ISA SpecEng
Architectural Design & Project Delivery
Concept design, planning applications and full architectural drawings for residential and commercial developments.
From Starting from £95/hr per project
Begin EnquiryOverview
ISA SpecEng's architecture and design service takes projects from initial concept through to planning approval and construction documentation, providing clients with a single, experienced team throughout. Whether you are extending a family home, developing a residential scheme, or fitting out a commercial premises, we apply the same rigour to every brief — translating your vision into drawings that are both buildable and approvable.
Our designers work across a wide range of typologies including HMO conversions, new-build residential, retail fit-outs, and mixed-use developments. We have an established working relationship with local planning authorities across London and the South East, and our knowledge of policy and permitted development rights helps clients navigate approvals efficiently and cost-effectively.
Every project is managed with clear communication from first meeting to final handover of documents. We provide 3D visualisations and detailed technical drawings so you can see — and sign off — the design before a single brick is laid.
Initial Consultation
We meet to understand your project goals, constraints, and budget. We explain what is feasible within planning policy and outline the design options available to you.
Concept Design
We develop initial sketches and spatial layouts that respond to your brief. These are presented with 3D visuals so you can review and refine the design before detailed work begins.
Planning Application
We prepare and submit all drawings, documents, and supporting statements required by the local planning authority. We manage the application and liaise with the LPA on your behalf throughout the determination period.
Technical Design
Once planning is granted, we produce the full set of construction drawings — including floor plans, elevations, sections, and specification notes — ready for tender and Building Regulations submission.
Handover & Support
We issue the full drawing package and remain available to answer contractor queries during the build. Any required amendments are handled promptly to keep your project on schedule.
End-to-End Service
From feasibility and concept through to construction documents — one team, one relationship, no handoffs between different consultants.
Planning Authority Knowledge
Established relationships with London and South East local planning authorities. We know what each LPA expects, reducing delays and improving approval outcomes.
Residential & Commercial
We work across both sectors — from single dwellings and HMO conversions to retail fit-outs and multi-unit developments — applying the same quality of design at every scale.
3D Visualisations Included
Every scheme includes rendered 3D visuals so you can fully understand and approve the design before it moves into technical drawing stage — no surprises on site.
Transparent Fixed Fees
Our design fees are agreed in writing before work starts. No open-ended hourly billing — you know the cost of each stage before you commit to it.
From
£95/hr per
Starting from project
£750
half-day
£1,400
full day
£1,200
Feasibility from
£4,500
Projects from
All fees exclusive of VAT · Scope confirmed in writing before work begins
Request a QuoteDo I need planning permission for my project?
It depends on the scope of work. Many smaller projects fall under permitted development rights and do not require a planning application. We will assess your project during the initial consultation and advise on the correct route.
How long does a planning application take?
Local planning authorities have a statutory target of 8 weeks for householder applications and 13 weeks for larger schemes. In practice, timescales vary by borough. We will give you a realistic timeline based on your specific LPA.
Can you help with Building Regulations as well as planning?
Yes. Once planning approval is secured, we can produce the full technical drawing package required for Building Regulations submission and contractor tendering.
What types of project do you take on?
We work on residential extensions, loft conversions, HMO conversions, new-build dwellings, retail and office fit-outs, and mixed-use developments. Get in touch to discuss whether your project falls within our scope.
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