Spatial planning
Reading the site, the policy and the constraints together — then shaping a development strategy that planning officers can say yes to.
Planning & design · Cardiff · across Wales
Permission is the hard part. We're the keystone that carries it.
A Cardiff-based planning and design consultancy. We guide homeowners and developers through the Welsh planning system — from first feasibility to drawings, application and decision — and stay with the scheme until the answer lands.
Every Welsh local planning authority
Policy-led Planning Policy Wales & your LDP
Planning first, design second
What we do
Four ways we move a project from idea to approval.
Pure planning and design consultancy — no property sourcing, no deal-making. Just the work that gets schemes consented.
CAD layout & design
Floor plans, elevations and layouts that work for how you'll live or build — and read clearly against the design expectations in your area.
Planning applications
Householder and full applications prepared, submitted and managed through your authority — drawings, statements and the case for consent.
Development feasibility
Before you commit, an honest appraisal of what policy will allow on a site — so you spend on the schemes worth pursuing.
How it works
From your idea to permission granted.
One clear path. Every project runs the same honest sequence — and you always know which stage you're in.
01
Feasibility
We test your idea against Planning Policy Wales and your council's Local Development Plan — and tell you straight what's realistic.
02
Design
We draw the scheme: layouts, elevations and the supporting story that addresses the policy and the site.
03
Application
We prepare the full submission and lodge it with your local planning authority, handling the documents and the detail.
04
Decision
We manage the application through to determination — responding to the case officer and keeping it moving.
Your idea Permission granted
Who we are
Local knowledge, kept deliberately focused.
Keystone Southgate is run on the ground in Cardiff, working with clients across Wales.
We believe good planning advice is independent advice. That's why we stay in our lane — spatial planning, design and applications — and bring genuine care to schemes of every size, whether it's a single-storey extension or a multi-unit site.
We don't source property, find deals or broker purchases. Keeping our scope to planning and design means our advice is always on your side — and only your side.
Thinking about an extension, a conversion or a development site?
Tell us what you have in mind. We'll come back with an honest first view of what the Welsh planning system will allow — and how we'd get you there.