House Extensions

A house extension in the Glasgow area can have costs starting at £40,000, up to £120,000 or higher. This is all dependent on the extension size and level of quality and finishing.

Yes, you will likely need planning permission and/or a building warrant to build a house extension in Glasgow, depending on the specifics of your project.

1. Planning Permission

• You may not need planning permission if your extension falls under Permitted Development Rights. This typically includes:
  • Single-storey extensions that don’t extend beyond 3m (terraced house) or 4m (detached/semi-detached house) from the original house.
  • The extension does not cover more than 50% of the total garden area.
  • The height does not exceed 4m (or 3m if within 2m of a boundary).
  • It is not forward of the principal elevation (front of the house).
• You will need planning permission if:
  • Your property is in a conservation area or is a listed building.
  • The extension exceeds the size and height limits above.
  • The materials are significantly different from the existing house.

2. Building Warrant

Regardless of planning permission, you must obtain a building warrant from your local Council before starting work. This ensures compliance with Scottish Building Regulations related to structure, insulation, fire safety, and drainage.

A quotation from architectural practices with overheads can be in the region of £5-10k. We are considerably cheaper. Most will offer a excellent service, but their fees are often between 10-15% of the estimated build cost. At the other end of the spectrum, some companies offer a budget service for around £500, however drawings can often be of poor quality and will have insufficient information for your builder (DONT TAKE THE RISK!). Many are often unqualified and uninsured. The Home Architect is a registered practice with ARB (Architects Registration Board) and therefore has a high standard and code of conduct to maintain. We also carry full professional indemnity insurance appropriate to the size of projects we procure. You can get an instant quotation with our Architect Cost Calculator.

At The Home Architect we COMBINE our fees SO THAT YOU DONT HAVE TO WORRY ABOUT THE END FIGURE. We ensure our clients are aware of the costs involved in advance of committing to the work and the submission of applications.

Clients often confuse planning permission and a building warrant or think they are the same thing. Unfortunately, this is not the case and the two are entirely separate. Some projects only require one while others require both. We will advise you which permissions you need to have in place before you commence your building project. A planning application gives opportunity for proposed development to be considered in the context of its local setting. Some things that the Planning department will consider include if your development overlooks or overshadows neighbouring property as well as proposed colour and materials of finishes. Some small alterations can be carried out without the need for planning permission and this is known as Permitted Development. We can advise you if your proposals will require permission or not. A building warrant is normally required if you intend to erect, alter, extend, demolish or change the use of any structure. Building Standards concerns all aspects of the structure both internally and externally. They check for compliance with the Building Regulations to ensure public health and safety, conservation of fuel and power and that facilities are provided for those with disabilities.

If your project includes structural alterations, you will require the services of a Structural Engineer. We will advise you if this is the case. We keep their fees separate and we seek for them to quote and invoice directly. As stated previously we work with Structural Engineers on a regular basis and can recommend their services for you.

All our drawings are produced for the purposes of obtaining a ‘building warrant’. Therefore, the same drawing package will be sufficient for your builder to accurately price and build from.

Planning applications can take up to eight weeks to be decided. This is because of statutory legislation. Your application will be placed in their queue system and during this time we cannot influence its progress and it is out with our control. Building Control usually take around a month to two months to respond although this can vary from council to council. Typically, they tend to be slightly quicker. All of this is worth bearing in mind when anticipating start dates for your project.

Planning applications can take up to eight weeks to be decided. This is because of statutory legislation. Your application will be placed in their queue system and during this time we cannot influence its progress and it is out with our control. Building Control usually take around a month to two months to respond although this can vary from council to council. Typically, they tend to be slightly quicker. All of this is worth bearing in mind when anticipating start dates for your project.

The Home Architect is based south of Glasgow, in East Kilbride. We cover the whole of West & Central Scotland, which means Glasgow, West End, South Side, East End, Clydebank, Dumbarton, Bearsden, Milngavie, Kirkintilloch, Lenzie, Stepps, Cumbernauld, Hamilton, Motherwell, Bothwell, Uddingston, Cambuslang, Bellshill, Newton Mearns, Paisley, Bridge of Weir, Houston, Bishopton, Renfrew, Livingston, Stirling, Falkirk and more.