The Top 10 Pitfalls For Self-Builders


If you’re in the process of trying to work out how much of your project you want to, or can take on, we’ve compiled the top 10 pitfalls for self-builders to be aware of. You may find it useful to understand more about what’s involved at various stages, which professionals would normally undertake the work, and where self-builders are at greatest risk.

1.     Getting planning permission

Getting planning can be problematic on some sites and an architect should advise on the best way to approach it.

This can be as straight forward as preparing your design and submitting a full planning application. It can be as complicated as establishing some key principles through permitted development rights before a pre-planning process, outline planning and full planning application.

Employing an architect should help you minimise your financial risk as you establish the likelihood of getting planning permission for what you want.

2.    Architectural design up to getting your planning permission

This work would normally be carried out by a qualified architect if you want to make the most of what your site offers and want a bespoke design to suit you.

To complete the design and get planning approval the architect might call on specialists to provide information he needs. These are project and site dependent but will often include a topographical survey and a phase one ecological survey. He may also require things such as a heritage statement, visual impact assessment, arboricultural survey and contamination survey to name but a few. Nearly all this information must be carried out by an accredited person if the information is to be considered valid by the planning authority.

Without the necessary information, planning permission will be delayed because the planners won’t have all the information they need. If you haven’t considered the cost associated with getting all the necessary information your budget and financial plan will suffer.

3.    Construction information

To ensure a house is built to the required design and specification, to facilitate accurate costing and allow the build contract to be administered, a comprehensive construction pack must be prepared. This pack includes a small sub-set of information required to meet building regulations.

This work is normally undertaken by an architect and/or an architectural technician. He will work out how best to build the house and often call on other experts for detailed technical information. These might for example, include specialists in home automation, heating and electrical systems or renewable energy. Once complete the information will typically comprise 30 – 40 detailed drawings and a finishes schedule.

Without this information, the design can become diluted by the building contractors. Prices provided by contractors will be unreliable as gaps in information will be replaced by assumptions to suit the contractor. Administration of the contract will be difficult, potentially costlier and requests for additional money from the contractors during the construction, almost inevitable.

4.    Budgeting and cost planning

Budgeting and cost planning for a construction project is complex. Prices change over the duration of the design development, there are a myriad of interrelated components and there is no standard approach.

During the early stages of the design the architect should be considerate of the likely build cost of his proposed design. As the scheme develops a quantity surveyor or cost consultant will sometimes be engaged to further refine the estimated costs. Finally, a price will be put against the scheme either through a negotiated contract process with a nominated contractor or through a tendering process.

Without a robust approach to budgeting and cost planning the self-builder can find they have planning permission for something they can’t afford to build. It is quite possible this fact won’t emerge until all the architectural work is complete and significant cost incurred.

5.    Contracts

The construction contract would normally be prepared by an architect, project manager or contract administrator. The most commonly used type is a JCT (Joint Construction Tribunal) contract. To be robust it must be supported by a comprehensive set of information (the construction pack).

A poorly prepared contract, open to individual interpretation, is difficult to administer fairly and inevitably leads to adversarial relationships between the parties. In turn this results in budget and programme overrun with all the associated costs and angst.


6.    Getting the design you really want

You don’t want to move in to a completed house and start listing the things you wish you’d done differently otherwise you might as well have bought a house off the open market. Knowing your architect is doing a great job for you will mean being confident their listening to what you want and designing a house you’ll be able to afford to build.

7.    Staying within budget during design

Budget overrun is rightfully most people’s biggest fear. Bear in mind a professionally run construction project will involve a cost consultant or quantity surveyor. It’s worth considering the implications if your project were to overrun by 20%. We frequently see examples self-build overruns of 50% upwards.

You need to be confident at every stage, from when you apply for planning permission to when your house is completed, you’ll still be within budget. There are so many interrelated component parts to a house that cost analysis isn’t simple and with the significant costs of the substructure (below ground) and superstructure it is rarely a case of simply substituting one cost item with another.

8.    Staying within budget during construction

It’s only possible to keep within budget during the construction if you have a comprehensive set of documents, a full construction pack, on which prices have been fixed and contracts agreed. Without these the scope for misunderstanding is significant. A competent contract administrator will ensure the appropriate documents are in place and that they are adhered to by the contractors during construction.

Without a rigorous approach the self-builder can find themselves financially exposed by paying for work and materials not yet incorporated into the build. They are also likely to face claims for variations in cost from the contracts as misinterpretation of what has been priced for comes to light. These additional costs can quickly run to many tens of thousands of pounds.

9.    Programme overrun

This is perhaps the most commonly acknowledged risk of a self-build project. Whilst it is straight forward to get a main contractor to commit to a programme of work, this is almost impossible to achieve when using multiple sub-contractors. They will nearly all be dependent on other contractors on the project over whom they have no control.

The true cost of programme overrun is often overlooked with such things as the cost of alternative accommodation if you have sold your house to fund the build, additional interest on development loans before they can be converted in to a conventional mortgage and the extra cost of site attendances. Site attendances are those things shared across multiple trades such as plant and scaffolding as well as site welfare facilities which must be provided by law.

10.  Contractors going into administration or liquidation

The construction industry is peppered with contractors operating on a small scale, very good at their jobs but less able to manage their finances. Consequently, financial failure is common place.

During construction, the client should never pay for labour or materials that haven’t been incorporated in to the building. Part of the role of a contract administrator is to ensure this doesn’t happen.

In some circumstances, where bespoke products are manufactured off site, an advance payment may be required. In this case a vesting certificate should be issued by the contractor to ensure any goods at their site are clearly marked as the property of the client, thus protecting them from administrators should the business fail.

If you wanted to see what’s needed before actual construction, this post all about pre-construction packs may be useful to you.

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