Extension plans and drawings in Letchworth Garden City
We prepare extension plans and drawings for homes in Letchworth Garden City, as a stand-alone service or as the first stage of a design and build project.
- Guide price in Letchworth Garden CityFrom £1,250 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsSG6
Covering Letchworth Garden City
Our survey diary covers Letchworth Garden City, including SG6. The same team covers Hitchin (3 miles), Stevenage (5 miles), Welwyn Garden City (12 miles), Harpenden (13 miles), all within easy reach.
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
Included in a typical project
- 3D views to check the look and the light (full pack)
- Planning drawings: existing and proposed plans and elevations, site and location plans
- Two or three layout options to compare
- Measured survey of the house and garden
- Structural calculations from an engineer (full pack)
- Building regulations drawings and specification
Design and approval fees for Letchworth Garden City
Guide fees for Letchworth Garden City including VAT, using our East of England factor of ×1.06. Council and building control charges are not included.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,250 – £2,350 |
| Standard | Planning drawings plus building regulations drawings | £2,300 – £4,050 |
| Premium | Full pack with structural calculations and 3D visuals | £3,600 – £5,850 |
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in Letchworth Garden City?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
What happens next
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in Letchworth Garden City
How long does this take for a Letchworth Garden City home?
2–6 weeks for drawings, depending on the council and the complexity of the project.
Who do I contract with in Letchworth Garden City?
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.
Do you cover all of Letchworth Garden City?
Yes. We cover Letchworth Garden City and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
Do I need an architect?
Not necessarily. For most extensions an experienced designer or architectural technologist is enough. For listed buildings or complex sites an architect’s input can help.
Book a free site visit in Letchworth Garden City
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.