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HOUSE EXTENSIONS

HOUSE EXTENSIONS WITH ACA

Do you need more space for your growing family? Perhaps your home is in need of a makeover? Well, Allan Corfield Architects can help. It’s easier and more cost effective than you may think to extend or convert your garage or attic into a more habitable space. Now might be just the right time to consider a house extension.
ACA have completed numerous house extensions, mainly in the Central belt of Scotland – from Fife to Perth & Kinross, and from Edinburgh to the Scottish Borders. With the Government’s Permitted Development rights, you may not need Full Planning Permission for a house extension – this route makes it less expensive and time-consuming than you may think!
Over the last 10 years ACA have tailored the required house extension service to help the average homeowner get the necessary approvals in place – as
House Extensions

House Extensions

well as assistance in appointing a trusted local contractor.

When ACA provide a Fee Proposal for a house extension, we will split the required services up into logical stages. These have a fixed cost and an advised timescale. The RIBA suggest that an average fee for this type of project would equate to between 9-12% of the overall Construction Cost.

At ACA, we believe our clients should know all of the main facts and costs before committing to a project, so we work on a fixed cost rather than a percentage – that way our fee isn’t determined by how expensive your build is!

Survey & Existing Drawings
Step 1

SURVEY & EXISTING DRAWINGS
Stage 1
Nitial Designs
Stage 2

INITIAL DESIGNS
Stage 2
Planning/certificate Of Lawfulness
Stage 3

PLANNING/CERTIFICATE OF LAWFULNESS
Stage 3
Building Warrant Application
Step 4

BUILDING WARRANT APPLICATION
Stage 4
On Site Supervision
Step 5

ON SITE SUPERVISION
Stage 5
STAGE 1 – SURVEY & EXISTING DRAWINGS


  • Complete a basic measured survey of your existing home
  • Draw-up your existing home in our 3D drawing package
  • Provide Plan, Section & Elevations of your current home and garden

Estimated time – 1 week to complete drawings

STAGE 1 – SURVEY & EXISTING DRAWINGS

STAGE 2 – INITIAL DESIGNS

  • Meet with you to prepare a Project Brief (completed at initial meeting)
  • Complete a Project Programme, estimating how long the project should take
  • Prepare 2 or 3 design options in our 3D drawing package
  • Prepare our BIMx model, so you can walk around your home on your PC, TV or iPad
  • Complete a final option for your approval

Estimated time – 2 weeks to complete drawings
Planning Submission
STAGE 3 – PLANNING OR CERTIFICATE OF LAWFULNESS APPLICATION

  • Add relevant Planning information to drawings
  • Complete computer visualisations to aid planning application process
  • Complete online planning application submission
  • Deal with any planning queries during the process

 

Estimated time – 2 weeks to complete drawings

Note – Full Planning Approval process will take a minimum of 8 weeks, Certificate of Lawfulness application (under permitted development) will take a minimum of 4 weeks.
Lawfulness Application
STAGE 4 – BUILDING WARRANT APPLICATION

  • Obtain Structural Engineer quotes for the design service
  • Upgrade Planning drawings and add relevant construction information to layouts
  • Prepare basic construction details
  • Prepare warrant specification
  • Complete U-value calculations
  • Liaise with Structural Engineer and add their design information onto the architectural drawings
  • Obtain local builders’ estimates for the works
  • Lodge the Building Warrant application via the online portal (4-6 week review period)
  • Deal with any warrant queries
  • Help appoint a trusted local builder for your project

Estimated time – 3/4 weeks to complete drawings

PRODUCTION INFORMATION

If required ACA can also assist with on-site supervision, and checking of the local contractor’s work. However, we would hope that the contractor chosen would not need any assistance during the house extension construction – due to the quality of the information provided and the suitability of the contractor.

STAGE 5 – ON SITE SUPERVISION

 
  • Regular site visits to check on work and provide any assistance to the contractor
  • Provide Completion Certificate visit and certification via the local Council
 

Estimated time – 1 visit per calendar month (dependant on requirements)

On Site Supervision
Additional Info
Pre-application Planning Enquiry
If your project is contentious or doesn’t comply with Permitted Development it may be worthwhile getting pre-application planning advice.
Some planning departments will discuss the proposals over the phone, but due to workload most of the Councils now require a formal application.
A Pre-Application enquiry is a cost effective route which will give you a formal response from the planning team.
The process usually takes 21 days and shouldn’t cost any more than £160.
Generic Fee Proposal –

To give you an indication of how the costs are made up on an average house extension project, we have based this example of a single storey sun room extension with internal alterations. Budget approx £70,000 ex VAT:

Stage 1: Stage 1: Existing Drawings £800 (ex VAT)
Stage 2: Initial Designs £1,500 (ex VAT)
Stage 3: Planning Application £800 (ex VAT)
Stage 4: Building Warrant £2,800 (ex VAT)
Stage 5: On site Supervision £250 per visit
Total fee Total fee £5,900 (ex VAT)

Note – Application costs and other consultant fees are excluded and paid direct by client.

 
Structural Engineer Services

You will need an Engineer on most house extension or conversion projects for the Building Warrant Stage. The engineer will access the existing home and ground condition, before designing the foundations and the super-structure for the house extension. They will also provide any calculations required in order to satisfy the building warrant application. AC Structures basic engineering costs for a typical single storey house extension should be approx. £2,200 (ex VAT).

FIND OUT HOW WE CAN HELP YOU