The 20 Most Common Mistakes Made by Self-builders...And How to Avoid Them.

1. Paying Up Front

Number one in the disaster league – and almost guaranteed to lead to problems – is paying builders up front. If a builder does not trust you enough to start work without up-front cash, you probably should not trust them. Pay up front and you relinquish all control over your builders; you take away their main incentive to turn up and expose yourself to the risk of having to pay twice should anything go wrong. Do not pay in advance for labour or for materials.

Problems and disputes on site are not uncommon. Sometimes workmanship is not up to scratch and builders have to be asked to put things right; some may fail to turn up when they say they will; you may even have to fire your builders. None of this is too much of a problem if the work has not yet been paid for, as the funds that have been withheld can be used to pay someone else to put things right — although you must pay for the work that has been completed.

One exception to the rule is when a subcontractor has to install an expensive item such as a boiler and asks for the money, because they do not have an account or credit facilities. In this event the only way to reduce risk is to pay for the materials yourself and to get them in your own name. If you want to get the builder’s discount, use their name or, failing that, take them with you when you buy.

2. Going Over Budget

Everyone does it, and usually it is by choice – as you gradually upgrade the specification – and there is no problem. However, occasionally, when there is absolutely no leeway in the budget, an overspend can spell disaster and even force a project to be abandoned.

To avoid running out of money, it is vital to leave a contingency sum in the budget, even if this is only a way of borrowing more money from somewhere, should it be needed. Preparing a detailed budget is essential, including a prediction of your cash flow requirement — the money needed to keep work going in between the release of loan funds.

Budget problems arise when the self-builder or a contractor underestimates costs, either through ignorance or naïvety. With the exception of groundworks (foundations), building costs are largely predictable. Look at other people’s build costs and those published every month in the H&R Beginner’s Guide and do not expect to build for any less.

3. Dismissing Difficult Plots

When first looking for a building plot, most people have a vision of a mature, level garden site with trees, hedges and grass, or perhaps a field, with nice straight boundaries, just waiting for a house to be dropped in. In reality, most building plots are messy, overgrown scraps of land, often with old buildings on them, rubbish, broken fences, odd and uneven boundaries and slopes. Novice self-builders often reject these ‘awkward’ sites because they look difficult to develop, but this can be a huge mistake.

Often the most difficult sites result in the most exciting and interesting new houses. You need to be able to see through the superficial problems and picture the plot’s real potential. Once cleared and levelled, a site can look far larger and far more appealing than it does at first sight, and almost any slope or ground condition can be overcome — at a price. The trick is to only consider the things that you cannot change, like the location, the neighbouring properties, and the views.

4. Making False Economies

If a job is worth doing, it is worth doing well. Cutting corners may help to reduce your build costs but it can also reduce the value of the finished property. If budget does become an issue and savings have to be made, the emphasis should be on getting the fundamentals right and saving on superficial cosmetic finishes that can be upgraded later. Alternatively, consider tackling the project in stages. A garage, attic conversion or an en suite bathroom are all projects that can be left until later when funds allow, yet will not prevent you from moving in.

A classic mistake is to cut the quality of building materials such as bricks, roof tiles and windows, instead of fixtures and fittings that can easily be upgraded later — building a quality structure should always take priority. Another common error is to try and save money on labour costs. Poor quality workmanship can lead to compromises, additional costs and delays later on down the line for the trades that follow, and poor-quality finishes will devalue the property.

5. Having More Than One Set of Plans on Site

Anyone who claims that the plans for their new home did not go through several stages of evolution is either a genius or a liar! It is almost impossible to get everything right first time and so changes or ‘improvements’ are inevitable, resulting in several generations of plans. The problem is that it is very difficult to keep everyone’s plans up to date, from the planning drawings, to the building regulations drawings and the engineer’s drawings, the drawings sent out to builders and suppliers, to the master set of plans on which all of your changes are made. The result is that everyone who has a set of plans can end up working to different dimensions — and different sets of mistakes because every plan has some errors on it! This invariably leads to confusion on site, resulting in mistakes that ultimately cost time and money. The only solution is to get lots of copies of each generation of drawings, and to religiously swap them for the old sets which must then be destroyed. Unless you do so, trying to pin down the blame for mistakes on site is a total waste of time!

6. Choosing the Cheapest 'Fixed' Quote

Everyone recommends getting at least three quotes for building work. This can be a good way to get builders to be competitive and to trim their profit margin, but if one price comes in significantly below all of the others, it is probably best to discount it altogether, no matter how tempting.

Typically the builder with the unbelievably cheap quote will have missed out key costs in their pricing, all of which will have to be added back in later, by which time the budget may be all but spent. At the end of the day, someone has to pay for the building work and it is not going to be the builder.

If you take the cheap quote, the shortfall usually won’t reveal itself until near the end of the project, at which stage the builder will start to vanish for long periods as they try to make up money on other jobs, and/or start to make seemingly unreasonable demands for more money for ‘extras’, or for money up front as their cash flow breaks down.

