Frequently asked questions

Yes – we provide a complete architectural service from initial concept design through to construction and completion. This includes measured surveys, concept development, planning applications, technical detailing, tendering, and on-site contract administration. During construction, we carry out site visits, respond to contractor queries, and help ensure the design is delivered as intended.

Permitted development rights typically apply to certain residential works such as rear extensions, loft conversions, and internal alterations, subject to limits on size, height, and location. However, these rights can be restricted for listed buildings, conservation areas, or properties with existing planning conditions. We assess your property at an early stage to confirm whether your project qualifies or requires a full planning application.

Yes – we can work with your chosen builder and integrate them into the project at the appropriate stage. If needed, we can also assist in identifying and shortlisting suitable contractors through a structured tendering process, helping you compare quotations and select a contractor based on quality, cost, and experience.

For most residential projects, planning decisions are typically issued within 8 weeks from submission. More complex schemes, or those requiring additional consultation, may take longer. We manage the submission process and liaise with the local authority throughout to help minimise delays and respond to any queries raised during assessment.

Yes – we regularly take on projects that are already underway or previously designed. We review existing drawings, identify opportunities for improvement, and refine the design to better align with planning requirements, construction feasibility, and your overall brief.

Yes – we have experience working with listed buildings and properties within conservation areas, where additional planning and heritage constraints apply. These projects often require listed building consent alongside planning permission, and a careful design approach to preserve the building’s character while enabling modern use.

A typical planning application includes existing and proposed plans, elevations, and sections, along with site location and block plans. Depending on the project, additional documents such as a design and access statement may be required. We prepare and coordinate all drawings and supporting information to ensure a clear and complete submission.

Planning permission relates to the design, appearance, and impact of a development on its surroundings. Building regulations focus on how the project is constructed, covering structural integrity, fire safety, insulation, drainage, and other technical standards. Both are usually required, and we guide you through each stage.

Yes – early-stage planning advice is a key part of our process. We assess your property, local planning policies, and site-specific constraints before design begins. This helps define what is realistically achievable and reduces the risk of delays, redesign, or refusal later in the project.

We design a wide range of house extensions including rear extensions, side return extensions, wrap-around extensions, and double-storey additions. Each project is tailored to the property type and client brief, with a focus on improving layout, natural light, and connection to outdoor space.

The design stage typically takes between 2 to 6 weeks, depending on the complexity of the project and the level of design development required. This includes initial concepts, revisions, and preparing drawings for planning submission.

In many cases, yes – particularly for smaller extensions. However, this depends on the scale of the works and how much of the existing house is affected. For larger or more complex projects, temporary relocation may be recommended to ensure safety and efficiency during construction.

Yes – we regularly work on terraced and semi-detached properties across London. These projects often involve constraints such as limited space, neighbouring properties, and party wall considerations, all of which we address during the design and planning stages.

Some extensions can be carried out under permitted development rights, depending on size, height, and location. However, many projects require planning permission. We assess your property early and advise on the most appropriate route before progressing the design.

Costs vary depending on the size, specification, and complexity of the project. Factors such as structural work, glazing, and interior finishes will influence the overall budget. We help define a realistic scope early on and can support cost control through the design and tender stages.

A well-designed extension can significantly increase both the usability and value of a property, particularly in London where additional space is highly sought after. The impact depends on the quality of design, layout improvements, and how well the extension integrates with the existing house.

Whether your loft falls under permitted development or householder development, we will guide you through the appropriate application process.

Design and planning typically take 2-3 months. Construction lasts around 8-12 weeks, depending on the complexity, contractor and weather conditions. We help coordinate the timeline to fit around your family and builder availability.

Yes – many of our clients create new master suites with bespoke storage and bathrooms. We help configure the space to meet your needs.

A dormer loft conversion involves extending vertically from the existing roof slope to create additional headroom and usable floor space. It is one of the most common types of loft conversions in London, allowing for larger rooms and improved natural light.

Common types include dormer, hip-to-gable, mansard, and rooflight (Velux) conversions. The appropriate option depends on your roof structure, property type, and planning constraints.

An L-shaped loft conversion typically combines two dormer extensions – one on the main roof and one on the rear projection. This configuration is often used in Victorian and Edwardian properties to maximise floor area and create multiple rooms.

A minimum ceiling height of around 2.1m is generally recommended to allow for sufficient headroom.

Many loft conversions fall under permitted development rights, but this depends on factors such as volume increase, roof alterations, and property location. We assess your property early to determine the most appropriate planning route.

Planning permission may be required depending on the scale of the excavation, external alterations, and local borough policies. Some smaller internal works may not require permission, but basements in London are often subject to stricter controls. We assess this at an early stage and advise on the appropriate route.

