the conservation area."
Extensions that harm the character of Victorian and Edwardian properties. H&F's housing stock is predominantly period buildings, and planners protect their architectural integrity.
Victorian terraces in H&F are closely spaced. Extensions causing "unacceptable loss of daylight and sunlight" to neighbours are consistently refused.
Oversized or poorly designed dormers that harm the roofscape. H&F is particularly strict on dormers visible from the street or conservation area views.
Roof terraces have a 42% refusal rate - the highest of any application type. Privacy, noise, and visual impact concerns drive refusals.
H&F adopted a basement SPD in 2013 following concerns about basement excavations. Applications without proper Construction Management Plans or structural assessments are refused.
Extensions with new windows overlooking neighbours' private areas. Particularly sensitive with two-storey extensions and dormer conversions.
Extensions that leave insufficient outdoor amenity space. H&F Local Plan requires adequate private outdoor space for family housing.
Using materials that don't match or complement the existing building and conservation area. H&F is strict on material quality.
Extensions that would harm protected trees or require removal of significant trees. Many H&F streets have protected trees.
Planning outcomes vary across H&F. Here's how different areas compare:
| Area | Designation | Approval Rate | Key Challenges |
|---|---|---|---|
| White City | None | 86% | Regeneration area, more flexibility |
| Shepherds Bush | Partial conservation | 78% | Mixed - depends on exact location |
| Hammersmith | Conservation + Article 4 | 74% | Victorian terraces, heritage strict |
| Fulham Broadway | Conservation | 76% | Period character protection |
| Parsons Green | Conservation + Article 4 | 71% | High heritage value, strict standards |
| Brackenbury | Conservation + Article 4 | 68% | Victorian village feel protected |
| Hurlingham | Conservation + Article 4 | 65% | Large houses, high expectations |
With 67% of H&F in conservation areas, design as if you're in one unless you're certain you're not. Traditional materials, sympathetic design, and heritage respect are expected everywhere.
H&F's high refusal rate makes pre-application advice essential. At £200-400, it's far cheaper than redesigning after refusal. Officers will tell you what's likely to be approved.
Choose an architect experienced in H&F conservation areas. Generic designs from architects unfamiliar with the borough's heritage expectations often fail.
H&F expects high-quality materials - timber windows, brick to match, natural slate. uPVC and concrete tiles are almost never acceptable in conservation areas.
If you need significant space, a basement may be more likely to succeed than a large rear extension. H&F accepts basements when properly planned and documented.
Hammersmith and Fulham has a 21% planning refusal rate - higher than the London average. With 67% of the borough in conservation areas, harm to conservation area character accounts for 42% of all rejections. Roof terraces face a 42% refusal rate. Basement extensions, by contrast, achieve 71% approval when properly documented.
H&F has a 79% approval rate for householder planning applications - lower than the London average of 85%. This reflects the borough's extensive conservation areas and heritage protections.
Generally no. H&F conservation area guidance requires timber or metal windows. uPVC is typically refused as harming the character of historic buildings. Some areas outside conservation areas may accept uPVC.
Standard householder applications take 8 weeks. However, H&F often requests extensions due to case complexity. Basement applications may take longer. Pre-application advice adds 4-6 weeks but is highly recommended.
Article 4 removes permitted development rights, meaning you need planning permission for changes that would normally be allowed without permission. H&F has Article 4 directions in 15 areas covering things like front boundary treatments, satellite dishes, and window replacements.
Yes, H&F permits basements with appropriate documentation. You'll need a Structural Method Statement, Construction Management Plan, and typically limit excavation to 50% of garden area. Single-storey basements are more likely to be approved than double basements.
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