If you refuse to pay or threaten to sue, the builder may simply vanish altogether. By this stage your choice is to understand that the problem is partly of your own making and to pay up, or else face having to pay someone else to complete the project — an option which usually proves more expensive. A contract is rarely worth anything in this situation, other than as a device to force bankruptcy.

7. Not Having Site Insurance/Warranty

Building sites are dangerous places. They are also insecure and therefore vulnerable to theft and vandalism. Failing to take out adequate site risks insurance can prove an expensive mistake if something valuable is taken from site, or if the site is vandalised or damaged by the elements.

The only way to protect your investment from the various risks is to take out specialist site risks insurance. Your contractor may carry this, but make sure they have adequate cover and that it is up to date. Insurers often recommend you have your own cover anyway, as you are ultimately responsible for what happens on your site. If you are project managing, having your own policy is essential. A single policy, costing around 1% of the build budget, can combine site insurance for tools and materials, insurance for building works in progress and public and employer’s liability cover. You can also insure caravans, plant and machinery and add a short-term bond to cover works when constructing a highways access (in areas where the local authority will allow this).

It is also a good idea to take out Latent Structural Defects Insurance, otherwise known as a ‘warranty’. Trying to sell a house without a build guarantee can be difficult.

8. Not Checking Plans

You may provide your builders with a set of plans to price from, and your plans may have been inspected by countless planners and building control surveyors, but invariably there will be errors that no one will spot until work has started on site and two walls don’t line up, a staircase does not fit, or a window is missing because it is on the elevations but not the floorplans. The designer is probably to blame – it is human error – but check out the disclaimers in their contract or on their plans and you will quickly realise that they are not culpable. They may apologise, but are unlikely to be willing to pay for remedial work.

The only solution is to check and doublecheck all of the measurements yourself and to try to imagine the plans in three dimensions. A great way to do this is to build a model, or to use a computer-assisted design package into which you feed dimensions for the computer to generate a three-dimensional model. On a computer, any discrepancies in the measurements will soon show up, and in three dimensions you may spot all sorts of design issues that you may never have previously considered.

9. Wasting VAT

All of the labour and most of the materials involved in building a new home are zero rated for VAT but you can only benefit from this saving on materials by using a VAT registered builder who will zero rate their supply, or by buying everything yourself and making a claim under Customs and Excise Notice 719. To do this you need to keep good records, including receipts for everything that you buy, with your name on it and the site address. Many people fail to get back as much VAT as they should because they do not keep records or do not know what they can claim.

The best way to maximise VAT savings is to read the rules and take advantage of them. Subject to details, some of the less obvious areas on which it is possible to reclaim VAT include kitchen ranges, outbuildings, turf, trees and other planting, fitted bedroom furniture, part of scaffold costs and even design fees, you just need to know how.

There are also VAT concessions on approved alterations to listed buildings, conversions, renovation work to homes that have been empty for at least three years or where there is a change in the number of dwelling units, and also on some energy efficient materials.

10. Underestimating the Role of Project Manager

Acting as your own building contractor can potentially lead to a saving of 10-15% compared to using a builder, but only if the job is done well. Mismanaging a project can reduce this cost saving considerably and in some instances can end up adding to costs. Even when handled well, it will usually take longer to build using subcontractors employed directly compared to using a professional contractor. A contractor has experience and access to a network of reliable subcontractors who will do their best not to let them down in terms of scheduling.

The job of project manager is time consuming and highly involved. It requires an understanding of the building process, good people skills, strong negotiating skills, leadership, the ability to forward plan and predict the critical path to keep work progressing and avoid delays, plus the ability to manage and control money. It is also essential to be able to visit the site at least once a day and to be on the end of a telephone whenever there are problems — which there always are!

11. Taking on Too Much DIY

We have all read stories of self-builders who have built for next to nothing by doing all or most of the building work themselves on a DIY basis, and for many people this seems like a great way to reduce costs and get more home for their money. DIY self-build is fine in principle, but in reality it is often massively over-ambitious and can lead to delays, cost overruns and can put huge pressure on health and relationships. What many DIY self-builders fail to point out is that they are at least semi-skilled builders, and have lots of free time available, either because they are retired or semi-retired, have an independent income or a job that gives them lots of time off.

Only take on as much DIY work as you have time to complete and choose tasks for which you have the skills and which will not hold up and delay the other trades if you do not complete them on time. The simplest tasks are decorating, second fix plumbing and electrics (you can still do both despite the new regulations) and landscaping.

