Two-storey extension plans and drawings in Merseyside

Merseyside at a glance

Nation: England
Price region: North West England
Postcode areas: CH, L, PR, WA
Towns covered: 42 listed below, plus surrounding villages
Site visits: Free, no obligation

What a set of extension plans involves

This service suits you if you want clear, accurate plans for a two-storey extension, whether to apply for planning, check permitted development or get build prices. You get a measured survey, sketch options with guide costs, a chosen design developed into planning drawings and, if you go ahead, building regulations drawings coordinated with the structural engineer. Because we also build, the drawings are prepared with the build in mind.

Towns in Merseyside include Liverpool (L1), Birkenhead (CH41), St Helens (WA9), Southport (PR8), Wallasey (CH44) and Bootle (L22). If yours isn't listed, we still cover it.

Fees

Planning drawings (survey and design) are a guide of £2,000–£3,500 and building regulations drawings and specification £1,500–£4,000, with your design stage priced in writing before it starts.

Rules in England

In England, the plans support either a householder application, costing £548 (or £575 for applications made from 8 December 2026), or a lawful development certificate for permitted development, costing £274 (about £288 for applications from 8 December 2026). They must show the extension's relationship to the original house, the boundaries and neighbours, because two-storey rear permitted development depends on the 3 m and 7 m limits.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

The Party Wall etc. Act 1996 applies, so notices may be needed for work on or near a shared wall or boundary.

Getting the design right

Planning drawings versus building regulations drawings

Planning drawings show what the extension looks like and how it affects neighbours. Building regulations drawings show how it is built: foundations, structure, insulation, fire safety, ventilation and drainage. Most two-storey extensions need both, prepared at different stages.

Compare options early

Sketching two or three layouts, such as rear, side or part two-storey, is the cheapest point to make big decisions. Each option comes with a guide cost and a view on the approval route, so you choose with the full picture rather than discovering limits later.

How we work in Merseyside

Look at the house
We start in Merseyside with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Get it approved
Once you're happy with the design we submit it to the council for Merseyside and deal with any questions from the planning officer.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Towns we cover in Merseyside

Two-storey extension plans and drawings in Merseyside: questions

Can I use plans from a previous owner's planning permission?

Sometimes. If the permission is still valid, usually within three years of the decision in England, you can build to it. The drawings may still need updating for building regulations, and the design may not suit your needs. We check old plans and permissions at the free site visit.

Do I own the plans once they are drawn?

You receive copies of the drawings to use for your project, including your planning application and building regulations approval. Copyright in drawings normally stays with whoever prepares them unless agreed otherwise. Your written design stage price sets out how the drawings can be used.

How long do extension plans take to prepare?

Survey, design and planning drawings usually take 4 to 8 weeks, depending on how many options you want to explore. Technical design, structural calculations and building control approval take a further 4 to 8 weeks, and this can overlap with the planning decision period.

Neighbouring areas

All extension services in Merseyside · About two-storey extension plans and drawings