Building with Neighbours

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extension site before works3D sketch of proposed extensionkitchen design

Have you ever considered building with your neighbours as a collaborative project? Well, the weather has broken and today we started work on a pair of side return extensions between neighbours in Bath. If you want a sneak preview of the final result, you can see a photo at the foot of the page.

extension site before works

Neighbours and their extensions

More often than not, the news of a neighbour’s plan to build is met with concern and worry;  but in this case, both neighbours wanted side return extensions, seeing an opportunity to collaborate and reduce overall costs. They asked us to produce a design and after a few weeks of briefing, we agreed on the following initial schematic.  Each side had different internal requirements, and the existing buildings already had subtle differences in appearance.  However, we wanted to keep the two extended structures symmetrical, enhancing the look of the rear elevation of both properties.  Internally, the side return extensions would both provide for an open-plan kitchen diner, albeit with different configurations.

3D sketch of proposed extension

Pre-Application and Planning Approval

The pre-application identified that planning consent would be required because the height exceeded 3m within 2m of the boundary.  This, despite the fact that the neighbours were affecting each other equally. Permitted development rights didn’t apply.  We produced formal drawings and, after a few more weeks, the council approved the planning application.

It is important to go through the pre-application process;  it saves time and money in the long run. It makes good sense to work with sketch proposals without committing to the expense of drawings which may need to be changed.  Planning officers are generally helpful and will point out issues which eventually make it easier for the full application to pass.

Building Control

The Council approved the building control and structural engineer drawings;  work could then begin.  The building control officer provided a list of stages he wished to inspect as the project progressed;  these related mainly to drainage and structural elements, as well as a final electrical certificate.

Competitive Tenders and Pricing

In parallel, we also ran a competitive tender for delivery.  We defined the interior fit (heating, plumbing, electrics, lighting, flooring, kitchen, decoration, everything) both in drawings and written specification, allowing a meaningful price comparison to take place.  In this case, four of the six invited contractors tendered bids, of which one was successful for both properties.  At this time, contractors are very busy and often don’t tender for work;  so if you only invite three contractors, you may get just one return.

As a general comment on pricing, our pricing spreadsheets cover everything;  the construction elements (from the tenders), fixtures and fittings (provided by others), and professional fees.  Our clients then understand the predicted total cost of the project.  Clients may need a loan, or to re-mortgage, for a renovation of this size and the lender will want to know the total outlay;  it is preferable to make only one application to the bank.

kitchen-diner schematic


home renovation savings

Due to the collaborative nature of the project, the clients made financial savings in hard cash. BANES Council offered to reduce some of the fees because much of the design was similar, and they could make joint site visits. Architectural and structural engineer services were largely common, one home being a mirror-image of the other.  The glass structure supplier used economies of scale to pass on savings to our clients through single visits to fit both.  We reduced our design and project management services given the similarity and proximity of the projects. So the clients have indeed saved several thousands of pounds in this joint venture;  we estimate roughly 10% on materials and labour and 50% on project management;  so around £10 000.

side return extensions

Having let winter pass, and awaiting reasonable spring weather, work has now started on the side return extensions.  We’ll add to this blog over the coming months as the structures rise from the ground;  the next in the series will report on pumping concrete for the foundations.

Whilst we’d like you to follow this project through our series of blogs, if you want a sneak preview of the final result, here it is:

photo showing side return extensions after the project was finished

and one of the kitchens:


Property renovations in Bath

You may be considering a project of your own, or perhaps building with neighbours. Our company designs and manages everything for you from initial concepts through to delivery of the completely finished result. If you think we can help, we would invite you to read about our complete home renovation service.

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