12. Having More Than One Point of Contact on the Site

The key to a successful relationship with a builder is often down to good communication and understanding of the dynamics of the relationship. There is a temptation to turn up on site and discuss any problems or decisions that need making, with whoever is around at the time, but this can lead to all sorts of mistakes and misunderstandings that can cost money and cause delays — never mind holding up work unnecessarily. If you are using a contractor, communicate directly with them or their appointed site foreman. When it comes to negotiating the cost of any variations to a fixed price contract, known as ‘extras’ always deal direct with the contractor. If you are project managing the build yourself, you should have a single point of contact with each team of subcontractors. It will also be useful to have a single subcontractor on site who takes on the role of site foreman, taking control of things in your absence, managing deliveries etc. As carpenters tend to come on site at every stage of the project, it is often a carpenter who takes on this role.

13. Leaving Key Decisions Until Too Late

Plumbing fittings with hot and cold pipes and waste pipes showing because they are in the wrong place; furniture that does not fit; doors that open the wrong way; radiators in the way of furniture; cables trailing across floors to lamps or speakers; uneven floors at door thresholds — all are symptoms of having left key decisions until the last minute instead of planning ahead. If you want a neat finish that looks uncluttered, it requires a great deal of forethought to resolve all of the little design issues that have a huge impact on the finished result. Before you start first fix, you need to have designed your lighting scheme, chosen your floor finishes, designed your bathrooms and kitchen and planned the position of all of your key items of furniture; otherwise floor levels will vary and doors will have to be removed and re-hung — all delaying completion and adding to costs.

14. Leaving Builders to Make Decisions

If left to make a decision about something, builders will usually – although not always – do what is easiest for them. It is not just builders — it is human nature! Some builders are incredibly talented and can think ahead and head off problems to make sure that the building works, that floors and ceilings are level, that services are in the right place and concealed, but never bank on it.

15. Wasting Materials

Buying materials direct can mean making big savings, as it avoids the mark-up made by the contractor and puts you in direct touch with suppliers to negotiate discounts. This will prove a false economy, however, if you get your quantities or sizes wrong and end up either with too many materials or the wrong items. Some suppliers will take items back, but by the time you have paid for haulage and a restocking charge of around 10-15%, there may be nothing left to refund!

Get your suppliers to check quantities for you, especially for bricks and roof tiles, and ask your builders to double check for you. For a larger project it might be worth getting some estimating software or paying a quantity surveyor. A builders’ merchant can also produce a basic bill of quantities.

16. Under-investing in Design

Design Quality: A well-designed house need cost no more to build than a very ordinary, or even a badly designed house, but will be worth considerably more. Many self-builders feel that they can design a house themselves and only engage the services of a professional designer to produce planning drawings. Whilst this route can work and can help to keep design fees down, it can also be a missed opportunity that ends up costing money through reduced end value. Failing to invest in design, just a few percent of the total cost, can prove a false economy.

Design Detail: Every hour spent planning a building project is two hours saved on site. One sure way to help keep a project running smoothly is to invest in detailed design drawings that the builders can easily follow and which resolve the key design issues well in advance. Failure to invest in the additional cost of good drawings can lead to delays on site whilst the designer comes out to meet the builder — all of which will cost in the end!

17. Not Discussing Budget

It is remarkable how many people end up with a set of plans for exactly the house they want, only to discover once they get in quotes from builders that they cannot possibly afford the build costs. This happens either because of a failure to discuss their available build budget with their designer, or because the designer completely ignored the budget or has no real understanding of current build costs.

The solution is to be up front about your available funds and to do your own research on likely build costs by studying the Build Cost Tables in the back of H&R.

18. Ignoring Planning Conditions

Every planning permission will have a schedule of conditions, some of which must be formally discharged in writing before work can commence. Failure to discharge these conditions before starting work means that the development itself is not legal and whilst they can sometimes be dealt with retrospectively if there is a genuine oversight, it can occasionally be very serious, it could even result in prosecution and the property being demolished at your expense. Typical conditions require the approval of key materials such as roof tiles and bricks and approval of landscaping and planting schemes, sometimes if it is a complex development they could involve archaeological or flood compensation works etc. It is possible to appeal against a condition if you feel it is unreasonable, but only before work has started. If you win then it may be reworded or removed from the consent, but this can take many months and there is no guarantee of success. If you have a difficulty complying with a condition, before starting work on site talk to the planners about making another application to remove or vary its terms.

19. Forgetting to Notify Neighbours

Neighbours can get very nasty when it comes to building projects. They can oppose your planning applications and can make you observe the letter of the law when it comes to working hours and site practice. To avoid problems, make sure you respect boundaries, keep site noise down and, above all else, comply with the Party Wall Act if you are building anywhere within 6m of the boundary — visit www.odpm.gov.uk for details. Providing you stick to the law, the neighbours cannot prevent you from building your home.

20. Failing to Order Materials on Time

Not all building materials are available on an ‘on demand’ basis and so it is essential to plan ahead to make sure that materials that need ordering in advance are available as and when needed to keep building work progressing. Failure to do this can result in delays. With hire charges on scaffold and mixers, interest on finance, rent and storage costs, every extra week on site costs money. A more serious consequence of delays to the build schedule can be the risk of losing key tradesment to other jobs.