Basement construction typically takes between 4 to 8 months, depending on complexity, structural requirements, and site conditions. Larger or multi-level basements may take longer due to excavation and structural sequencing.

Yes – most basement projects will require party wall agreements, particularly in terraced or semi-detached properties. We coordinate with party wall surveyors and ensure the correct procedures are followed before construction begins.

We incorporate specialist waterproofing systems and drainage strategies as part of the technical design. This typically involves collaboration with structural engineers and waterproofing specialists to ensure long-term protection against water ingress.

Yes – basements are commonly added to terraced properties in London. These projects require careful structural design, coordination with neighbouring properties, and consideration of access, excavation, and construction logistics.

Basements can accommodate a wide range of spaces including living areas, kitchens, home cinemas, gyms, guest bedrooms, and utility rooms. The layout is tailored to your needs, with a focus on natural light, ventilation, and functionality.

Natural light can be introduced through lightwells, rooflights, glazed doors, and internal courtyards where feasible. These design strategies help create bright, usable spaces that feel connected to the rest of the home.

Yes – but carefully. While original features must be preserved, smart and sensitive design allows for modern living upgrades.

When renovating a listed building, listed building consent is often required. There will also be occasions where planning permission and listed building consent are required. We handle this process for you, navigating your selected proposals through the relevant planning, conservation and building regulation requirements.

Yes. Any alterations, renovations, or extensions to a listed building require Listed Building Consent in addition to standard planning permissions. At Armstrong Simmonds Architects, we guide you through this process, preparing the necessary applications and ensuring your project complies with heritage regulations while achieving your design goals.

Listed buildings in the UK are classified into three grades. Grade I buildings are of exceptional interest, Grade II* are particularly important buildings of more than special interest, and Grade II are of special interest. The level of protection and scrutiny increases with each grade.

Listed Building Consent is required for any works that affect the character or historic significance of the property. This can include extensions, alterations, and sometimes even minor changes to materials or details. We advise on this early and manage the application process where required.

Yes – internal alterations can require Listed Building Consent if they affect the character of the building. This may include changes to layouts, removal of walls, or alterations to original features such as fireplaces, mouldings, or staircases.

Original features are typically protected and should be retained wherever possible. In some cases, sensitive alterations may be approved if they are justified and carefully designed. We develop proposals that balance modern requirements with heritage considerations.

Yes – modern extensions or interventions can be permitted if they are designed sensitively and respect the historic context of the building. This often involves a considered contrast between old and new, supported by a strong design and planning strategy.

We are unable to formally recommend builders due to our professional code of conduct. However, we can introduce you to contractors we have worked with over many years, who have delivered projects in line with our expectations. We can suggest suitable builders based on your project type, scale, and location.

Yes – we manage a structured tender process by issuing technical drawings and documentation to selected contractors, allowing you to compare quotations and make an informed decision.

We assess contractors based on their experience, quality of previous work, reliability, and the competitiveness of their pricing. This ensures a balanced decision between cost and quality.

Yes – we collaborate closely with structural engineers and other consultants to develop coordinated technical designs and ensure the project is buildable and compliant.

We coordinate all required consultants, including structural engineers, party wall surveyors, and other specialists, ensuring a cohesive and efficient design process.

Yes – we can act as contract administrators during construction, managing communication between client and contractor, reviewing progress, and helping resolve on-site queries.

Yes – we carry out regular site visits to monitor construction progress, review quality, and ensure the work aligns with the design and technical drawings.

We maintain design quality through detailed technical drawings, regular site inspections, and ongoing communication with the contractor to ensure the design intent is properly executed.

We address issues as they arise by reviewing the situation on site, coordinating with the contractor and consultants, and providing clear guidance to resolve them efficiently while maintaining project quality.

Yes – we support the final stages of the project, including inspections, resolving outstanding items, and assisting with building control sign-off to ensure the project is completed correctly.

We primarily work across London, with a strong focus on Central and South West London boroughs where we have extensive experience with local planning authorities.

Yes – while most of our work is based in London, we can take on projects in surrounding areas depending on the scope and requirements.

Yes – we offer both in-person and remote consultations via video calls, allowing us to discuss your project efficiently at the early stages.

Yes – site visits are typically included as part of our service, particularly during survey, and construction stages.

Yes – we have strong experience working with different London boroughs and understand how to navigate varying planning policies and requirements.

Yes – we work across a wide range of property types, including dense urban settings and larger suburban homes, adapting our approach to suit each context.

Yes – we can support projects across the UK, particularly at early design and planning stages, depending on project scale and logistics.

Yes – we regularly liaise with local councils and planning departments, which helps streamline the application process and respond effectively to feedback.

Yes – we can carry out an initial desk-based review of your property, including planning policies and constraints, before arranging a site visit where needed.