Advice from the experts

1. Plot problems

The moment you finally find that elusive plot can be one of the most exciting steps of the building process - but don’t fall in love with a lump of land until you’ve done your homework.

Quite often would-be self builders run into trouble as they’ve overlooked the essential requirements or made assumptions. Things to check include:

• Services - you will need to investigate both availability and cost of connecting to all the services you need, e.g. gas, sewage, electricity, water and broadband. Check thoroughly and don’t assume you can even if you can see a phone pole nearby, for example. If services are not already connected or unavailable, you’ll need to get connection quotes or investigate off-grid solutions.
  
  
• Planning permission - check with the local planning department that the plot has planning permission, whether it’s outline or full planning permission. It is strongly advised to never purchase a plot without planning permission in place.
  
  
• Soil survey - it’s essential to get a soil survey to understand the qualities of the ground and what type of foundations your home will need to be built on. If the ground requires complex engineering such as piled foundations, this will add to your budget significantly, so you need to know before you get too far into the design process.

2. Not making key decisions at the design stage

"The design stage is critical,” says Iacopo Sassi, Director of Square One Architects based in Hampton, South West London. “It's very important to take as many decisions as possible before you actually start building.”

This not only includes big decisions like layout and architecture, but also finer details like choosing windows, doors, and fixtures and fittings. Comprehensive lists for each area of the build will ensure nothing is overlooked. You'll be able to procure your materials in advance and your builder will have the specifications they need to get started, without having to make assumptions. The more details you can finalise before construction, the smoother and faster your build is likely to be.  You'll minimise the stress factor for you and your team, too.

3. Unrealistic timetable

Being in a hurry can lead to issues, says Jonathan Hetreed, Director of Hetreed Ross Architects from Bath. Firstly, you're more likely to be disappointed with the finished results as you've not had sufficient time to reflect on the design and how it meets your needs, or the quality may not meet your expectations. Secondly, even if you do make that speedy timetable happen, Jonathan says, “it will probably cost you a huge amount because suppliers will see you're in a hurry and are likely to put their prices up.”

4. Blowing the budget

Budget is the most common place that self builders run into issues, including:

• Starting with an inadequate budget - It’s a common issue for self-builders to underestimate the cost of their project, and/or overestimate how far their funds will stretch. You need to marry your vision and expectations for your build with the realities of your budget. “A tight budget is okay,” says Jonathan Hetreed, “But having a budget that’s simply too small means the project is just not achievable.”


• Not having a contingency - Anyone who’s watched an episode of a home building show will know that curveballs are a certainty in the building process. “We always advise clients to have a contingency budget as the building process is not utterly cast iron and certain from the word go,” says Jonathan Hetreed. “You dig up the ground and you find something in it. There are potentially things that can go wrong or cost more. Some kind of contingency is sensible.”

5. Changing your mind mid-project

Making changes once a build has started will cost you money and time. James Carvell of Carvell Associates in North East England says: “Once you've made a decision, keep that decision. The cost of changing your mind increases further down the line you go. Just say you want to change a flat roof to a pitch roof. This has zero cost implications at the start of the project. But later on when you have fifteen guys on site and they're all swinging hammers, the materials have been purchased and the roof is half-built, the cost implications will be big.”