Architectural Considerations for Rear Extensions: An In-Depth Look by Modernize Building

Planning to expand your home with a rear extension? Before diving in, take a look at the expert advice from Modernize Building to understand what such an extension entails.

Home extensions present an excellent solution for those seeking more space without the hassle of relocating. While they demand a substantial initial investment, they can yield significant returns upon selling your home. To provide a comprehensive perspective, three architects from Modernize Building offer invaluable insights on the extension process.

Extension Varieties

In UK cities, three primary extension types are commonly found: rear, side return, and wrapped extensions. Rear extensions stretch across the property's entire width from one garden wall to another. Side return extensions utilize the narrow space beside the rear projection of Victorian and Edwardian homes, incorporating the alleyway and expanding the closet wing. Wrapped extensions extend along the side and back of a property, available in single or double storey formats.

The most prevalent extension type is a single storey at the rear of a home. By expanding outwards, it's possible to merge separate areas and create a more open space with ample daylight, ultimately enhancing the property's value.

Permitted Development Rights

Many councils allow extensions under permitted development, negating the need for Planning Permission. Local councils and RIBA (Royal Institute of British Architects) provide downloadable documents outlining what is permissible under this designation.

Permitted development allows homeowners to extend a certain percentage of the volumetric space, including loft extensions. By submitting a pre-application with initial sketches and volume calculations, homeowners can determine whether their proposed extension falls within the permitted development. However, understanding the complex criteria is challenging, so professional assistance is recommended to ensure compliance and avoid planning consultation.

Planning Permission

If permitted development doesn't cover your property, Planning Permission is required. This process involves submitting scale drawings of plans, elevations, sections, and the property's relationship to surrounding buildings. While it's possible to apply for Planning Permission independently, most people enlist a professional's help for expert advice and guidance.

Conservation Areas

For properties in conservation areas, permitted development isn't allowed, and Planning Permission becomes more stringent. Your local planning authority can help you determine if your property falls within a conservation area.

Design and Architect Assistance

Architects can provide design and technical drawing assistance for your extension. After discussing initial fees, they'll create concept design sketches, then develop detailed design drawings and specifications once you approve the concept. These documents can be used for Planning Permission if necessary.

Architects can offer a range of services, from initial design sketches to complete project management. Engaging an architect helps avoid pitfalls and ensures greater control over the final result and cost.

Building Regulations

All extensions must adhere to strict Building Regulations, separate from Planning Permission. Structural engineers and inspectors ensure the final plans are technically sound, structurally safe, and properly drained. Energy efficiency requirements are particularly strict, making it challenging to include highly glazed extensions without resorting to expensive triple-glazed units.

Informing Neighbours

Although not legally required for permitted development, informing neighbours is a considerate gesture. For projects requiring Planning Permission, the planning office will notify your neighbours. Additionally, a party wall consent process is typically necessary, potentially involving a party wall surveyor and added costs.

Tendering Your Project

The tender contains information for builders to obtain specifications from suppliers, along with overhead and profit calculations. Modernize Building strongly recommends requesting bids from at least four builders to compare costs.

Contractor-Led Projects

Hiring contractors and managing the project without an architect is possible, but pitfalls may arise if you're inexperienced. Smaller projects may not warrant architect involvement due to the proportionally higher fees.

Building Materials

Material options for your extension range from glass, timber cladding, and brick to more exotic choices like zinc and copper cladding. Two primary approaches govern material selection: maintaining consistency with the existing structure or creating a striking contrast. Aesthetic preferences, cost, and environmental considerations will influence your decision.

Coping with Disruption

Expect considerable disruption during the extension process, including noise, dust, and a sense of intrusion. Nevertheless, the outcome typically justifies the inconvenience. A standard single storey extension may take 2-3 months to complete, but the duration can vary from as little as one month to over six months, depending on the project.

Prudent Planning

Exercising caution with extensions is essential, as spending excessively doesn't guarantee a return on investment. Value added depends on the location, with premium spaces yielding higher returns. Consulting a local estate agent for a rough valuation and factoring that into your budget is advisable. Assessing your property concerning its location is crucial, as there may be a ceiling value that limits potential returns.

In conclusion, planning a rear extension requires careful consideration of various factors, including extension type, permitted development rights, Planning Permission, conservation areas, design, Building Regulations, and material selection. By following the expert advice from Modernize Building and taking a prudent approach, you can successfully extend your living space while enhancing your property's value.