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  • Writer's pictureAdil Bashir (Baz)

Guide to extensions and loft conversions

We've designed and gained planning permission for hundreds of home extension and loft conversion projects and wanted to share with you some important points and considerations.

Where to begin

The best and most obvious step is to contact a design professional who can give you a quick and valuable explanation of technical, planning and cost implications. This often requires a site visit which can be free or sometimes a small fee is charged which is well worth the cost.

Planning permission; Householder and permitted

Is planning permission required? this is one of the first questions asked. Many extensions can be built under permitted development. For example a single storey extension of 3m and 4m is permitted for attached and detached home extensions respectively. Rear roof dormers are also permitted.

However there are restrictions for example depending on whether the property has been previously extended and also on the height of the proposed extension (3m eaves and 4m ridge max heights respectively).

If planning permission is required then this can take up to 10 weeks for a decision.

However a single storey extension up to 8m can be applied for under a type of permitted development application known as prior notification. This application takes just 4 weeks for a decision however neighbours are consulted and factors such as flood risk are also considered by the local planning authority.

The design process

The design brief meeting. Here we discuss in a lot of detail client requirements and the various design options that are available. Cost and budget is also confirmed to make sure any designs are suitable. Following on from the design brief, preliminary / sketch drawings including floor plans, elevations and sections are produced. These drawings should clearly show the proposals and their relationship with the existing buildings and space.

Once preliminary design is agreed we will then proceed (if necessary ) with planning permission drawings including site plans, location plans. You may have another planning agent to submit the planning application or request us to also carry out this service.

For more on the Planning process see this link;

Detailed drawings and building regulations

For simpler projects, detailed drawings are not required however they are always recommended. Detailed drawings give you the confidence that any contractor bidding on the project is fully aware of the specification requirements. They also include detail such as structural design, window / door sizes, fire escape details, insulation requirements and electrical / lighting layouts.

You may decide to instruct detailed drawings whilst planning permission is being decided so that you have all the required details ready for the decision. A building regulations application must be submitted 2 weeks prior to commencement of works. There are two options; building notice and full plans.

A building notice application does not require any detailed drawings. A full plans application is where detailed drawings are approved by the building regulations inspector prior to any work starting on site. This type of application can take up to 6 weeks for approval but it gives the confidence that as long as the plans are followed, then the building will be compliant.

We often also submit the building regulations application on our clients behalf.

Final thoughts

Above all, make sure you receive advice and that you plan as much detail as possible to prevent unforeseen circumstances at construction stage which could end up costing £thousands extra.

Of course, we would love to hear about your project so feel free to get in touch. Click here to contact us and let us know when is a good time to arrange a call.

01332 977487

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