Extension plans and drawings across Penzance
For Penzance homeowners we handle extension plans and drawings, with fees agreed in writing before any work starts.
- Guide price in PenzanceFrom £1,200 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsTR18
Who this service is for
- Projects that need a planning application or other approval
- Homeowners at the very start of a project
- Anyone who wants fixed designs before getting build prices
Extensions in and around Penzance
Our survey diary covers Penzance, including TR18. We also work in nearby Camborne (12 miles), Redruth (16 miles), Falmouth (21 miles), Truro (24 miles).
Just over the Devon border, Plymouth is about 64 miles away. In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
Do I need planning permission in Penzance?
In England the main routes are permitted development (ideally confirmed with a lawful development certificate, £274), larger home extension prior approval (£249, 42 days) and a householder planning application (£548, normally 8 weeks), with council fees as set from 1 April 2026.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Fees in Penzance
Fees below are our Penzance guide (×1.02, the South West England factor), including VAT. Council and building control fees are extra.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,200 – £2,250 |
| Standard | Planning drawings plus building regulations drawings | £2,200 – £3,900 |
| Premium | Full pack with structural calculations and 3D visuals | £3,450 – £5,650 |
Want a range for your exact size? The guide-price tool takes about a minute.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Penzance, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does this take for a Penzance home?
2–6 weeks for drawings, depending on the council and the complexity of the project.
Who do I contract with in Penzance?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
How much do extension plans cost?
Our design packs range from about £1,200 to £5,650 including VAT, from planning drawings only to a full pack with building regulations drawings, structural calculations and 3D views. Council fees are separate.
Book a free site visit in Penzance
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.